| 1 | !> @file lpm_droplet_collision.f90 |
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| 2 | !--------------------------------------------------------------------------------! |
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| 3 | ! This file is part of PALM. |
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| 4 | ! |
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| 5 | ! PALM is free software: you can redistribute it and/or modify it under the terms |
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| 6 | ! of the GNU General Public License as published by the Free Software Foundation, |
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| 7 | ! either version 3 of the License, or (at your option) any later version. |
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| 8 | ! |
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| 9 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY |
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| 10 | ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
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| 11 | ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
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| 12 | ! |
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| 13 | ! You should have received a copy of the GNU General Public License along with |
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| 14 | ! PALM. If not, see <http://www.gnu.org/licenses/>. |
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| 15 | ! |
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| 16 | ! Copyright 1997-2014 Leibniz Universitaet Hannover |
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| 17 | !--------------------------------------------------------------------------------! |
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| 18 | ! |
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| 19 | ! Current revisions: |
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| 20 | ! ------------------ |
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| 21 | ! |
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| 22 | ! |
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| 23 | ! Former revisions: |
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| 24 | ! ----------------- |
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| 25 | ! $Id: lpm_droplet_collision.f90 1683 2015-10-07 23:57:51Z knoop $ |
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| 26 | ! |
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| 27 | ! 1682 2015-10-07 23:56:08Z knoop |
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| 28 | ! Code annotations made doxygen readable |
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| 29 | ! |
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| 30 | ! 1359 2014-04-11 17:15:14Z hoffmann |
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| 31 | ! New particle structure integrated. |
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| 32 | ! Kind definition added to all floating point numbers. |
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| 33 | ! |
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| 34 | ! 1322 2014-03-20 16:38:49Z raasch |
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| 35 | ! REAL constants defined as wp_kind |
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| 36 | ! |
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| 37 | ! 1320 2014-03-20 08:40:49Z raasch |
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| 38 | ! ONLY-attribute added to USE-statements, |
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| 39 | ! kind-parameters added to all INTEGER and REAL declaration statements, |
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| 40 | ! kinds are defined in new module kinds, |
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| 41 | ! revision history before 2012 removed, |
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| 42 | ! comment fields (!:) to be used for variable explanations added to |
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| 43 | ! all variable declaration statements |
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| 44 | ! |
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| 45 | ! 1092 2013-02-02 11:24:22Z raasch |
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| 46 | ! unused variables removed |
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| 47 | ! |
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| 48 | ! 1071 2012-11-29 16:54:55Z franke |
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| 49 | ! Calculation of Hall and Wang kernel now uses collision-coalescence formulation |
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| 50 | ! proposed by Wang instead of the continuous collection equation (for more |
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| 51 | ! information about new method see PALM documentation) |
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| 52 | ! Bugfix: message identifiers added |
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| 53 | ! |
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| 54 | ! 1036 2012-10-22 13:43:42Z raasch |
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| 55 | ! code put under GPL (PALM 3.9) |
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| 56 | ! |
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| 57 | ! 849 2012-03-15 10:35:09Z raasch |
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| 58 | ! initial revision (former part of advec_particles) |
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| 59 | ! |
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| 60 | ! |
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| 61 | ! Description: |
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| 62 | ! ------------ |
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| 63 | !> Calculates change in droplet radius by collision. Droplet collision is |
