| 1 | !> @file lpm_advec.f90 |
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| 2 | !------------------------------------------------------------------------------! |
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| 3 | ! This file is part of the PALM model system. |
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| 4 | ! |
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| 5 | ! PALM is free software: you can redistribute it and/or modify it under the |
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| 6 | ! terms of the GNU General Public License as published by the Free Software |
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| 7 | ! Foundation, either version 3 of the License, or (at your option) any later |
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| 8 | ! version. |
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| 9 | ! |
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| 10 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY |
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| 11 | ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
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| 12 | ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
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| 13 | ! |
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| 14 | ! You should have received a copy of the GNU General Public License along with |
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| 15 | ! PALM. If not, see <http://www.gnu.org/licenses/>. |
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| 16 | ! |
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| 17 | ! Copyright 1997-2018 Leibniz Universitaet Hannover |
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| 18 | !------------------------------------------------------------------------------! |
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| 19 | ! |
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| 20 | ! Current revisions: |
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| 21 | ! ------------------ |
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| 22 | ! |
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| 23 | ! |
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| 24 | ! Former revisions: |
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| 25 | ! ----------------- |
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| 26 | ! $Id: lpm_advec.f90 3562 2018-11-23 12:06:35Z forkel $ |
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| 27 | ! variables documented |
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| 28 | ! |
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| 29 | ! 3274 2018-09-24 15:42:55Z knoop |
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| 30 | ! Modularization of all bulk cloud physics code components |
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| 31 | ! |
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| 32 | ! 3241 2018-09-12 15:02:00Z raasch |
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| 33 | ! unused variables removed |
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| 34 | ! |
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| 35 | ! 3207 2018-08-27 12:55:33Z schwenkel |
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| 36 | ! Minor bugfix for sgs-velocities in case of cloud droplets |
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| 37 | ! |
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| 38 | ! 3189 2018-08-06 13:18:55Z raasch |
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| 39 | ! Bugfix: Index of the array dzw has to be k+1 during the interpolation. |
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| 40 | ! Otherwise k=0 causes an abortion because dzw is allocated from 1 to nzt+1 |
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| 41 | ! |
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| 42 | ! 3065 2018-06-12 07:03:02Z Giersch |
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| 43 | ! dz values were replaced by dzw or dz(1) to allow for right vertical stretching |
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| 44 | ! |
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| 45 | ! 2969 2018-04-13 11:55:09Z thiele |
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| 46 | ! Bugfix in Interpolation indices. |
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| 47 | ! |
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| 48 | ! 2886 2018-03-14 11:51:53Z thiele |
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| 49 | ! Bugfix in passive particle SGS Model: |
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| 50 | ! Sometimes the added SGS velocities would lead to a violation of the CFL |
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| 51 | ! criterion for single particles. For this a check was added after the |
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| 52 | ! calculation of SGS velocities. |
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| 53 | ! |
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| 54 | ! 2718 2018-01-02 08:49:38Z maronga |
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| 55 | ! Corrected "Former revisions" section |
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| 56 | ! |
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| 57 | ! 2701 2017-12-15 15:40:50Z suehring |
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| 58 | ! Changes from last commit documented |
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| 59 | ! |
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| 60 | ! 2698 2017-12-14 18:46:24Z suehring |
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| 61 | ! Particle interpolations at walls in case of SGS velocities revised and not |
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| 62 | ! required parts are removed. (responsible Philipp Thiele) |
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| 63 | ! Bugfix in get_topography_top_index |
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| 64 | ! |
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| 65 | ! 2696 2017-12-14 17:12:51Z kanani |
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| 66 | ! Change in file header (GPL part) |
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| 67 | ! |
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| 68 | ! 2630 2017-11-20 12:58:20Z schwenkel |
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| 69 | ! Removed indices ilog and jlog which are no longer needed since particle box |
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| 70 | ! locations are identical to scalar boxes and topography. |
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| 71 | ! |
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| 72 | ! 2628 2017-11-20 12:40:38Z raasch |
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| 73 | ! bugfix in logarithmic interpolation of v-component (usws was used by mistake) |
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| 74 | ! |
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| 75 | ! 2606 2017-11-10 10:36:31Z schwenkel |
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| 76 | ! Changed particle box locations: center of particle box now coincides |
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| 77 | ! with scalar grid point of same index. |
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| 78 | ! Renamed module and subroutines: lpm_pack_arrays_mod -> lpm_pack_and_sort_mod |
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| 79 | ! lpm_pack_all_arrays -> lpm_sort_in_subboxes, lpm_pack_arrays -> lpm_pack |
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| 80 | ! lpm_sort -> lpm_sort_timeloop_done |
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| 81 | ! |
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| 82 | ! 2417 2017-09-06 15:22:27Z suehring |
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| 83 | ! Particle loops adapted for sub-box structure, i.e. for each sub-box the |
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| 84 | ! particle loop runs from start_index up to end_index instead from 1 to |
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| 85 | ! number_of_particles. This way, it is possible to skip unnecessary |
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| 86 | ! computations for particles that already completed the LES timestep. |
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| 87 | ! |
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| 88 | ! 2318 2017-07-20 17:27:44Z suehring |
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| 89 | ! Get topography top index via Function call |
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| 90 | ! |
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| 91 | ! 2317 2017-07-20 17:27:19Z suehring |
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| 92 | ! |
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| 93 | ! 2232 2017-05-30 17:47:52Z suehring |
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| 94 | ! Adjustments to new topography and surface concept |
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| 95 | ! |
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| 96 | ! 2100 2017-01-05 16:40:16Z suehring |
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| 97 | ! Prevent extremely large SGS-velocities in regions where TKE is zero, e.g. |
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| 98 | ! at the begin of simulations and/or in non-turbulent regions. |