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| 64 | !> calculated for each grid box seperately. Collision is parameterized by |
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| 65 | !> using collision kernels. Three different kernels are available: |
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| 66 | !> PALM kernel: Kernel is approximated using a method from Rogers and |
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| 67 | !> Yau (1989, A Short Course in Cloud Physics, Pergamon Press). |
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| 68 | !> All droplets smaller than the treated one are represented by |
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| 69 | !> one droplet with mean features. Collision efficiencies are taken |
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| 70 | !> from the respective table in Rogers and Yau. |
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| 71 | !> Hall kernel: Kernel from Hall (1980, J. Atmos. Sci., 2486-2507), which |
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| 72 | !> considers collision due to pure gravitational effects. |
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| 73 | !> Wang kernel: Beside gravitational effects (treated with the Hall-kernel) also |
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| 74 | !> the effects of turbulence on the collision are considered using |
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| 75 | !> parameterizations of Ayala et al. (2008, New J. Phys., 10, |
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| 76 | !> 075015) and Wang and Grabowski (2009, Atmos. Sci. Lett., 10, |
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| 77 | !> 1-8). This kernel includes three possible effects of turbulence: |
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| 78 | !> the modification of the relative velocity between the droplets, |
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| 79 | !> the effect of preferential concentration, and the enhancement of |
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| 80 | !> collision efficiencies. |
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| 81 | !------------------------------------------------------------------------------! |
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| 82 | SUBROUTINE lpm_droplet_collision (i,j,k) |
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| 83 | |
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| 84 | |
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| 85 | |
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| 86 | USE arrays_3d, & |
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| 87 | ONLY: diss, ql, ql_v, ql_vp, u, v, w, zu, zw |
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| 88 | |
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| 89 | USE cloud_parameters, & |
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| 90 | ONLY: effective_coll_efficiency |
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| 91 | |
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| 92 | USE constants, & |
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| 93 | ONLY: pi |
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| 94 | |
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| 95 | USE control_parameters, & |
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| 96 | ONLY: dt_3d, message_string, u_gtrans, v_gtrans, dz |
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| 97 | |
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| 98 | USE cpulog, & |
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| 99 | ONLY: cpu_log, log_point_s |
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| 100 | |
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| 101 | USE grid_variables, & |
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| 102 | ONLY: ddx, dx, ddy, dy |
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| 103 | |
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| 104 | USE indices, & |
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| 105 | ONLY: nxl, nxr, nyn, nys, nzb, nzt |
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| 106 | |
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| 107 | USE kinds |
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| 108 | |
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| 109 | USE lpm_collision_kernels_mod, & |
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| 110 | ONLY: ckernel, collision_efficiency_rogers, recalculate_kernel |
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| 111 | |
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| 112 | USE particle_attributes, & |
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| 113 | ONLY: deleted_particles, dissipation_classes, hall_kernel, & |
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| 114 | palm_kernel, particles, particle_type, & |
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| 115 | prt_count, use_kernel_tables, wang_kernel |
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| 116 | |
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| 117 | USE pegrid |
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| 118 | |
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| 119 | IMPLICIT NONE |
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| 120 | |
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| 121 | INTEGER(iwp) :: eclass !< |
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| 122 | INTEGER(iwp) :: i !< |
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| 123 | INTEGER(iwp) :: ii !< |
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| 124 | INTEGER(iwp) :: inc !< |
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| 125 | INTEGER(iwp) :: is !< |
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| 126 | INTEGER(iwp) :: j !< |
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| 127 | INTEGER(iwp) :: jj !< |
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| 128 | INTEGER(iwp) :: js !< |
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| 129 | INTEGER(iwp) :: k !< |
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| 130 | INTEGER(iwp) :: kk !< |
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| 131 | INTEGER(iwp) :: n !< |
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| 132 | INTEGER(iwp) :: pse !< |
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| 133 | INTEGER(iwp) :: psi !< |
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| 134 | INTEGER(iwp) :: rclass_l !< |
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| 135 | INTEGER(iwp) :: rclass_s !< |
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| 136 | |
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| 137 | INTEGER(iwp), DIMENSION(prt_count(k,j,i)) :: rclass_v !< |
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| 138 | |
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| 139 | LOGICAL, SAVE :: first_flag = .TRUE. !< |
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| 140 | |
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| 141 | TYPE(particle_type) :: tmp_particle !< |
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| 142 | |
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| 143 | REAL(wp) :: aa !< |
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| 144 | REAL(wp) :: auxn !< temporary variables |
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| 145 | REAL(wp) :: auxs !< temporary variables |
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| 146 | REAL(wp) :: bb !< |
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| 147 | REAL(wp) :: cc !< |
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| 148 | REAL(wp) :: dd !< |
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| 149 | REAL(wp) :: ddV !< |
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| 150 | REAL(wp) :: delta_r !< |
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| 151 | REAL(wp) :: delta_v !< |
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| 152 | REAL(wp) :: epsilon !< |
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| 153 | REAL(wp) :: gg !< |
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| 154 | REAL(wp) :: mean_r !< |
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| 155 | REAL(wp) :: ql_int !< |
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| 156 | REAL(wp) :: ql_int_l !< |
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| 157 | REAL(wp) :: ql_int_u !< |
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| 158 | REAL(wp) :: r3 !< |
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| 159 | REAL(wp) :: sl_r3 !< |
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| 160 | REAL(wp) :: sl_r4 !< |
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| 161 | REAL(wp) :: sum1 !< |
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| 162 | REAL(wp) :: sum2 !< |
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| 163 | REAL(wp) :: sum3 !< |
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| 164 | REAL(wp) :: u_int !< |
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| 165 | REAL(wp) :: u_int_l !< |
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| 166 | REAL(wp) :: u_int_u !< |
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| 167 | REAL(wp) :: v_int !< |
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| 168 | REAL(wp) :: v_int_l !< |
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| 169 | REAL(wp) :: v_int_u !< |
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| 170 | REAL(wp) :: w_int !< |
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| 171 | REAL(wp) :: w_int_l !< |
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| 172 | REAL(wp) :: w_int_u !< |
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| 173 | REAL(wp) :: x !< |
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| 174 | REAL(wp) :: y !< |
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| 175 | |
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| 176 | REAL(wp), DIMENSION(:), ALLOCATABLE :: rad !< |
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| 177 | REAL(wp), DIMENSION(:), ALLOCATABLE :: weight !< |
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| 178 | |
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| 179 | REAL, DIMENSION(prt_count(k,j,i)) :: ck |
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| 180 | REAL, DIMENSION(prt_count(k,j,i)) :: r3v |
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| 181 | REAL, DIMENSION(prt_count(k,j,i)) :: sum1v |
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| 182 | REAL, DIMENSION(prt_count(k,j,i)) :: sum2v |
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| 183 | |
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| 184 | CALL cpu_log( log_point_s(43), 'lpm_droplet_coll', 'start' ) |
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| 185 | |
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| 186 | ! |
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| 187 | !-- Collision requires at least two particles in the box |
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| 188 | IF ( prt_count(k,j,i) > 1 ) THEN |
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| 189 | ! |
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| 190 | !-- First, sort particles within the gridbox by their size, |
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| 191 | !-- using Shell's method (see Numerical Recipes) |
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| 192 | !-- NOTE: In case of using particle tails, the re-sorting of |
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| 193 | !-- ---- tails would have to be included here! |