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| 99 | ! |
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| 100 | ! 2000 2016-08-20 18:09:15Z knoop |
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| 101 | ! Forced header and separation lines into 80 columns |
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| 102 | ! |
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| 103 | ! 1936 2016-06-13 13:37:44Z suehring |
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| 104 | ! Formatting adjustments |
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| 105 | ! |
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| 106 | ! 1929 2016-06-09 16:25:25Z suehring |
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| 107 | ! Put stochastic equation in an extra subroutine. |
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| 108 | ! Set flag for stochastic equation to communicate whether a particle is near |
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| 109 | ! topography. This case, memory and drift term are disabled in the Weil equation. |
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| 110 | ! |
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| 111 | ! Enable vertical logarithmic interpolation also above topography. This case, |
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| 112 | ! set a lower limit for the friction velocity, as it can become very small |
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| 113 | ! in narrow street canyons, leading to too large particle speeds. |
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| 114 | ! |
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| 115 | ! 1888 2016-04-21 12:20:49Z suehring |
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| 116 | ! Bugfix concerning logarithmic interpolation of particle speed |
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| 117 | ! |
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| 118 | ! 1822 2016-04-07 07:49:42Z hoffmann |
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| 119 | ! Random velocity fluctuations for particles added. Terminal fall velocity |
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| 120 | ! for droplets is calculated from a parameterization (which is better than |
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| 121 | ! the previous, physically correct calculation, which demands a very short |
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| 122 | ! time step that is not used in the model). |
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| 123 | ! |
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| 124 | ! Unused variables deleted. |
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| 125 | ! |
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| 126 | ! 1691 2015-10-26 16:17:44Z maronga |
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| 127 | ! Renamed prandtl_layer to constant_flux_layer. |
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| 128 | ! |
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| 129 | ! 1685 2015-10-08 07:32:13Z raasch |
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| 130 | ! TKE check for negative values (so far, only zero value was checked) |
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| 131 | ! offset_ocean_nzt_m1 removed |
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| 132 | ! |
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| 133 | ! 1682 2015-10-07 23:56:08Z knoop |
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| 134 | ! Code annotations made doxygen readable |
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| 135 | ! |
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| 136 | ! 1583 2015-04-15 12:16:27Z suehring |
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| 137 | ! Bugfix: particle advection within Prandtl-layer in case of Galilei |
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| 138 | ! transformation. |
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| 139 | ! |
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| 140 | ! 1369 2014-04-24 05:57:38Z raasch |
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| 141 | ! usage of module interfaces removed |
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| 142 | ! |
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| 143 | ! 1359 2014-04-11 17:15:14Z hoffmann |
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| 144 | ! New particle structure integrated. |
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| 145 | ! Kind definition added to all floating point numbers. |
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| 146 | ! |
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| 147 | ! 1322 2014-03-20 16:38:49Z raasch |
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| 148 | ! REAL constants defined as wp_kind |
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| 149 | ! |
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| 150 | ! 1320 2014-03-20 08:40:49Z raasch |
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| 151 | ! ONLY-attribute added to USE-statements, |
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| 152 | ! kind-parameters added to all INTEGER and REAL declaration statements, |
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| 153 | ! kinds are defined in new module kinds, |
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| 154 | ! revision history before 2012 removed, |
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| 155 | ! comment fields (!:) to be used for variable explanations added to |
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| 156 | ! all variable declaration statements |
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| 157 | ! |
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| 158 | ! 1314 2014-03-14 18:25:17Z suehring |
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| 159 | ! Vertical logarithmic interpolation of horizontal particle speed for particles |
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| 160 | ! between roughness height and first vertical grid level. |
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| 161 | ! |
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| 162 | ! 1036 2012-10-22 13:43:42Z raasch |
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| 163 | ! code put under GPL (PALM 3.9) |
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| 164 | ! |
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| 165 | ! 849 2012-03-15 10:35:09Z raasch |
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| 166 | ! initial revision (former part of advec_particles) |
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| 167 | ! |
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| 168 | ! |
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| 169 | ! Description: |
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| 170 | ! ------------ |
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| 171 | !> Calculation of new particle positions due to advection using a simple Euler |
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| 172 | !> scheme. Particles may feel inertia effects. SGS transport can be included |
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| 173 | !> using the stochastic model of Weil et al. (2004, JAS, 61, 2877-2887). |
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| 174 | !------------------------------------------------------------------------------! |
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| 175 | SUBROUTINE lpm_advec (ip,jp,kp) |
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| 176 | |
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| 177 | |
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| 178 | USE arrays_3d, & |
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| 179 | ONLY: de_dx, de_dy, de_dz, diss, dzw, e, km, u, v, w, zu, zw |
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| 180 | |
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| 181 | USE basic_constants_and_equations_mod, & |
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| 182 | ONLY: g, kappa |
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| 183 | |
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| 184 | USE cpulog |
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| 185 | |
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| 186 | USE pegrid |
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| 187 | |
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| 188 | USE control_parameters, & |
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| 189 | ONLY: cloud_droplets, constant_flux_layer, dt_3d, dt_3d_reached_l, & |
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| 190 | dz, topography, u_gtrans, v_gtrans |
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| 191 | |
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| 192 | USE grid_variables, & |
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| 193 | ONLY: dx, dy |
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| 194 | |
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| 195 | USE indices, & |
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| 196 | ONLY: nzb, nzt, wall_flags_0 |
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| 197 | |
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| 198 | USE kinds |
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| 199 | |
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| 200 | USE particle_attributes, & |