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| 194 | IF ( .NOT. ( ( hall_kernel .OR. wang_kernel ) .AND. & |
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| 195 | use_kernel_tables ) ) THEN |
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| 196 | psi = 0 |
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| 197 | inc = 1 |
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| 198 | DO WHILE ( inc <= prt_count(k,j,i) ) |
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| 199 | inc = 3 * inc + 1 |
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| 200 | ENDDO |
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| 201 | |
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| 202 | DO WHILE ( inc > 1 ) |
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| 203 | inc = inc / 3 |
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| 204 | DO is = inc+1, prt_count(k,j,i) |
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| 205 | tmp_particle = particles(psi+is) |
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| 206 | js = is |
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| 207 | DO WHILE ( particles(psi+js-inc)%radius > & |
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| 208 | tmp_particle%radius ) |
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| 209 | particles(psi+js) = particles(psi+js-inc) |
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| 210 | js = js - inc |
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| 211 | IF ( js <= inc ) EXIT |
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| 212 | ENDDO |
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| 213 | particles(psi+js) = tmp_particle |
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| 214 | ENDDO |
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| 215 | ENDDO |
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| 216 | ENDIF |
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| 217 | |
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| 218 | psi = 1 |
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| 219 | pse = prt_count(k,j,i) |
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| 220 | |
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| 221 | ! |
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| 222 | !-- Now apply the different kernels |
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| 223 | IF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
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| 224 | use_kernel_tables ) THEN |
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| 225 | ! |
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| 226 | !-- Fast method with pre-calculated efficiencies for |
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| 227 | !-- discrete radius- and dissipation-classes. |
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| 228 | !-- |
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| 229 | !-- Determine dissipation class index of this gridbox |
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| 230 | IF ( wang_kernel ) THEN |
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| 231 | eclass = INT( diss(k,j,i) * 1.0E4_wp / 1000.0_wp * & |
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| 232 | dissipation_classes ) + 1 |
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| 233 | epsilon = diss(k,j,i) |
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| 234 | ELSE |
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| 235 | epsilon = 0.0_wp |
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| 236 | ENDIF |
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| 237 | IF ( hall_kernel .OR. epsilon * 1.0E4_wp < 0.001_wp ) THEN |
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| 238 | eclass = 0 ! Hall kernel is used |
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| 239 | ELSE |
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| 240 | eclass = MIN( dissipation_classes, eclass ) |
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| 241 | ENDIF |
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| 242 | |
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| 243 | ! |
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| 244 | !-- Droplet collision are calculated using collision-coalescence |
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| 245 | !-- formulation proposed by Wang (see PALM documentation) |
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| 246 | !-- Since new radii after collision are defined by radii of all |
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| 247 | !-- droplets before collision, temporary fields for new radii and |
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| 248 | !-- weighting factors are needed |
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| 249 | ALLOCATE(rad(1:prt_count(k,j,i)), weight(1:prt_count(k,j,i))) |
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| 250 | |
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| 251 | rad = 0.0_wp |
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| 252 | weight = 0.0_wp |
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| 253 | |
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| 254 | sum1v(1:prt_count(k,j,i)) = 0.0_wp |
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| 255 | sum2v(1:prt_count(k,j,i)) = 0.0_wp |
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| 256 | |
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| 257 | DO n = 1, prt_count(k,j,i) |
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| 258 | |
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| 259 | rclass_l = particles(n)%class |
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| 260 | ! |
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| 261 | !-- Mass added due to collisions with smaller droplets |
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| 262 | DO is = n+1, prt_count(k,j,i) |
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| 263 | rclass_s = particles(is)%class |
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| 264 | auxs = ckernel(rclass_l,rclass_s,eclass) * particles(is)%weight_factor |
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| 265 | auxn = ckernel(rclass_s,rclass_l,eclass) * particles(n)%weight_factor |
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| 266 | IF ( particles(is)%radius < particles(n)%radius ) THEN |
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| 267 | sum1v(n) = sum1v(n) + particles(is)%radius**3 * auxs |
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| 268 | sum2v(is) = sum2v(is) + auxn |
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| 269 | ELSE |
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| 270 | sum2v(n) = sum2v(n) + auxs |
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| 271 | sum1v(is) = sum1v(is) + particles(n)%radius**3 * auxn |
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| 272 | ENDIF |
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| 273 | ENDDO |
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| 274 | ENDDO |
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| 275 | rclass_v = particles(1:prt_count(k,j,i))%class |
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| 276 | DO n = 1, prt_count(k,j,i) |
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| 277 | ck(n) = ckernel(rclass_v(n),rclass_v(n),eclass) |
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| 278 | ENDDO |
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| 279 | r3v = particles(1:prt_count(k,j,i))%radius**3 |
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| 280 | DO n = 1, prt_count(k,j,i) |
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| 281 | sum3 = 0.0_wp |
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| 282 | ddV = ddx * ddy / dz |
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| 283 | ! |
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| 284 | !-- Change of the current weighting factor |
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| 285 | sum3 = 1 - dt_3d * ddV * & |
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| 286 | ck(n) * & |
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| 287 | ( particles(n)%weight_factor - 1 ) * 0.5_wp - & |
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| 288 | dt_3d * ddV * sum2v(n) |
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| 289 | weight(n) = particles(n)%weight_factor * sum3 |
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| 290 | ! |
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| 291 | !-- Change of the current droplet radius |
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| 292 | rad(n) = ( (r3v(n) + dt_3d * ddV * (sum1v(n) - sum2v(n) * r3v(n)) )/& |
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| 293 | sum3 )**0.33333333333333_wp |
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| 294 | |
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| 295 | ql_vp(k,j,i) = ql_vp(k,j,i) + weight(n) & |
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| 296 | * rad(n)**3 |
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| 297 | |
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| 298 | ENDDO |
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| 299 | IF ( ANY(weight < 0.0_wp) ) THEN |
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| 300 | WRITE( message_string, * ) 'negative weighting' |
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| 301 | CALL message( 'lpm_droplet_collision', 'PA0028', & |
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| 302 | 2, 2, -1, 6, 1 ) |
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| 303 | ENDIF |
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| 304 | |
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| 305 | particles(psi:pse)%radius = rad(1:prt_count(k,j,i)) |
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| 306 | particles(psi:pse)%weight_factor = weight(1:prt_count(k,j,i)) |
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| 307 | |
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| 308 | DEALLOCATE(rad, weight) |
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| 309 | |
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| 310 | ELSEIF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
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| 311 | .NOT. use_kernel_tables ) THEN |
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| 312 | ! |
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| 313 | !-- Collision efficiencies are calculated for every new |
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| 314 | !-- grid box. First, allocate memory for kernel table. |
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| 315 | !-- Third dimension is 1, because table is re-calculated for |
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| 316 | !-- every new dissipation value. |
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| 317 | ALLOCATE( ckernel(1:prt_count(k,j,i),1:prt_count(k,j,i),1:1) ) |
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| 318 | ! |
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| 319 | !-- Now calculate collision efficiencies for this box |
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| 320 | CALL recalculate_kernel( i, j, k ) |
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| 321 | |
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| 322 | ! |
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| 323 | !-- Droplet collision are calculated using collision-coalescence |
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| 324 | !-- formulation proposed by Wang (see PALM documentation) |
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| 325 | !-- Since new radii after collision are defined by radii of all |