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| 201 | ONLY: block_offset, c_0, dt_min_part, grid_particles, iran_part, & |
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| 202 | log_z_z0, number_of_particles, number_of_sublayers, & |
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| 203 | particles, particle_groups, sgs_wf_part, & |
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| 204 | use_sgs_for_particles, vertical_particle_advection, z0_av_global |
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| 205 | |
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| 206 | USE statistics, & |
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| 207 | ONLY: hom |
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| 208 | |
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| 209 | USE surface_mod, & |
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| 210 | ONLY: get_topography_top_index_ji, surf_def_h, surf_lsm_h, surf_usm_h |
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| 211 | |
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| 212 | IMPLICIT NONE |
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| 213 | |
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| 214 | LOGICAL :: subbox_at_wall !< flag to see if the current subgridbox is adjacent to a wall |
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| 215 | |
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| 216 | INTEGER(iwp) :: i !< index variable along x |
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| 217 | INTEGER(iwp) :: ip !< index variable along x |
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| 218 | INTEGER(iwp) :: j !< index variable along y |
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| 219 | INTEGER(iwp) :: jp !< index variable along y |
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| 220 | INTEGER(iwp) :: k !< index variable along z |
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| 221 | INTEGER(iwp) :: k_wall !< vertical index of topography top |
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| 222 | INTEGER(iwp) :: kp !< index variable along z |
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| 223 | INTEGER(iwp) :: kw !< index variable along z |
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| 224 | INTEGER(iwp) :: n !< loop variable over all particles in a grid box |
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| 225 | INTEGER(iwp) :: nb !< block number particles are sorted in |
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| 226 | INTEGER(iwp) :: surf_start !< Index on surface data-type for current grid box |
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| 227 | |
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| 228 | INTEGER(iwp), DIMENSION(0:7) :: start_index !< start particle index for current block |
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| 229 | INTEGER(iwp), DIMENSION(0:7) :: end_index !< start particle index for current block |
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| 230 | |
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| 231 | REAL(wp) :: aa !< dummy argument for horizontal particle interpolation |
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| 232 | REAL(wp) :: bb !< dummy argument for horizontal particle interpolation |
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| 233 | REAL(wp) :: cc !< dummy argument for horizontal particle interpolation |
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| 234 | REAL(wp) :: d_z_p_z0 !< inverse of interpolation length for logarithmic interpolation |
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| 235 | REAL(wp) :: dd !< dummy argument for horizontal particle interpolation |
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| 236 | REAL(wp) :: de_dx_int_l !< x/y-interpolated TKE gradient (x) at particle position at lower vertical level |
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| 237 | REAL(wp) :: de_dx_int_u !< x/y-interpolated TKE gradient (x) at particle position at upper vertical level |
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| 238 | REAL(wp) :: de_dy_int_l !< x/y-interpolated TKE gradient (y) at particle position at lower vertical level |
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| 239 | REAL(wp) :: de_dy_int_u !< x/y-interpolated TKE gradient (y) at particle position at upper vertical level |
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| 240 | REAL(wp) :: de_dt !< temporal derivative of TKE experienced by the particle |
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| 241 | REAL(wp) :: de_dt_min !< lower level for temporal TKE derivative |
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| 242 | REAL(wp) :: de_dz_int_l !< x/y-interpolated TKE gradient (z) at particle position at lower vertical level |
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| 243 | REAL(wp) :: de_dz_int_u !< x/y-interpolated TKE gradient (z) at particle position at upper vertical level |
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| 244 | REAL(wp) :: diameter !< diamter of droplet |
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| 245 | REAL(wp) :: diss_int_l !< x/y-interpolated dissipation at particle position at lower vertical level |
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| 246 | REAL(wp) :: diss_int_u !< x/y-interpolated dissipation at particle position at upper vertical level |
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| 247 | REAL(wp) :: dt_particle_m !< previous particle time step |
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| 248 | REAL(wp) :: dz_temp !< dummy for the vertical grid spacing |
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| 249 | REAL(wp) :: e_int_l !< x/y-interpolated TKE at particle position at lower vertical level |
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| 250 | REAL(wp) :: e_int_u !< x/y-interpolated TKE at particle position at upper vertical level |
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| 251 | REAL(wp) :: e_mean_int !< horizontal mean TKE at particle height |
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| 252 | REAL(wp) :: exp_arg !< argument in the exponent - particle radius |
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| 253 | REAL(wp) :: exp_term !< exponent term |
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| 254 | REAL(wp) :: gg !< dummy argument for horizontal particle interpolation |
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| 255 | REAL(wp) :: height_p !< dummy argument for logarithmic interpolation |
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| 256 | REAL(wp) :: log_z_z0_int !< logarithmus used for surface_layer interpolation |
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| 257 | REAL(wp) :: random_gauss !< Gaussian-distributed random number used for SGS particle advection |
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| 258 | REAL(wp) :: RL !< Lagrangian autocorrelation coefficient |
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| 259 | REAL(wp) :: rg1 !< Gaussian distributed random number |
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| 260 | REAL(wp) :: rg2 !< Gaussian distributed random number |
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| 261 | REAL(wp) :: rg3 !< Gaussian distributed random number |
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| 262 | REAL(wp) :: sigma !< velocity standard deviation |
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| 263 | REAL(wp) :: u_int_l !< x/y-interpolated u-component at particle position at lower vertical level |
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| 264 | REAL(wp) :: u_int_u !< x/y-interpolated u-component at particle position at upper vertical level |
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| 265 | REAL(wp) :: us_int !< friction velocity at particle grid box |
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| 266 | REAL(wp) :: usws_int !< surface momentum flux (u component) at particle grid box |
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| 267 | REAL(wp) :: v_int_l !< x/y-interpolated v-component at particle position at lower vertical level |
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| 268 | REAL(wp) :: v_int_u !< x/y-interpolated v-component at particle position at upper vertical level |
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| 269 | REAL(wp) :: vsws_int !< surface momentum flux (u component) at particle grid box |
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| 270 | REAL(wp) :: vv_int !< dummy to compute interpolated mean SGS TKE, used to scale SGS advection |
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| 271 | REAL(wp) :: w_int_l !< x/y-interpolated w-component at particle position at lower vertical level |
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| 272 | REAL(wp) :: w_int_u !< x/y-interpolated w-component at particle position at upper vertical level |
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| 273 | REAL(wp) :: w_s !< terminal velocity of droplets |
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| 274 | REAL(wp) :: x !< dummy argument for horizontal particle interpolation |
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| 275 | REAL(wp) :: y !< dummy argument for horizontal particle interpolation |
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| 276 | REAL(wp) :: z_p !< surface layer height (0.5 dz) |
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| 277 | |
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| 278 | REAL(wp), PARAMETER :: a_rog = 9.65_wp !< parameter for fall velocity |
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| 279 | REAL(wp), PARAMETER :: b_rog = 10.43_wp !< parameter for fall velocity |
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| 280 | REAL(wp), PARAMETER :: c_rog = 0.6_wp !< parameter for fall velocity |
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| 281 | REAL(wp), PARAMETER :: k_cap_rog = 4.0_wp !< parameter for fall velocity |
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| 282 | REAL(wp), PARAMETER :: k_low_rog = 12.0_wp !< parameter for fall velocity |
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| 283 | REAL(wp), PARAMETER :: d0_rog = 0.745_wp !< separation diameter |
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| 284 | |
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| 285 | REAL(wp), DIMENSION(number_of_particles) :: term_1_2 !< flag to communicate whether a particle is near topography or not |
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| 286 | REAL(wp), DIMENSION(number_of_particles) :: dens_ratio !< ratio between the density of the fluid and the density of the particles |
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| 287 | REAL(wp), DIMENSION(number_of_particles) :: de_dx_int !< horizontal TKE gradient along x at particle position |
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| 288 | REAL(wp), DIMENSION(number_of_particles) :: de_dy_int !< horizontal TKE gradient along y at particle position |
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| 289 | REAL(wp), DIMENSION(number_of_particles) :: de_dz_int !< horizontal TKE gradient along z at particle position |
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| 290 | REAL(wp), DIMENSION(number_of_particles) :: diss_int !< dissipation at particle position |
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| 291 | REAL(wp), DIMENSION(number_of_particles) :: dt_gap !< remaining time until particle time integration reaches LES time |
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| 292 | REAL(wp), DIMENSION(number_of_particles) :: dt_particle !< particle time step |
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| 293 | REAL(wp), DIMENSION(number_of_particles) :: e_int !< TKE at particle position |
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| 294 | REAL(wp), DIMENSION(number_of_particles) :: fs_int !< weighting factor for subgrid-scale particle speed |
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| 295 | REAL(wp), DIMENSION(number_of_particles) :: lagr_timescale !< Lagrangian timescale |
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| 296 | REAL(wp), DIMENSION(number_of_particles) :: rvar1_temp !< SGS particle velocity - u-component |
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| 297 | REAL(wp), DIMENSION(number_of_particles) :: rvar2_temp !< SGS particle velocity - v-component |
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| 298 | REAL(wp), DIMENSION(number_of_particles) :: rvar3_temp !< SGS particle velocity - w-component |
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| 299 | REAL(wp), DIMENSION(number_of_particles) :: u_int !< u-component of particle speed |
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| 300 | REAL(wp), DIMENSION(number_of_particles) :: v_int !< v-component of particle speed |
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| 301 | REAL(wp), DIMENSION(number_of_particles) :: w_int !< w-component of particle speed |
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| 302 | REAL(wp), DIMENSION(number_of_particles) :: xv !< x-position |
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| 303 | REAL(wp), DIMENSION(number_of_particles) :: yv !< y-position |
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| 304 | REAL(wp), DIMENSION(number_of_particles) :: zv !< z-position |
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| 305 | |
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| 306 | REAL(wp), DIMENSION(number_of_particles, 3) :: rg !< vector of Gaussian distributed random numbers |
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| 307 | |
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| 308 | CALL cpu_log( log_point_s(44), 'lpm_advec', 'continue' ) |
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| 309 | |
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| 310 | ! |
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| 311 | !-- Determine height of Prandtl layer and distance between Prandtl-layer |
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| 312 | !-- height and horizontal mean roughness height, which are required for |
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| 313 | !-- vertical logarithmic interpolation of horizontal particle speeds |
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| 314 | !-- (for particles below first vertical grid level). |
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| 315 | z_p = zu(nzb+1) - zw(nzb) |
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| 316 | d_z_p_z0 = 1.0_wp / ( z_p - z0_av_global ) |
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| 317 | |
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| 318 | start_index = grid_particles(kp,jp,ip)%start_index |
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| 319 | end_index = grid_particles(kp,jp,ip)%end_index |
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| 320 | |
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| 321 | xv = particles(1:number_of_particles)%x |
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| 322 | yv = particles(1:number_of_particles)%y |
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| 323 | zv = particles(1:number_of_particles)%z |
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| 324 | |
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| 325 | DO nb = 0, 7 |
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| 326 | ! |
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| 327 | !-- Interpolate u velocity-component |
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| 328 | i = ip |
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| 329 | j = jp + block_offset(nb)%j_off |
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| 330 | k = kp + block_offset(nb)%k_off |
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| 331 | |
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| 332 | DO n = start_index(nb), end_index(nb) |
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| 333 | ! |
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| 334 | !-- Interpolation of the u velocity component onto particle position. |
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| 335 | !-- Particles are interpolation bi-linearly in the horizontal and a |
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| 336 | !-- linearly in the vertical. An exception is made for particles below |
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| 337 | !-- the first vertical grid level in case of a prandtl layer. In this |
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| 338 | !-- case the horizontal particle velocity components are determined using |
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| 339 | !-- Monin-Obukhov relations (if branch). |
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| 340 | !-- First, check if particle is located below first vertical grid level |
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| 341 | !-- above topography (Prandtl-layer height) |
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| 342 | !-- Determine vertical index of topography top |
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| 343 | k_wall = get_topography_top_index_ji( jp, ip, 's' ) |
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| 344 | |
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| 345 | IF ( constant_flux_layer .AND. zv(n) - zw(k_wall) < z_p ) THEN |
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| 346 | ! |
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| 347 | !-- Resolved-scale horizontal particle velocity is zero below z0. |
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| 348 | IF ( zv(n) - zw(k_wall) < z0_av_global ) THEN |
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| 349 | u_int(n) = 0.0_wp |
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| 350 | ELSE |
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| 351 | ! |
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| 352 | !-- Determine the sublayer. Further used as index. |
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| 353 | height_p = ( zv(n) - zw(k_wall) - z0_av_global ) & |
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| 354 | * REAL( number_of_sublayers, KIND=wp ) & |
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| 355 | * d_z_p_z0 |
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| 356 | ! |
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| 357 | !-- Calculate LOG(z/z0) for exact particle height. Therefore, |
|---|
| 358 | !-- interpolate linearly between precalculated logarithm. |
|---|
| 359 | log_z_z0_int = log_z_z0(INT(height_p)) & |
|---|
| 360 | + ( height_p - INT(height_p) ) & |
|---|
| 361 | * ( log_z_z0(INT(height_p)+1) & |
|---|
| 362 | - log_z_z0(INT(height_p)) & |
|---|
| 363 | ) |
|---|
| 364 | ! |
|---|
| 365 | !-- Get friction velocity and momentum flux from new surface data |
|---|
| 366 | !-- types. |
|---|
| 367 | IF ( surf_def_h(0)%start_index(jp,ip) <= & |
|---|