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| 326 | !-- droplets before collision, temporary fields for new radii and |
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| 327 | !-- weighting factors are needed |
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| 328 | ALLOCATE(rad(1:prt_count(k,j,i)), weight(1:prt_count(k,j,i))) |
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| 329 | |
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| 330 | rad = 0.0_wp |
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| 331 | weight = 0.0_wp |
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| 332 | |
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| 333 | DO n = psi, pse, 1 |
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| 334 | |
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| 335 | sum1 = 0.0_wp |
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| 336 | sum2 = 0.0_wp |
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| 337 | sum3 = 0.0_wp |
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| 338 | ! |
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| 339 | !-- Mass added due to collisions with smaller droplets |
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| 340 | DO is = psi, n-1 |
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| 341 | sum1 = sum1 + ( particles(is)%radius**3 * & |
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| 342 | ckernel(n,is,1) * & |
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| 343 | particles(is)%weight_factor ) |
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| 344 | ENDDO |
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| 345 | ! |
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| 346 | !-- Rate of collisions with larger droplets |
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| 347 | DO is = n+1, pse |
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| 348 | sum2 = sum2 + ( ckernel(n,is,1) * & |
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| 349 | particles(is)%weight_factor ) |
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| 350 | ENDDO |
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| 351 | |
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| 352 | r3 = particles(n)%radius**3 |
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| 353 | ddV = ddx * ddy / dz |
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| 354 | is = 1 |
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| 355 | ! |
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| 356 | !-- Change of the current weighting factor |
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| 357 | sum3 = 1 - dt_3d * ddV * & |
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| 358 | ckernel(n,n,1) * & |
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| 359 | ( particles(n)%weight_factor - 1 ) * 0.5_wp - & |
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| 360 | dt_3d * ddV * sum2 |
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| 361 | weight(n-is+1) = particles(n)%weight_factor * sum3 |
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| 362 | ! |
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| 363 | !-- Change of the current droplet radius |
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| 364 | rad(n-is+1) = ( (r3 + dt_3d * ddV * (sum1 - sum2 * r3) )/& |
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| 365 | sum3 )**0.33333333333333_wp |
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| 366 | |
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| 367 | IF ( weight(n-is+1) < 0.0_wp ) THEN |
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| 368 | WRITE( message_string, * ) 'negative weighting', & |
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| 369 | 'factor: ', weight(n-is+1) |
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| 370 | CALL message( 'lpm_droplet_collision', 'PA0037', & |
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| 371 | 2, 2, -1, 6, 1 ) |
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| 372 | ENDIF |
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| 373 | |
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| 374 | ql_vp(k,j,i) = ql_vp(k,j,i) + weight(n-is+1) & |
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| 375 | * rad(n-is+1)**3 |
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| 376 | |
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| 377 | ENDDO |
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| 378 | |
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| 379 | particles(psi:pse)%radius = rad(1:prt_count(k,j,i)) |
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| 380 | particles(psi:pse)%weight_factor = weight(1:prt_count(k,j,i)) |
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| 381 | |
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| 382 | DEALLOCATE( rad, weight, ckernel ) |
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| 383 | |
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| 384 | ELSEIF ( palm_kernel ) THEN |
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| 385 | ! |
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| 386 | !-- PALM collision kernel |
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| 387 | ! |
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| 388 | !-- Calculate the mean radius of all those particles which |
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| 389 | !-- are of smaller size than the current particle and |
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| 390 | !-- use this radius for calculating the collision efficiency |
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| 391 | DO n = psi+prt_count(k,j,i)-1, psi+1, -1 |
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| 392 | |
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| 393 | sl_r3 = 0.0_wp |
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| 394 | sl_r4 = 0.0_wp |
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| 395 | |
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| 396 | DO is = n-1, psi, -1 |
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| 397 | IF ( particles(is)%radius < particles(n)%radius ) & |
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| 398 | THEN |
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| 399 | sl_r3 = sl_r3 + particles(is)%weight_factor & |
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| 400 | * particles(is)%radius**3 |
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| 401 | sl_r4 = sl_r4 + particles(is)%weight_factor & |
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| 402 | * particles(is)%radius**4 |
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| 403 | ENDIF |
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| 404 | ENDDO |
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| 405 | |
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| 406 | IF ( ( sl_r3 ) > 0.0_wp ) THEN |
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| 407 | mean_r = ( sl_r4 ) / ( sl_r3 ) |
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| 408 | |
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| 409 | CALL collision_efficiency_rogers( mean_r, & |
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| 410 | particles(n)%radius, & |
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| 411 | effective_coll_efficiency ) |
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| 412 | |
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| 413 | ELSE |
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| 414 | effective_coll_efficiency = 0.0_wp |
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| 415 | ENDIF |
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| 416 | |
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| 417 | IF ( effective_coll_efficiency > 1.0_wp .OR. & |
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| 418 | effective_coll_efficiency < 0.0_wp ) & |
|---|
| 419 | THEN |
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| 420 | WRITE( message_string, * ) 'collision_efficien' , & |
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| 421 | 'cy out of range:' ,effective_coll_efficiency |
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| 422 | CALL message( 'lpm_droplet_collision', 'PA0145', 2, & |
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| 423 | 2, -1, 6, 1 ) |
|---|
| 424 | ENDIF |
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| 425 | |
|---|
| 426 | ! |
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| 427 | !-- Interpolation of liquid water content |
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| 428 | ii = particles(n)%x * ddx |
|---|
| 429 | jj = particles(n)%y * ddy |
|---|
| 430 | kk = ( particles(n)%z + 0.5_wp * dz ) / dz |
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| 431 | |
|---|
| 432 | x = particles(n)%x - ii * dx |
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| 433 | y = particles(n)%y - jj * dy |
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| 434 | aa = x**2 + y**2 |
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| 435 | bb = ( dx - x )**2 + y**2 |
|---|
| 436 | cc = x**2 + ( dy - y )**2 |
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| 437 | dd = ( dx - x )**2 + ( dy - y )**2 |
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| 438 | gg = aa + bb + cc + dd |
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| 439 | |
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| 440 | ql_int_l = ( (gg-aa) * ql(kk,jj,ii) + (gg-bb) * & |
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| 441 | ql(kk,jj,ii+1) & |
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| 442 | + (gg-cc) * ql(kk,jj+1,ii) + ( gg-dd ) * & |
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| 443 | ql(kk,jj+1,ii+1) & |
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| 444 | ) / ( 3.0_wp * gg ) |
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| 445 | |
|---|
| 446 | ql_int_u = ( (gg-aa) * ql(kk+1,jj,ii) + (gg-bb) * & |
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| 447 | ql(kk+1,jj,ii+1) & |
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| 448 | + (gg-cc) * ql(kk+1,jj+1,ii) + (gg-dd) * & |
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| 449 | ql(kk+1,jj+1,ii+1) & |
|---|
| 450 | ) / ( 3.0_wp * gg ) |
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| 451 | |
|---|
| 452 | ql_int = ql_int_l + ( particles(n)%z - zu(kk) ) / dz *& |
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| 453 | ( ql_int_u - ql_int_l ) |
|---|
| 454 | |
|---|
| 455 | ! |
|---|
| 456 | !-- Interpolate u velocity-component |
|---|
| 457 | ii = ( particles(n)%x + 0.5_wp * dx ) * ddx |
|---|
| 458 | jj = particles(n)%y * ddy |
|---|
| 459 | kk = ( particles(n)%z + 0.5_wp * dz ) / dz ! only if equidistant |
|---|
| 460 | |
|---|
| 461 | IF ( ( particles(n)%z - zu(kk) ) > ( 0.5_wp * dz ) ) kk = kk+1 |
|---|
| 462 | |
|---|
| 463 | x = particles(n)%x + ( 0.5_wp - ii ) * dx |
|---|
| 464 | y = particles(n)%y - jj * dy |
|---|
| 465 | aa = x**2 + y**2 |
|---|
| 466 | bb = ( dx - x )**2 + y**2 |
|---|
| 467 | cc = x**2 + ( dy - y )**2 |
|---|
| 468 | dd = ( dx - x )**2 + ( dy - y )**2 |
|---|
| 469 | gg = aa + bb + cc + dd |
|---|
| 470 | |
|---|
| 471 | u_int_l = ( (gg-aa) * u(kk,jj,ii) + (gg-bb) * & |
|---|
| 472 | u(kk,jj,ii+1) & |
|---|
| 473 | + (gg-cc) * u(kk,jj+1,ii) + (gg-dd) * & |
|---|
| 474 | u(kk,jj+1,ii+1) & |
|---|
| 475 | ) / ( 3.0_wp * gg ) - u_gtrans |
|---|
| 476 | IF ( kk+1 == nzt+1 ) THEN |
|---|
| 477 | u_int = u_int_l |
|---|
| 478 | ELSE |
|---|
| 479 | u_int_u = ( (gg-aa) * u(kk+1,jj,ii) + (gg-bb) * & |
|---|
| 480 | u(kk+1,jj,ii+1) & |
|---|
| 481 | + (gg-cc) * u(kk+1,jj+1,ii) + (gg-dd) * & |
|---|
| 482 | u(kk+1,jj+1,ii+1) & |
|---|
| 483 | ) / ( 3.0_wp * gg ) - u_gtrans |
|---|
| 484 | u_int = u_int_l + ( particles(n)%z - zu(kk) ) / dz & |