| 368 | surf_def_h(0)%end_index(jp,ip) ) THEN |
|---|
| 369 | surf_start = surf_def_h(0)%start_index(jp,ip) |
|---|
| 370 | !-- Limit friction velocity. In narrow canyons or holes the |
|---|
| 371 | !-- friction velocity can become very small, resulting in a too |
|---|
| 372 | !-- large particle speed. |
|---|
| 373 | us_int = MAX( surf_def_h(0)%us(surf_start), 0.01_wp ) |
|---|
| 374 | usws_int = surf_def_h(0)%usws(surf_start) |
|---|
| 375 | ELSEIF ( surf_lsm_h%start_index(jp,ip) <= & |
|---|
| 376 | surf_lsm_h%end_index(jp,ip) ) THEN |
|---|
| 377 | surf_start = surf_lsm_h%start_index(jp,ip) |
|---|
| 378 | us_int = MAX( surf_lsm_h%us(surf_start), 0.01_wp ) |
|---|
| 379 | usws_int = surf_lsm_h%usws(surf_start) |
|---|
| 380 | ELSEIF ( surf_usm_h%start_index(jp,ip) <= & |
|---|
| 381 | surf_usm_h%end_index(jp,ip) ) THEN |
|---|
| 382 | surf_start = surf_usm_h%start_index(jp,ip) |
|---|
| 383 | us_int = MAX( surf_usm_h%us(surf_start), 0.01_wp ) |
|---|
| 384 | usws_int = surf_usm_h%usws(surf_start) |
|---|
| 385 | ENDIF |
|---|
| 386 | |
|---|
| 387 | ! |
|---|
| 388 | !-- Neutral solution is applied for all situations, e.g. also for |
|---|
| 389 | !-- unstable and stable situations. Even though this is not exact |
|---|
| 390 | !-- this saves a lot of CPU time since several calls of intrinsic |
|---|
| 391 | !-- FORTRAN procedures (LOG, ATAN) are avoided, This is justified |
|---|
| 392 | !-- as sensitivity studies revealed no significant effect of |
|---|
| 393 | !-- using the neutral solution also for un/stable situations. |
|---|
| 394 | u_int(n) = -usws_int / ( us_int * kappa + 1E-10_wp ) & |
|---|
| 395 | * log_z_z0_int - u_gtrans |
|---|
| 396 | |
|---|
| 397 | ENDIF |
|---|
| 398 | ! |
|---|
| 399 | !-- Particle above the first grid level. Bi-linear interpolation in the |
|---|
| 400 | !-- horizontal and linear interpolation in the vertical direction. |
|---|
| 401 | ELSE |
|---|
| 402 | |
|---|
| 403 | x = xv(n) - i * dx |
|---|
| 404 | y = yv(n) + ( 0.5_wp - j ) * dy |
|---|
| 405 | aa = x**2 + y**2 |
|---|
| 406 | bb = ( dx - x )**2 + y**2 |
|---|
| 407 | cc = x**2 + ( dy - y )**2 |
|---|
| 408 | dd = ( dx - x )**2 + ( dy - y )**2 |
|---|
| 409 | gg = aa + bb + cc + dd |
|---|
| 410 | |
|---|
| 411 | u_int_l = ( ( gg - aa ) * u(k,j,i) + ( gg - bb ) * u(k,j,i+1) & |
|---|
| 412 | + ( gg - cc ) * u(k,j+1,i) + ( gg - dd ) * & |
|---|
| 413 | u(k,j+1,i+1) ) / ( 3.0_wp * gg ) - u_gtrans |
|---|
| 414 | |
|---|
| 415 | IF ( k == nzt ) THEN |
|---|
| 416 | u_int(n) = u_int_l |
|---|
| 417 | ELSE |
|---|
| 418 | u_int_u = ( ( gg-aa ) * u(k+1,j,i) + ( gg-bb ) * u(k+1,j,i+1) & |
|---|
| 419 | + ( gg-cc ) * u(k+1,j+1,i) + ( gg-dd ) * & |
|---|
| 420 | u(k+1,j+1,i+1) ) / ( 3.0_wp * gg ) - u_gtrans |
|---|
| 421 | u_int(n) = u_int_l + ( zv(n) - zu(k) ) / dzw(k+1) * & |
|---|
| 422 | ( u_int_u - u_int_l ) |
|---|
| 423 | ENDIF |
|---|
| 424 | |
|---|
| 425 | ENDIF |
|---|
| 426 | |
|---|
| 427 | ENDDO |
|---|
| 428 | ! |
|---|
| 429 | !-- Same procedure for interpolation of the v velocity-component |
|---|
| 430 | i = ip + block_offset(nb)%i_off |
|---|
| 431 | j = jp |
|---|
| 432 | k = kp + block_offset(nb)%k_off |
|---|
| 433 | |
|---|
| 434 | DO n = start_index(nb), end_index(nb) |
|---|
| 435 | |
|---|
| 436 | ! |
|---|
| 437 | !-- Determine vertical index of topography top |
|---|
| 438 | k_wall = get_topography_top_index_ji( jp,ip, 's' ) |
|---|
| 439 | |
|---|
| 440 | IF ( constant_flux_layer .AND. zv(n) - zw(k_wall) < z_p ) THEN |
|---|
| 441 | IF ( zv(n) - zw(k_wall) < z0_av_global ) THEN |
|---|
| 442 | ! |
|---|
| 443 | !-- Resolved-scale horizontal particle velocity is zero below z0. |
|---|
| 444 | v_int(n) = 0.0_wp |
|---|
| 445 | ELSE |
|---|
| 446 | ! |
|---|
| 447 | !-- Determine the sublayer. Further used as index. Please note, |
|---|
| 448 | !-- logarithmus can not be reused from above, as in in case of |
|---|
| 449 | !-- topography particle on u-grid can be above surface-layer height, |
|---|
| 450 | !-- whereas it can be below on v-grid. |
|---|
| 451 | height_p = ( zv(n) - zw(k_wall) - z0_av_global ) & |
|---|
| 452 | * REAL( number_of_sublayers, KIND=wp ) & |
|---|
| 453 | * d_z_p_z0 |
|---|
| 454 | ! |
|---|
| 455 | !-- Calculate LOG(z/z0) for exact particle height. Therefore, |
|---|
| 456 | !-- interpolate linearly between precalculated logarithm. |
|---|
| 457 | log_z_z0_int = log_z_z0(INT(height_p)) & |
|---|
| 458 | + ( height_p - INT(height_p) ) & |
|---|
| 459 | * ( log_z_z0(INT(height_p)+1) & |
|---|
| 460 | - log_z_z0(INT(height_p)) & |
|---|
| 461 | ) |
|---|
| 462 | ! |
|---|
| 463 | !-- Get friction velocity and momentum flux from new surface data |
|---|
| 464 | !-- types. |
|---|
| 465 | IF ( surf_def_h(0)%start_index(jp,ip) <= & |
|---|
| 466 | surf_def_h(0)%end_index(jp,ip) ) THEN |
|---|
| 467 | surf_start = surf_def_h(0)%start_index(jp,ip) |
|---|
| 468 | !-- Limit friction velocity. In narrow canyons or holes the |
|---|
| 469 | !-- friction velocity can become very small, resulting in a too |
|---|
| 470 | !-- large particle speed. |
|---|
| 471 | us_int = MAX( surf_def_h(0)%us(surf_start), 0.01_wp ) |
|---|
| 472 | vsws_int = surf_def_h(0)%vsws(surf_start) |
|---|
| 473 | ELSEIF ( surf_lsm_h%start_index(jp,ip) <= & |
|---|
| 474 | surf_lsm_h%end_index(jp,ip) ) THEN |
|---|
| 475 | surf_start = surf_lsm_h%start_index(jp,ip) |
|---|
| 476 | us_int = MAX( surf_lsm_h%us(surf_start), 0.01_wp ) |
|---|
| 477 | vsws_int = surf_lsm_h%vsws(surf_start) |
|---|
| 478 | ELSEIF ( surf_usm_h%start_index(jp,ip) <= & |
|---|
| 479 | surf_usm_h%end_index(jp,ip) ) THEN |
|---|
| 480 | surf_start = surf_usm_h%start_index(jp,ip) |
|---|
| 481 | us_int = MAX( surf_usm_h%us(surf_start), 0.01_wp ) |
|---|
| 482 | vsws_int = surf_usm_h%vsws(surf_start) |
|---|
| 483 | ENDIF |
|---|
| 484 | ! |
|---|
| 485 | !-- Neutral solution is applied for all situations, e.g. also for |
|---|
| 486 | !-- unstable and stable situations. Even though this is not exact |
|---|
| 487 | !-- this saves a lot of CPU time since several calls of intrinsic |
|---|
| 488 | !-- FORTRAN procedures (LOG, ATAN) are avoided, This is justified |
|---|
| 489 | !-- as sensitivity studies revealed no significant effect of |
|---|
| 490 | !-- using the neutral solution also for un/stable situations. |
|---|
| 491 | v_int(n) = -vsws_int / ( us_int * kappa + 1E-10_wp ) & |
|---|
| 492 | * log_z_z0_int - v_gtrans |
|---|
| 493 | |
|---|
| 494 | ENDIF |
|---|
| 495 | |
|---|
| 496 | ELSE |
|---|
| 497 | x = xv(n) + ( 0.5_wp - i ) * dx |
|---|
| 498 | y = yv(n) - j * dy |
|---|
| 499 | aa = x**2 + y**2 |
|---|
| 500 | bb = ( dx - x )**2 + y**2 |
|---|
| 501 | cc = x**2 + ( dy - y )**2 |
|---|
| 502 | dd = ( dx - x )**2 + ( dy - y )**2 |
|---|
| 503 | gg = aa + bb + cc + dd |
|---|
| 504 | |
|---|
| 505 | v_int_l = ( ( gg - aa ) * v(k,j,i) + ( gg - bb ) * v(k,j,i+1) & |
|---|
| 506 | + ( gg - cc ) * v(k,j+1,i) + ( gg - dd ) * v(k,j+1,i+1) & |
|---|
| 507 | ) / ( 3.0_wp * gg ) - v_gtrans |
|---|
| 508 | |
|---|
| 509 | IF ( k == nzt ) THEN |
|---|
| 510 | v_int(n) = v_int_l |
|---|
| 511 | ELSE |
|---|
| 512 | v_int_u = ( ( gg-aa ) * v(k+1,j,i) + ( gg-bb ) * v(k+1,j,i+1) & |
|---|
| 513 | + ( gg-cc ) * v(k+1,j+1,i) + ( gg-dd ) * v(k+1,j+1,i+1) & |
|---|
| 514 | ) / ( 3.0_wp * gg ) - v_gtrans |
|---|
| 515 | v_int(n) = v_int_l + ( zv(n) - zu(k) ) / dzw(k+1) * & |
|---|
| 516 | ( v_int_u - v_int_l ) |
|---|
| 517 | ENDIF |
|---|
| 518 | |
|---|
| 519 | ENDIF |
|---|
| 520 | |
|---|
| 521 | ENDDO |
|---|
| 522 | ! |
|---|
| 523 | !-- Same procedure for interpolation of the w velocity-component |
|---|
| 524 | i = ip + block_offset(nb)%i_off |
|---|
| 525 | j = jp + block_offset(nb)%j_off |
|---|
| 526 | k = kp - 1 |
|---|
| 527 | |
|---|
| 528 | DO n = start_index(nb), end_index(nb) |
|---|
| 529 | |
|---|
| 530 | IF ( vertical_particle_advection(particles(n)%group) ) THEN |
|---|
| 531 | |
|---|
| 532 | x = xv(n) + ( 0.5_wp - i ) * dx |
|---|
| 533 | y = yv(n) + ( 0.5_wp - j ) * dy |
|---|
| 534 | aa = x**2 + y**2 |
|---|
| 535 | bb = ( dx - x )**2 + y**2 |
|---|
| 536 | cc = x**2 + ( dy - y )**2 |
|---|
| 537 | dd = ( dx - x )**2 + ( dy - y )**2 |
|---|
| 538 | gg = aa + bb + cc + dd |
|---|
| 539 | |
|---|
| 540 | w_int_l = ( ( gg - aa ) * w(k,j,i) + ( gg - bb ) * w(k,j,i+1) & |
|---|
| 541 | + ( gg - cc ) * w(k,j+1,i) + ( gg - dd ) * w(k,j+1,i+1) & |
|---|
| 542 | ) / ( 3.0_wp * gg ) |
|---|
| 543 | |
|---|
| 544 | IF ( k == nzt ) THEN |
|---|
| 545 | w_int(n) = w_int_l |
|---|
| 546 | ELSE |
|---|
| 547 | w_int_u = ( ( gg-aa ) * w(k+1,j,i) + & |
|---|
| 548 | ( gg-bb ) * w(k+1,j,i+1) + & |
|---|
| 549 | ( gg-cc ) * w(k+1,j+1,i) + & |
|---|
| 550 | ( gg-dd ) * w(k+1,j+1,i+1) & |
|---|
| 551 | ) / ( 3.0_wp * gg ) |
|---|
| 552 | w_int(n) = w_int_l + ( zv(n) - zw(k) ) / dzw(k+1) * & |
|---|
| 553 | ( w_int_u - w_int_l ) |
|---|
| 554 | ENDIF |
|---|
| 555 | |
|---|
| 556 | ELSE |
|---|
| 557 | |
|---|
| 558 | w_int(n) = 0.0_wp |
|---|
| 559 | |
|---|
| 560 | ENDIF |
|---|
| 561 | |
|---|
| 562 | ENDDO |
|---|
| 563 | |
|---|
| 564 | ENDDO |
|---|
| 565 | |
|---|
| 566 | !-- Interpolate and calculate quantities needed for calculating the SGS |
|---|
| 567 | !-- velocities |
|---|
| 568 | IF ( use_sgs_for_particles .AND. .NOT. cloud_droplets ) THEN |
|---|
| 569 | |
|---|
| 570 | DO nb = 0,7 |
|---|
| 571 | |
|---|
| 572 | subbox_at_wall = .FALSE. |
|---|
| 573 | ! |
|---|
| 574 | !-- In case of topography check if subbox is adjacent to a wall |
|---|
| 575 | IF ( .NOT. topography == 'flat' ) THEN |
|---|
| 576 | i = ip + MERGE( -1_iwp , 1_iwp, BTEST( nb, 2 ) ) |
|---|
| 577 | j = jp + MERGE( -1_iwp , 1_iwp, BTEST( nb, 1 ) ) |
|---|
| 578 | k = kp + MERGE( -1_iwp , 1_iwp, BTEST( nb, 0 ) ) |
|---|
| 579 | IF ( .NOT. BTEST(wall_flags_0(k, jp, ip), 0) .OR. & |
|---|
| 580 | .NOT. BTEST(wall_flags_0(kp, j, ip), 0) .OR. & |
|---|
| 581 | .NOT. BTEST(wall_flags_0(kp, jp, i ), 0) ) & |
|---|
| 582 | THEN |
|---|
| 583 | subbox_at_wall = .TRUE. |
|---|
| 584 | ENDIF |
|---|
| 585 | ENDIF |
|---|
| 586 | IF ( subbox_at_wall ) THEN |
|---|
| 587 | e_int(start_index(nb):end_index(nb)) = e(kp,jp,ip) |
|---|
| 588 | diss_int(start_index(nb):end_index(nb)) = diss(kp,jp,ip) |
|---|
| 589 | de_dx_int(start_index(nb):end_index(nb)) = de_dx(kp,jp,ip) |
|---|
| 590 | de_dy_int(start_index(nb):end_index(nb)) = de_dy(kp,jp,ip) |
|---|
| 591 | de_dz_int(start_index(nb):end_index(nb)) = de_dz(kp,jp,ip) |
|---|
| 592 | ! |
|---|
| 593 | !-- Set flag for stochastic equation. |
|---|
| 594 | term_1_2(start_index(nb):end_index(nb)) = 0.0_wp |
|---|
| 595 | ELSE |
|---|
| 596 | i = ip + block_offset(nb)%i_off |
|---|
| 597 | j = jp + block_offset(nb)%j_off |
|---|
| 598 | k = kp + block_offset(nb)%k_off |
|---|
| 599 | |
|---|
| 600 | DO n = start_index(nb), end_index(nb) |
|---|
| 601 | ! |
|---|
| 602 | !-- Interpolate TKE |
|---|
| 603 | x = xv(n) + ( 0.5_wp - i ) * dx |
|---|
| 604 | y = yv(n) + ( 0.5_wp - j ) * dy |
|---|
| 605 | aa = x**2 + y**2 |
|---|
| 606 | bb = ( dx - x )**2 + y**2 |
|---|
| 607 | cc = x**2 + ( dy - y )**2 |
|---|
| 608 | dd = ( dx - x )**2 + ( dy - y )**2 |
|---|
| 609 | gg = aa + bb + cc + dd |
|---|
| 610 | |
|---|
| 611 | e_int_l = ( ( gg-aa ) * e(k,j,i) + ( gg-bb ) * e(k,j,i+1) & |
|---|
| 612 | + ( gg-cc ) * e(k,j+1,i) + ( gg-dd ) * e(k,j+1,i+1) & |
|---|
| 613 | ) / ( 3.0_wp * gg ) |
|---|
| 614 | |
|---|
| 615 | IF ( k+1 == nzt+1 ) THEN |
|---|
| 616 | e_int(n) = e_int_l |
|---|
| 617 | ELSE |
|---|
| 618 | e_int_u = ( ( gg - aa ) * e(k+1,j,i) + & |
|---|
| 619 | ( gg - bb ) * e(k+1,j,i+1) + & |
|---|
| 620 | ( gg - cc ) * e(k+1,j+1,i) + & |
|---|
| 621 | ( gg - dd ) * e(k+1,j+1,i+1) & |
|---|
| 622 | ) / ( 3.0_wp * gg ) |
|---|
| 623 | e_int(n) = e_int_l + ( zv(n) - zu(k) ) / dzw(k+1) * & |
|---|
| 624 | ( e_int_u - e_int_l ) |
|---|
| 625 | ENDIF |
|---|
| 626 | ! |
|---|
| 627 | !-- Needed to avoid NaN particle velocities (this might not be |
|---|
| 628 | !-- required any more) |
|---|
| 629 | IF ( e_int(n) <= 0.0_wp ) THEN |
|---|
| 630 | e_int(n) = 1.0E-20_wp |
|---|
| 631 | ENDIF |
|---|
| 632 | ! |
|---|
| 633 | !-- Interpolate the TKE gradient along x (adopt incides i,j,k and |
|---|
| 634 | !-- all position variables from above (TKE)) |
|---|
| 635 | de_dx_int_l = ( ( gg - aa ) * de_dx(k,j,i) + & |
|---|
| 636 | ( gg - bb ) * de_dx(k,j,i+1) + & |
|---|
| 637 | ( gg - cc ) * de_dx(k,j+1,i) + & |
|---|
| 638 | ( gg - dd ) * de_dx(k,j+1,i+1) & |
|---|
| 639 | ) / ( 3.0_wp * gg ) |
|---|
| 640 | |
|---|
| 641 | IF ( ( k+1 == nzt+1 ) .OR. ( k == nzb ) ) THEN |
|---|
| 642 | de_dx_int(n) = de_dx_int_l |
|---|
| 643 | ELSE |
|---|
| 644 | de_dx_int_u = ( ( gg - aa ) * de_dx(k+1,j,i) + & |
|---|
| 645 | ( gg - bb ) * de_dx(k+1,j,i+1) + & |
|---|
| 646 | ( gg - cc ) * de_dx(k+1,j+1,i) + & |
|---|
| 647 | ( gg - dd ) * de_dx(k+1,j+1,i+1) & |
|---|
| 648 | ) / ( 3.0_wp * gg ) |
|---|
| 649 | de_dx_int(n) = de_dx_int_l + ( zv(n) - zu(k) ) / dzw(k+1) * & |
|---|
| 650 | ( de_dx_int_u - de_dx_int_l ) |
|---|
| 651 | ENDIF |
|---|
| 652 | ! |
|---|
| 653 | !-- Interpolate the TKE gradient along y |
|---|
| 654 | de_dy_int_l = ( ( gg - aa ) * de_dy(k,j,i) + & |
|---|
| 655 | ( gg - bb ) * de_dy(k,j,i+1) + & |
|---|
| 656 | ( gg - cc ) * de_dy(k,j+1,i) + & |
|---|
| 657 | ( gg - dd ) * de_dy(k,j+1,i+1) & |
|---|
| 658 | ) / ( 3.0_wp * gg ) |
|---|
| 659 | IF ( ( k+1 == nzt+1 ) .OR. ( k == nzb ) ) THEN |
|---|
| 660 | de_dy_int(n) = de_dy_int_l |
|---|
| 661 | ELSE |
|---|
| 662 | de_dy_int_u = ( ( gg - aa ) * de_dy(k+1,j,i) + & |
|---|
| 663 | ( gg - bb ) * de_dy(k+1,j,i+1) + & |
|---|
| 664 | ( gg - cc ) * de_dy(k+1,j+1,i) + & |
|---|
| 665 | ( gg - dd ) * de_dy(k+1,j+1,i+1) & |
|---|
| 666 | ) / ( 3.0_wp * gg ) |
|---|
| 667 | de_dy_int(n) = de_dy_int_l + ( zv(n) - zu(k) ) / dzw(k+1) * & |
|---|
| 668 | ( de_dy_int_u - de_dy_int_l ) |
|---|
| 669 | ENDIF |
|---|
| 670 | |
|---|
| 671 | ! |
|---|
| 672 | !-- Interpolate the TKE gradient along z |
|---|
| 673 | IF ( zv(n) < 0.5_wp * dz(1) ) THEN |
|---|
| 674 | de_dz_int(n) = 0.0_wp |
|---|
| 675 | ELSE |
|---|
| 676 | de_dz_int_l = ( ( gg - aa ) * de_dz(k,j,i) + & |
|---|
| 677 | ( gg - bb ) * de_dz(k,j,i+1) + & |
|---|
| 678 | ( gg - cc ) * de_dz(k,j+1,i) + & |
|---|
| 679 | ( gg - dd ) * de_dz(k,j+1,i+1) & |
|---|
| 680 | ) / ( 3.0_wp * gg ) |
|---|
| 681 | |
|---|
| 682 | IF ( ( k+1 == nzt+1 ) .OR. ( k == nzb ) ) THEN |
|---|
| 683 | de_dz_int(n) = de_dz_int_l |
|---|
| 684 | ELSE |
|---|
| 685 | de_dz_int_u = ( ( gg - aa ) * de_dz(k+1,j,i) + & |
|---|
| 686 | ( gg - bb ) * de_dz(k+1,j,i+1) + & |
|---|
| 687 | ( gg - cc ) * de_dz(k+1,j+1,i) + & |
|---|
| 688 | ( gg - dd ) * de_dz(k+1,j+1,i+1) & |
|---|
| 689 | ) / ( 3.0_wp * gg ) |
|---|
| 690 | de_dz_int(n) = de_dz_int_l + ( zv(n) - zu(k) ) / dzw(k+1) * & |
|---|
| 691 | ( de_dz_int_u - de_dz_int_l ) |
|---|
| 692 | ENDIF |
|---|
| 693 | ENDIF |
|---|
| 694 | |
|---|
| 695 | ! |
|---|
| 696 | !-- Interpolate the dissipation of TKE |
|---|
| 697 | diss_int_l = ( ( gg - aa ) * diss(k,j,i) + & |
|---|
| 698 | ( gg - bb ) * diss(k,j,i+1) + & |
|---|
| 699 | ( gg - cc ) * diss(k,j+1,i) + & |
|---|
| 700 | ( gg - dd ) * diss(k,j+1,i+1) & |
|---|
| 701 | ) / ( 3.0_wp * gg ) |
|---|
| 702 | |
|---|
| 703 | IF ( k == nzt ) THEN |
|---|
| 704 | diss_int(n) = diss_int_l |
|---|
| 705 | ELSE |
|---|
| 706 | diss_int_u = ( ( gg - aa ) * diss(k+1,j,i) + & |
|---|
| 707 | ( gg - bb ) * diss(k+1,j,i+1) + & |
|---|
| 708 | ( gg - cc ) * diss(k+1,j+1,i) + & |
|---|
| 709 | ( gg - dd ) * diss(k+1,j+1,i+1) & |
|---|
| 710 | ) / ( 3.0_wp * gg ) |
|---|
| 711 | diss_int(n) = diss_int_l + ( zv(n) - zu(k) ) / dzw(k+1) * & |
|---|
| 712 | ( diss_int_u - diss_int_l ) |
|---|
| 713 | ENDIF |
|---|
| 714 | |
|---|
| 715 | ! |
|---|
| 716 | !-- Set flag for stochastic equation. |
|---|
| 717 | term_1_2(n) = 1.0_wp |
|---|
| 718 | ENDDO |
|---|
| 719 | ENDIF |
|---|
| 720 | ENDDO |
|---|
| 721 | |
|---|
| 722 | DO nb = 0,7 |
|---|
| 723 | i = ip + block_offset(nb)%i_off |
|---|
| 724 | j = jp + block_offset(nb)%j_off |
|---|
| 725 | k = kp + block_offset(nb)%k_off |
|---|
| 726 | |
|---|
| 727 | DO n = start_index(nb), end_index(nb) |
|---|
| 728 | ! |
|---|
| 729 | !-- Vertical interpolation of the horizontally averaged SGS TKE and |
|---|
| 730 | !-- resolved-scale velocity variances and use the interpolated values |
|---|
| 731 | !-- to calculate the coefficient fs, which is a measure of the ratio |
|---|
| 732 | !-- of the subgrid-scale turbulent kinetic energy to the total amount |
|---|
| 733 | !-- of turbulent kinetic energy. |
|---|
| 734 | IF ( k == 0 ) THEN |
|---|
| 735 | e_mean_int = hom(0,1,8,0) |
|---|
| 736 | ELSE |
|---|
| 737 | e_mean_int = hom(k,1,8,0) + & |
|---|
| 738 | ( hom(k+1,1,8,0) - hom(k,1,8,0) ) / & |
|---|
| 739 | ( zu(k+1) - zu(k) ) * & |
|---|
| 740 | ( zv(n) - zu(k) ) |
|---|
| 741 | ENDIF |
|---|
| 742 | |
|---|
| 743 | kw = kp - 1 |
|---|
| 744 | |
|---|
| 745 | IF ( k == 0 ) THEN |
|---|
| 746 | aa = hom(k+1,1,30,0) * ( zv(n) / & |
|---|
| 747 | ( 0.5_wp * ( zu(k+1) - zu(k) ) ) ) |
|---|
| 748 | bb = hom(k+1,1,31,0) * ( zv(n) / & |
|---|
| 749 | ( 0.5_wp * ( zu(k+1) - zu(k) ) ) ) |
|---|
| 750 | cc = hom(kw+1,1,32,0) * ( zv(n) / & |
|---|
| 751 | ( 1.0_wp * ( zw(kw+1) - zw(kw) ) ) ) |
|---|
| 752 | ELSE |
|---|
| 753 | aa = hom(k,1,30,0) + ( hom(k+1,1,30,0) - hom(k,1,30,0) ) * & |
|---|
| 754 | ( ( zv(n) - zu(k) ) / ( zu(k+1) - zu(k) ) ) |
|---|
| 755 | bb = hom(k,1,31,0) + ( hom(k+1,1,31,0) - hom(k,1,31,0) ) * & |
|---|
| 756 | ( ( zv(n) - zu(k) ) / ( zu(k+1) - zu(k) ) ) |
|---|
| 757 | cc = hom(kw,1,32,0) + ( hom(kw+1,1,32,0)-hom(kw,1,32,0) ) * & |
|---|
| 758 | ( ( zv(n) - zw(kw) ) / ( zw(kw+1)-zw(kw) ) ) |
|---|
| 759 | ENDIF |
|---|
| 760 | |
|---|
| 761 | vv_int = ( 1.0_wp / 3.0_wp ) * ( aa + bb + cc ) |
|---|
| 762 | ! |
|---|
| 763 | !-- Needed to avoid NaN particle velocities. The value of 1.0 is just |
|---|
| 764 | !-- an educated guess for the given case. |
|---|
| 765 | IF ( vv_int + ( 2.0_wp / 3.0_wp ) * e_mean_int == 0.0_wp ) THEN |
|---|
| 766 | fs_int(n) = 1.0_wp |
|---|
| 767 | ELSE |
|---|
| 768 | fs_int(n) = ( 2.0_wp / 3.0_wp ) * e_mean_int / & |
|---|
| 769 | ( vv_int + ( 2.0_wp / 3.0_wp ) * e_mean_int ) |
|---|
| 770 | ENDIF |
|---|
| 771 | |
|---|
| 772 | ENDDO |
|---|
| 773 | ENDDO |
|---|
| 774 | |
|---|
| 775 | DO nb = 0, 7 |
|---|
| 776 | DO n = start_index(nb), end_index(nb) |
|---|
| 777 | rg(n,1) = random_gauss( iran_part, 5.0_wp ) |
|---|
| 778 | rg(n,2) = random_gauss( iran_part, 5.0_wp ) |
|---|
| 779 | rg(n,3) = random_gauss( iran_part, 5.0_wp ) |
|---|
| 780 | ENDDO |
|---|
| 781 | ENDDO |
|---|
| 782 | |
|---|
| 783 | DO nb = 0, 7 |
|---|
| 784 | DO n = start_index(nb), end_index(nb) |
|---|
| 785 | |
|---|
| 786 | ! |
|---|
| 787 | !-- Calculate the Lagrangian timescale according to Weil et al. (2004). |
|---|
| 788 | lagr_timescale(n) = ( 4.0_wp * e_int(n) + 1E-20_wp ) / & |
|---|
| 789 | ( 3.0_wp * fs_int(n) * c_0 * diss_int(n) + 1E-20_wp ) |
|---|
| 790 | |
|---|
| 791 | ! |
|---|
| 792 | !-- Calculate the next particle timestep. dt_gap is the time needed to |
|---|
| 793 | !-- complete the current LES timestep. |
|---|
| 794 | dt_gap(n) = dt_3d - particles(n)%dt_sum |
|---|
| 795 | dt_particle(n) = MIN( dt_3d, 0.025_wp * lagr_timescale(n), dt_gap(n) ) |
|---|
| 796 | particles(n)%aux1 = lagr_timescale(n) |
|---|
| 797 | particles(n)%aux2 = dt_gap(n) |
|---|
| 798 | ! |
|---|
| 799 | !-- The particle timestep should not be too small in order to prevent |
|---|
| 800 | !-- the number of particle timesteps of getting too large |
|---|
| 801 | IF ( dt_particle(n) < dt_min_part .AND. dt_min_part < dt_gap(n) ) THEN |
|---|
| 802 | dt_particle(n) = dt_min_part |
|---|
| 803 | ENDIF |
|---|
| 804 | rvar1_temp(n) = particles(n)%rvar1 |
|---|
| 805 | rvar2_temp(n) = particles(n)%rvar2 |
|---|
| 806 | rvar3_temp(n) = particles(n)%rvar3 |
|---|
| 807 | ! |
|---|
| 808 | !-- Calculate the SGS velocity components |
|---|
| 809 | IF ( particles(n)%age == 0.0_wp ) THEN |
|---|
| 810 | ! |
|---|
| 811 | !-- For new particles the SGS components are derived from the SGS |
|---|
| 812 | !-- TKE. Limit the Gaussian random number to the interval |
|---|
| 813 | !-- [-5.0*sigma, 5.0*sigma] in order to prevent the SGS velocities |
|---|
| 814 | !-- from becoming unrealistically large. |
|---|
| 815 | rvar1_temp(n) = SQRT( 2.0_wp * sgs_wf_part * e_int(n) & |
|---|
| 816 | + 1E-20_wp ) * ( rg(n,1) - 1.0_wp ) |
|---|
| 817 | rvar2_temp(n) = SQRT( 2.0_wp * sgs_wf_part * e_int(n) & |
|---|
| 818 | + 1E-20_wp ) * ( rg(n,2) - 1.0_wp ) |
|---|
| 819 | rvar3_temp(n) = SQRT( 2.0_wp * sgs_wf_part * e_int(n) & |
|---|
| 820 | + 1E-20_wp ) * ( rg(n,3) - 1.0_wp ) |
|---|
| 821 | |
|---|
| 822 | ELSE |
|---|
| 823 | ! |
|---|
| 824 | !-- Restriction of the size of the new timestep: compared to the |
|---|
| 825 | !-- previous timestep the increase must not exceed 200%. First, |
|---|
| 826 | !-- check if age > age_m, in order to prevent that particles get zero |
|---|
| 827 | !-- timestep. |
|---|
| 828 | dt_particle_m = MERGE( dt_particle(n), & |
|---|
| 829 | particles(n)%age - particles(n)%age_m, & |
|---|
| 830 | particles(n)%age - particles(n)%age_m < & |
|---|
| 831 | 1E-8_wp ) |
|---|
| 832 | IF ( dt_particle(n) > 2.0_wp * dt_particle_m ) THEN |
|---|
| 833 | dt_particle(n) = 2.0_wp * dt_particle_m |
|---|
| 834 | ENDIF |
|---|
| 835 | |
|---|
| 836 | !-- For old particles the SGS components are correlated with the |
|---|
| 837 | !-- values from the previous timestep. Random numbers have also to |
|---|
| 838 | !-- be limited (see above). |
|---|
| 839 | !-- As negative values for the subgrid TKE are not allowed, the |
|---|
| 840 | !-- change of the subgrid TKE with time cannot be smaller than |
|---|
| 841 | !-- -e_int(n)/dt_particle. This value is used as a lower boundary |
|---|
| 842 | !-- value for the change of TKE |
|---|
| 843 | de_dt_min = - e_int(n) / dt_particle(n) |
|---|
| 844 | |
|---|
| 845 | de_dt = ( e_int(n) - particles(n)%e_m ) / dt_particle_m |
|---|
| 846 | |
|---|
| 847 | IF ( de_dt < de_dt_min ) THEN |
|---|
| 848 | de_dt = de_dt_min |
|---|
| 849 | ENDIF |
|---|
| 850 | |
|---|
| 851 | CALL weil_stochastic_eq(rvar1_temp(n), fs_int(n), e_int(n),& |
|---|
| 852 | de_dx_int(n), de_dt, diss_int(n), & |
|---|
| 853 | dt_particle(n), rg(n,1), term_1_2(n) ) |
|---|
| 854 | |
|---|
| 855 | CALL weil_stochastic_eq(rvar2_temp(n), fs_int(n), e_int(n),& |
|---|
| 856 | de_dy_int(n), de_dt, diss_int(n), & |
|---|
| 857 | dt_particle(n), rg(n,2), term_1_2(n) ) |
|---|
| 858 | |
|---|
| 859 | CALL weil_stochastic_eq(rvar3_temp(n), fs_int(n), e_int(n),& |
|---|
| 860 | de_dz_int(n), de_dt, diss_int(n), & |
|---|
| 861 | dt_particle(n), rg(n,3), term_1_2(n) ) |
|---|
| 862 | |
|---|
| 863 | ENDIF |
|---|
| 864 | |
|---|
| 865 | ENDDO |
|---|
| 866 | ENDDO |
|---|
| 867 | ! |
|---|
| 868 | !-- Check if the added SGS velocities result in a violation of the CFL- |
|---|
| 869 | !-- criterion. If yes choose a smaller timestep based on the new velocities |
|---|
| 870 | !-- and calculate SGS velocities again |
|---|
| 871 | dz_temp = zw(kp)-zw(kp-1) |
|---|
| 872 | |
|---|
| 873 | DO nb = 0, 7 |
|---|
| 874 | DO n = start_index(nb), end_index(nb) |
|---|
| 875 | IF ( .NOT. particles(n)%age == 0.0_wp .AND. & |
|---|
| 876 | (ABS( u_int(n) + rvar1_temp(n) ) > (dx/dt_particle(n)) .OR. & |
|---|
| 877 | ABS( v_int(n) + rvar2_temp(n) ) > (dy/dt_particle(n)) .OR. & |
|---|
| 878 | ABS( w_int(n) + rvar3_temp(n) ) > (dz_temp/dt_particle(n)))) THEN |
|---|
| 879 | |
|---|
| 880 | dt_particle(n) = 0.9_wp * MIN( & |
|---|
| 881 | ( dx / ABS( u_int(n) + rvar1_temp(n) ) ), & |
|---|
| 882 | ( dy / ABS( v_int(n) + rvar2_temp(n) ) ), & |
|---|
| 883 | ( dz_temp / ABS( w_int(n) + rvar3_temp(n) ) ) ) |
|---|
| 884 | |
|---|
| 885 | ! |
|---|
| 886 | !-- Reset temporary SGS velocites to "current" ones |
|---|
| 887 | rvar1_temp(n) = particles(n)%rvar1 |
|---|
| 888 | rvar2_temp(n) = particles(n)%rvar2 |
|---|
| 889 | rvar3_temp(n) = particles(n)%rvar3 |
|---|
| 890 | |
|---|
| 891 | de_dt_min = - e_int(n) / dt_particle(n) |
|---|
| 892 | |
|---|
| 893 | de_dt = ( e_int(n) - particles(n)%e_m ) / dt_particle_m |
|---|
| 894 | |
|---|
| 895 | IF ( de_dt < de_dt_min ) THEN |
|---|
| 896 | de_dt = de_dt_min |
|---|
| 897 | ENDIF |
|---|
| 898 | |
|---|
| 899 | CALL weil_stochastic_eq(rvar1_temp(n), fs_int(n), e_int(n),& |
|---|
| 900 | de_dx_int(n), de_dt, diss_int(n), & |
|---|
| 901 | dt_particle(n), rg(n,1), term_1_2(n) ) |
|---|
| 902 | |
|---|
| 903 | CALL weil_stochastic_eq(rvar2_temp(n), fs_int(n), e_int(n),& |
|---|
| 904 | de_dy_int(n), de_dt, diss_int(n), & |
|---|
| 905 | dt_particle(n), rg(n,2), term_1_2(n) ) |
|---|
| 906 | |
|---|
| 907 | CALL weil_stochastic_eq(rvar3_temp(n), fs_int(n), e_int(n),& |
|---|
| 908 | de_dz_int(n), de_dt, diss_int(n), & |
|---|
| 909 | dt_particle(n), rg(n,3), term_1_2(n) ) |
|---|
| 910 | ENDIF |
|---|
| 911 | |
|---|
| 912 | ! |
|---|
| 913 | !-- Update particle velocites |
|---|
| 914 | particles(n)%rvar1 = rvar1_temp(n) |
|---|
| 915 | particles(n)%rvar2 = rvar2_temp(n) |
|---|
| 916 | particles(n)%rvar3 = rvar3_temp(n) |
|---|
| 917 | u_int(n) = u_int(n) + particles(n)%rvar1 |
|---|
| 918 | v_int(n) = v_int(n) + particles(n)%rvar2 |
|---|
| 919 | w_int(n) = w_int(n) + particles(n)%rvar3 |
|---|
| 920 | ! |
|---|
| 921 | !-- Store the SGS TKE of the current timelevel which is needed for |
|---|
| 922 | !-- for calculating the SGS particle velocities at the next timestep |
|---|
| 923 | particles(n)%e_m = e_int(n) |
|---|
| 924 | ENDDO |
|---|
| 925 | ENDDO |
|---|
| 926 | |
|---|
| 927 | ELSE |
|---|
| 928 | ! |
|---|
| 929 | !-- If no SGS velocities are used, only the particle timestep has to |
|---|
| 930 | !-- be set |
|---|
| 931 | dt_particle = dt_3d |
|---|
| 932 | |
|---|
| 933 | ENDIF |
|---|
| 934 | |
|---|
| 935 | dens_ratio = particle_groups(particles(1:number_of_particles)%group)%density_ratio |
|---|
| 936 | |
|---|
| 937 | IF ( ANY( dens_ratio == 0.0_wp ) ) THEN |
|---|
| 938 | DO nb = 0, 7 |
|---|
| 939 | DO n = start_index(nb), end_index(nb) |
|---|
| 940 | |
|---|
| 941 | ! |
|---|
| 942 | !-- Particle advection |
|---|
| 943 | IF ( dens_ratio(n) == 0.0_wp ) THEN |
|---|
| 944 | ! |
|---|
| 945 | !-- Pure passive transport (without particle inertia) |
|---|
| 946 | particles(n)%x = xv(n) + u_int(n) * dt_particle(n) |
|---|
| 947 | particles(n)%y = yv(n) + v_int(n) * dt_particle(n) |
|---|
| 948 | particles(n)%z = zv(n) + w_int(n) * dt_particle(n) |
|---|
| 949 | |
|---|
| 950 | particles(n)%speed_x = u_int(n) |
|---|
| 951 | particles(n)%speed_y = v_int(n) |
|---|
| 952 | particles(n)%speed_z = w_int(n) |
|---|
| 953 | |
|---|
| 954 | ELSE |
|---|
| 955 | ! |
|---|
| 956 | !-- Transport of particles with inertia |
|---|
| 957 | particles(n)%x = particles(n)%x + particles(n)%speed_x * & |
|---|
| 958 | dt_particle(n) |
|---|
| 959 | particles(n)%y = particles(n)%y + particles(n)%speed_y * & |
|---|
| 960 | dt_particle(n) |
|---|
| 961 | particles(n)%z = particles(n)%z + particles(n)%speed_z * & |
|---|
| 962 | dt_particle(n) |
|---|
| 963 | |
|---|
| 964 | ! |
|---|
| 965 | !-- Update of the particle velocity |
|---|
| 966 | IF ( cloud_droplets ) THEN |
|---|
| 967 | ! |
|---|
| 968 | !-- Terminal velocity is computed for vertical direction (Rogers et |
|---|
| 969 | !-- al., 1993, J. Appl. Meteorol.) |
|---|
| 970 | diameter = particles(n)%radius * 2000.0_wp !diameter in mm |
|---|
| 971 | IF ( diameter <= d0_rog ) THEN |
|---|
| 972 | w_s = k_cap_rog * diameter * ( 1.0_wp - EXP( -k_low_rog * diameter ) ) |
|---|
| 973 | ELSE |
|---|
| 974 | w_s = a_rog - b_rog * EXP( -c_rog * diameter ) |
|---|
| 975 | ENDIF |
|---|
| 976 | |
|---|
| 977 | ! |
|---|
| 978 | !-- If selected, add random velocities following Soelch and Kaercher |
|---|
| 979 | !-- (2010, Q. J. R. Meteorol. Soc.) |
|---|
| 980 | IF ( use_sgs_for_particles ) THEN |
|---|
| 981 | lagr_timescale(n) = km(kp,jp,ip) / MAX( e(kp,jp,ip), 1.0E-20_wp ) |
|---|
| 982 | RL = EXP( -1.0_wp * dt_3d / MAX( lagr_timescale(n), & |
|---|
| 983 | 1.0E-20_wp ) ) |
|---|
| 984 | sigma = SQRT( e(kp,jp,ip) ) |
|---|
| 985 | |
|---|
| 986 | rg1 = random_gauss( iran_part, 5.0_wp ) - 1.0_wp |
|---|
| 987 | rg2 = random_gauss( iran_part, 5.0_wp ) - 1.0_wp |
|---|
| 988 | rg3 = random_gauss( iran_part, 5.0_wp ) - 1.0_wp |
|---|
| 989 | |
|---|
| 990 | particles(n)%rvar1 = RL * particles(n)%rvar1 + & |
|---|
| 991 | SQRT( 1.0_wp - RL**2 ) * sigma * rg1 |
|---|
| 992 | particles(n)%rvar2 = RL * particles(n)%rvar2 + & |
|---|
| 993 | SQRT( 1.0_wp - RL**2 ) * sigma * rg2 |
|---|
| 994 | particles(n)%rvar3 = RL * particles(n)%rvar3 + & |
|---|
| 995 | SQRT( 1.0_wp - RL**2 ) * sigma * rg3 |
|---|
| 996 | |
|---|
| 997 | particles(n)%speed_x = u_int(n) + particles(n)%rvar1 |
|---|
| 998 | particles(n)%speed_y = v_int(n) + particles(n)%rvar2 |
|---|
| 999 | particles(n)%speed_z = w_int(n) + particles(n)%rvar3 - w_s |
|---|
| 1000 | ELSE |
|---|
| 1001 | particles(n)%speed_x = u_int(n) |
|---|
| 1002 | particles(n)%speed_y = v_int(n) |
|---|
| 1003 | particles(n)%speed_z = w_int(n) - w_s |
|---|
| 1004 | ENDIF |
|---|
| 1005 | |
|---|
| 1006 | ELSE |
|---|
| 1007 | |
|---|
| 1008 | IF ( use_sgs_for_particles ) THEN |
|---|
| 1009 | exp_arg = particle_groups(particles(n)%group)%exp_arg |
|---|
| 1010 | exp_term = EXP( -exp_arg * dt_particle(n) ) |
|---|
| 1011 | ELSE |
|---|
| 1012 | exp_arg = particle_groups(particles(n)%group)%exp_arg |
|---|
| 1013 | exp_term = particle_groups(particles(n)%group)%exp_term |
|---|
| 1014 | ENDIF |
|---|
| 1015 | particles(n)%speed_x = particles(n)%speed_x * exp_term + & |
|---|
| 1016 | u_int(n) * ( 1.0_wp - exp_term ) |
|---|
| 1017 | particles(n)%speed_y = particles(n)%speed_y * exp_term + & |
|---|
| 1018 | v_int(n) * ( 1.0_wp - exp_term ) |
|---|
| 1019 | particles(n)%speed_z = particles(n)%speed_z * exp_term + & |
|---|
| 1020 | ( w_int(n) - ( 1.0_wp - dens_ratio(n) ) * & |
|---|
| 1021 | g / exp_arg ) * ( 1.0_wp - exp_term ) |
|---|
| 1022 | ENDIF |
|---|
| 1023 | |
|---|
| 1024 | ENDIF |
|---|
| 1025 | ENDDO |
|---|
| 1026 | ENDDO |
|---|
| 1027 | |
|---|
| 1028 | ELSE |
|---|
| 1029 | |
|---|
| 1030 | DO nb = 0, 7 |
|---|
| 1031 | DO n = start_index(nb), end_index(nb) |
|---|
| 1032 | ! |
|---|
| 1033 | !-- Transport of particles with inertia |
|---|
| 1034 | particles(n)%x = xv(n) + particles(n)%speed_x * dt_particle(n) |
|---|
| 1035 | particles(n)%y = yv(n) + particles(n)%speed_y * dt_particle(n) |
|---|
| 1036 | particles(n)%z = zv(n) + particles(n)%speed_z * dt_particle(n) |
|---|
| 1037 | ! |
|---|
| 1038 | !-- Update of the particle velocity |
|---|
| 1039 | IF ( cloud_droplets ) THEN |
|---|
| 1040 | ! |
|---|
| 1041 | !-- Terminal velocity is computed for vertical direction (Rogers et al., |
|---|
| 1042 | !-- 1993, J. Appl. Meteorol.) |
|---|
| 1043 | diameter = particles(n)%radius * 2000.0_wp !diameter in mm |
|---|
| 1044 | IF ( diameter <= d0_rog ) THEN |
|---|
| 1045 | w_s = k_cap_rog * diameter * ( 1.0_wp - EXP( -k_low_rog * diameter ) ) |
|---|
| 1046 | ELSE |
|---|
| 1047 | w_s = a_rog - b_rog * EXP( -c_rog * diameter ) |
|---|
| 1048 | ENDIF |
|---|
| 1049 | |
|---|
| 1050 | ! |
|---|
| 1051 | !-- If selected, add random velocities following Soelch and Kaercher |
|---|
| 1052 | !-- (2010, Q. J. R. Meteorol. Soc.) |
|---|
| 1053 | IF ( use_sgs_for_particles ) THEN |
|---|
| 1054 | lagr_timescale(n) = km(kp,jp,ip) / MAX( e(kp,jp,ip), 1.0E-20_wp ) |
|---|
| 1055 | RL = EXP( -1.0_wp * dt_3d / MAX( lagr_timescale(n), & |
|---|
| 1056 | 1.0E-20_wp ) ) |
|---|
| 1057 | sigma = SQRT( e(kp,jp,ip) ) |
|---|
| 1058 | |
|---|
| 1059 | rg1 = random_gauss( iran_part, 5.0_wp ) - 1.0_wp |
|---|
| 1060 | rg2 = random_gauss( iran_part, 5.0_wp ) - 1.0_wp |
|---|
| 1061 | rg3 = random_gauss( iran_part, 5.0_wp ) - 1.0_wp |
|---|
| 1062 | |
|---|
| 1063 | particles(n)%rvar1 = RL * particles(n)%rvar1 + & |
|---|
| 1064 | SQRT( 1.0_wp - RL**2 ) * sigma * rg1 |
|---|
| 1065 | particles(n)%rvar2 = RL * particles(n)%rvar2 + & |
|---|
| 1066 | SQRT( 1.0_wp - RL**2 ) * sigma * rg2 |
|---|
| 1067 | particles(n)%rvar3 = RL * particles(n)%rvar3 + & |
|---|
| 1068 | SQRT( 1.0_wp - RL**2 ) * sigma * rg3 |
|---|
| 1069 | |
|---|
| 1070 | particles(n)%speed_x = u_int(n) + particles(n)%rvar1 |
|---|
| 1071 | particles(n)%speed_y = v_int(n) + particles(n)%rvar2 |
|---|
| 1072 | particles(n)%speed_z = w_int(n) + particles(n)%rvar3 - w_s |
|---|
| 1073 | ELSE |
|---|
| 1074 | particles(n)%speed_x = u_int(n) |
|---|
| 1075 | particles(n)%speed_y = v_int(n) |
|---|
| 1076 | particles(n)%speed_z = w_int(n) - w_s |
|---|
| 1077 | ENDIF |
|---|
| 1078 | |
|---|
| 1079 | ELSE |
|---|
| 1080 | |
|---|
| 1081 | IF ( use_sgs_for_particles ) THEN |
|---|
| 1082 | exp_arg = particle_groups(particles(n)%group)%exp_arg |
|---|
| 1083 | exp_term = EXP( -exp_arg * dt_particle(n) ) |
|---|
| 1084 | ELSE |
|---|
| 1085 | exp_arg = particle_groups(particles(n)%group)%exp_arg |
|---|
| 1086 | exp_term = particle_groups(particles(n)%group)%exp_term |
|---|
| 1087 | ENDIF |
|---|
| 1088 | particles(n)%speed_x = particles(n)%speed_x * exp_term + & |
|---|
| 1089 | u_int(n) * ( 1.0_wp - exp_term ) |
|---|
| 1090 | particles(n)%speed_y = particles(n)%speed_y * exp_term + & |
|---|
| 1091 | v_int(n) * ( 1.0_wp - exp_term ) |
|---|
| 1092 | particles(n)%speed_z = particles(n)%speed_z * exp_term + & |
|---|
| 1093 | ( w_int(n) - ( 1.0_wp - dens_ratio(n) ) * g / & |
|---|
| 1094 | exp_arg ) * ( 1.0_wp - exp_term ) |
|---|
| 1095 | ENDIF |
|---|
| 1096 | ENDDO |
|---|
| 1097 | ENDDO |
|---|
| 1098 | |
|---|
| 1099 | ENDIF |
|---|
| 1100 | |
|---|
| 1101 | ! |
|---|
| 1102 | !-- Store the old age of the particle ( needed to prevent that a |
|---|
| 1103 | !-- particle crosses several PEs during one timestep, and for the |
|---|
| 1104 | !-- evaluation of the subgrid particle velocity fluctuations ) |
|---|
| 1105 | particles(1:number_of_particles)%age_m = particles(1:number_of_particles)%age |
|---|
| 1106 | |
|---|
| 1107 | DO nb = 0, 7 |
|---|
| 1108 | DO n = start_index(nb), end_index(nb) |
|---|
| 1109 | ! |
|---|
| 1110 | !-- Increment the particle age and the total time that the particle |
|---|
| 1111 | !-- has advanced within the particle timestep procedure |
|---|
| 1112 | particles(n)%age = particles(n)%age + dt_particle(n) |
|---|
| 1113 | particles(n)%dt_sum = particles(n)%dt_sum + dt_particle(n) |
|---|
| 1114 | |
|---|
| 1115 | ! |
|---|
| 1116 | !-- Check whether there is still a particle that has not yet completed |
|---|
| 1117 | !-- the total LES timestep |
|---|
| 1118 | IF ( ( dt_3d - particles(n)%dt_sum ) > 1E-8_wp ) THEN |
|---|
| 1119 | dt_3d_reached_l = .FALSE. |
|---|
| 1120 | ENDIF |
|---|
| 1121 | |
|---|
| 1122 | ENDDO |
|---|
| 1123 | ENDDO |
|---|
| 1124 | |
|---|
| 1125 | CALL cpu_log( log_point_s(44), 'lpm_advec', 'pause' ) |
|---|
| 1126 | |
|---|
| 1127 | |
|---|
| 1128 | END SUBROUTINE lpm_advec |
|---|
| 1129 | |
|---|
| 1130 | ! Description: |
|---|
| 1131 | ! ------------ |
|---|
| 1132 | !> Calculation of subgrid-scale particle speed using the stochastic model |
|---|
| 1133 | !> of Weil et al. (2004, JAS, 61, 2877-2887). |
|---|
| 1134 | !------------------------------------------------------------------------------! |
|---|
| 1135 | SUBROUTINE weil_stochastic_eq( v_sgs, fs_n, e_n, dedxi_n, dedt_n, diss_n, & |
|---|
| 1136 | dt_n, rg_n, fac ) |
|---|
| 1137 | |
|---|
| 1138 | USE kinds |
|---|
| 1139 | |
|---|
| 1140 | USE particle_attributes, & |
|---|
| 1141 | ONLY: c_0, sgs_wf_part |
|---|
| 1142 | |
|---|
| 1143 | IMPLICIT NONE |
|---|
| 1144 | |
|---|
| 1145 | REAL(wp) :: a1 !< dummy argument |
|---|
| 1146 | REAL(wp) :: dedt_n !< time derivative of TKE at particle position |
|---|
| 1147 | REAL(wp) :: dedxi_n !< horizontal derivative of TKE at particle position |
|---|
| 1148 | REAL(wp) :: diss_n !< dissipation at particle position |
|---|
| 1149 | REAL(wp) :: dt_n !< particle timestep |
|---|
| 1150 | REAL(wp) :: e_n !< TKE at particle position |
|---|
| 1151 | REAL(wp) :: fac !< flag to identify adjacent topography |
|---|
| 1152 | REAL(wp) :: fs_n !< weighting factor to prevent that subgrid-scale particle speed becomes too large |
|---|
| 1153 | REAL(wp) :: rg_n !< random number |
|---|
| 1154 | REAL(wp) :: term1 !< memory term |
|---|
| 1155 | REAL(wp) :: term2 !< drift correction term |
|---|
| 1156 | REAL(wp) :: term3 !< random term |
|---|
| 1157 | REAL(wp) :: v_sgs !< subgrid-scale velocity component |
|---|
| 1158 | |
|---|
| 1159 | !-- At first, limit TKE to a small non-zero number, in order to prevent |
|---|
| 1160 | !-- the occurrence of extremely large SGS-velocities in case TKE is zero, |
|---|
| 1161 | !-- (could occur at the simulation begin). |
|---|
| 1162 | e_n = MAX( e_n, 1E-20_wp ) |
|---|
| 1163 | ! |
|---|
| 1164 | !-- Please note, terms 1 and 2 (drift and memory term, respectively) are |
|---|
| 1165 | !-- multiplied by a flag to switch of both terms near topography. |
|---|
| 1166 | !-- This is necessary, as both terms may cause a subgrid-scale velocity build up |
|---|
| 1167 | !-- if particles are trapped in regions with very small TKE, e.g. in narrow street |
|---|
| 1168 | !-- canyons resolved by only a few grid points. Hence, term 1 and term 2 are |
|---|
| 1169 | !-- disabled if one of the adjacent grid points belongs to topography. |
|---|
| 1170 | !-- Moreover, in this case, the previous subgrid-scale component is also set |
|---|
| 1171 | !-- to zero. |
|---|
| 1172 | |
|---|
| 1173 | a1 = fs_n * c_0 * diss_n |
|---|
| 1174 | ! |
|---|
| 1175 | !-- Memory term |
|---|
| 1176 | term1 = - a1 * v_sgs * dt_n / ( 4.0_wp * sgs_wf_part * e_n + 1E-20_wp ) & |
|---|
| 1177 | * fac |
|---|
| 1178 | ! |
|---|
| 1179 | !-- Drift correction term |
|---|
| 1180 | term2 = ( ( dedt_n * v_sgs / e_n ) + dedxi_n ) * 0.5_wp * dt_n & |
|---|
| 1181 | * fac |
|---|
| 1182 | ! |
|---|
| 1183 | !-- Random term |
|---|
| 1184 | term3 = SQRT( MAX( a1, 1E-20_wp ) ) * ( rg_n - 1.0_wp ) * SQRT( dt_n ) |
|---|
| 1185 | ! |
|---|
| 1186 | !-- In cese one of the adjacent grid-boxes belongs to topograhy, the previous |
|---|
| 1187 | !-- subgrid-scale velocity component is set to zero, in order to prevent a |
|---|
| 1188 | !-- velocity build-up. |
|---|
| 1189 | !-- This case, set also previous subgrid-scale component to zero. |
|---|
| 1190 | v_sgs = v_sgs * fac + term1 + term2 + term3 |
|---|
| 1191 | |
|---|
| 1192 | END SUBROUTINE weil_stochastic_eq |
|---|