|---|
| 485 | * ( u_int_u - u_int_l ) |
|---|
| 486 | ENDIF |
|---|
| 487 | |
|---|
| 488 | ! |
|---|
| 489 | !-- Same procedure for interpolation of the v velocity-component |
|---|
| 490 | !-- (adopt index k from u velocity-component) |
|---|
| 491 | ii = particles(n)%x * ddx |
|---|
| 492 | jj = ( particles(n)%y + 0.5_wp * dy ) * ddy |
|---|
| 493 | |
|---|
| 494 | x = particles(n)%x - ii * dx |
|---|
| 495 | y = particles(n)%y + ( 0.5_wp - jj ) * dy |
|---|
| 496 | aa = x**2 + y**2 |
|---|
| 497 | bb = ( dx - x )**2 + y**2 |
|---|
| 498 | cc = x**2 + ( dy - y )**2 |
|---|
| 499 | dd = ( dx - x )**2 + ( dy - y )**2 |
|---|
| 500 | gg = aa + bb + cc + dd |
|---|
| 501 | |
|---|
| 502 | v_int_l = ( ( gg-aa ) * v(kk,jj,ii) + ( gg-bb ) * & |
|---|
| 503 | v(kk,jj,ii+1) & |
|---|
| 504 | + ( gg-cc ) * v(kk,jj+1,ii) + ( gg-dd ) * & |
|---|
| 505 | v(kk,jj+1,ii+1) & |
|---|
| 506 | ) / ( 3.0_wp * gg ) - v_gtrans |
|---|
| 507 | IF ( kk+1 == nzt+1 ) THEN |
|---|
| 508 | v_int = v_int_l |
|---|
| 509 | ELSE |
|---|
| 510 | v_int_u = ( (gg-aa) * v(kk+1,jj,ii) + (gg-bb) * & |
|---|
| 511 | v(kk+1,jj,ii+1) & |
|---|
| 512 | + (gg-cc) * v(kk+1,jj+1,ii) + (gg-dd) * & |
|---|
| 513 | v(kk+1,jj+1,ii+1) & |
|---|
| 514 | ) / ( 3.0_wp * gg ) - v_gtrans |
|---|
| 515 | v_int = v_int_l + ( particles(n)%z - zu(kk) ) / dz & |
|---|
| 516 | * ( v_int_u - v_int_l ) |
|---|
| 517 | ENDIF |
|---|
| 518 | |
|---|
| 519 | ! |
|---|
| 520 | !-- Same procedure for interpolation of the w velocity-component |
|---|
| 521 | !-- (adopt index i from v velocity-component) |
|---|
| 522 | jj = particles(n)%y * ddy |
|---|
| 523 | kk = particles(n)%z / dz |
|---|
| 524 | |
|---|
| 525 | x = particles(n)%x - ii * dx |
|---|
| 526 | y = particles(n)%y - jj * dy |
|---|
| 527 | aa = x**2 + y**2 |
|---|
| 528 | bb = ( dx - x )**2 + y**2 |
|---|
| 529 | cc = x**2 + ( dy - y )**2 |
|---|
| 530 | dd = ( dx - x )**2 + ( dy - y )**2 |
|---|
| 531 | gg = aa + bb + cc + dd |
|---|
| 532 | |
|---|
| 533 | w_int_l = ( ( gg-aa ) * w(kk,jj,ii) + ( gg-bb ) * & |
|---|
| 534 | w(kk,jj,ii+1) & |
|---|
| 535 | + ( gg-cc ) * w(kk,jj+1,ii) + ( gg-dd ) * & |
|---|
| 536 | w(kk,jj+1,ii+1) & |
|---|
| 537 | ) / ( 3.0_wp * gg ) |
|---|
| 538 | IF ( kk+1 == nzt+1 ) THEN |
|---|
| 539 | w_int = w_int_l |
|---|
| 540 | ELSE |
|---|
| 541 | w_int_u = ( (gg-aa) * w(kk+1,jj,ii) + (gg-bb) * & |
|---|
| 542 | w(kk+1,jj,ii+1) & |
|---|
| 543 | + (gg-cc) * w(kk+1,jj+1,ii) + (gg-dd) * & |
|---|
| 544 | w(kk+1,jj+1,ii+1) & |
|---|
| 545 | ) / ( 3.0_wp * gg ) |
|---|
| 546 | w_int = w_int_l + ( particles(n)%z - zw(kk) ) / dz & |
|---|
| 547 | * ( w_int_u - w_int_l ) |
|---|
| 548 | ENDIF |
|---|
| 549 | |
|---|
| 550 | ! |
|---|
| 551 | !-- Change in radius due to collision |
|---|
| 552 | delta_r = effective_coll_efficiency / 3.0_wp & |
|---|
| 553 | * pi * sl_r3 * ddx * ddy / dz & |
|---|
| 554 | * SQRT( ( u_int - particles(n)%speed_x )**2 & |
|---|
| 555 | + ( v_int - particles(n)%speed_y )**2 & |
|---|
| 556 | + ( w_int - particles(n)%speed_z )**2 & |
|---|
| 557 | ) * dt_3d |
|---|
| 558 | ! |
|---|
| 559 | !-- Change in volume due to collision |
|---|
| 560 | delta_v = particles(n)%weight_factor & |
|---|
| 561 | * ( ( particles(n)%radius + delta_r )**3 & |
|---|
| 562 | - particles(n)%radius**3 ) |
|---|
| 563 | |
|---|
| 564 | ! |
|---|
| 565 | !-- Check if collected particles provide enough LWC for |
|---|
| 566 | !-- volume change of collector particle |
|---|
| 567 | IF ( delta_v >= sl_r3 .AND. sl_r3 > 0.0_wp ) THEN |
|---|
| 568 | |
|---|
| 569 | delta_r = ( ( sl_r3/particles(n)%weight_factor ) & |
|---|
| 570 | + particles(n)%radius**3 )**( 1.0_wp / 3.0_wp ) & |
|---|
| 571 | - particles(n)%radius |
|---|
| 572 | |
|---|
| 573 | DO is = n-1, psi, -1 |
|---|
| 574 | IF ( particles(is)%radius < particles(n)%radius ) THEN |
|---|
| 575 | particles(is)%weight_factor = 0.0_wp |
|---|
| 576 | particles(is)%particle_mask = .FALSE. |
|---|
| 577 | deleted_particles = deleted_particles + 1 |
|---|
| 578 | ENDIF |
|---|
| 579 | ENDDO |
|---|
| 580 | |
|---|
| 581 | ELSE IF ( delta_v < sl_r3 .AND. sl_r3 > 0.0_wp ) THEN |
|---|
| 582 | |
|---|
| 583 | DO is = n-1, psi, -1 |
|---|
| 584 | IF ( particles(is)%radius < particles(n)%radius & |
|---|
| 585 | .AND. sl_r3 > 0.0_wp ) THEN |
|---|
| 586 | particles(is)%weight_factor = & |
|---|
| 587 | ( ( particles(is)%weight_factor & |
|---|
| 588 | * ( particles(is)%radius**3 ) ) & |
|---|
| 589 | - ( delta_v & |
|---|
| 590 | * particles(is)%weight_factor & |
|---|
| 591 | * ( particles(is)%radius**3 ) & |
|---|
| 592 | / sl_r3 ) ) & |
|---|
| 593 | / ( particles(is)%radius**3 ) |
|---|
| 594 | |
|---|
| 595 | IF ( particles(is)%weight_factor < 0.0_wp ) THEN |
|---|
| 596 | WRITE( message_string, * ) 'negative ', & |
|---|
| 597 | 'weighting factor: ', & |
|---|
| 598 | particles(is)%weight_factor |
|---|
| 599 | CALL message( 'lpm_droplet_collision', & |
|---|
| 600 | 'PA0039', & |
|---|
| 601 | 2, 2, -1, 6, 1 ) |
|---|
| 602 | ENDIF |
|---|
| 603 | ENDIF |
|---|
| 604 | ENDDO |
|---|
| 605 | |
|---|
| 606 | ENDIF |
|---|
| 607 | |
|---|
| 608 | particles(n)%radius = particles(n)%radius + delta_r |
|---|
| 609 | ql_vp(k,j,i) = ql_vp(k,j,i) + & |
|---|
| 610 | particles(n)%weight_factor * & |
|---|
| 611 | ( particles(n)%radius**3 ) |
|---|
| 612 | ENDDO |
|---|
| 613 | |
|---|
| 614 | ql_vp(k,j,i) = ql_vp(k,j,i) + particles(psi)%weight_factor & |
|---|
| 615 | * particles(psi)%radius**3 |
|---|
| 616 | |
|---|
| 617 | ENDIF ! collision kernel |
|---|
| 618 | |
|---|
| 619 | ELSE IF ( prt_count(k,j,i) == 1 ) THEN |
|---|
| 620 | |
|---|
| 621 | psi = 1 |
|---|
| 622 | |
|---|
| 623 | ! |
|---|
| 624 | !-- Calculate change of weighting factor due to self collision |
|---|
| 625 | IF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
|---|
| 626 | use_kernel_tables ) THEN |
|---|
| 627 | |
|---|
| 628 | IF ( wang_kernel ) THEN |
|---|
| 629 | eclass = INT( diss(k,j,i) * 1.0E4_wp / 1000.0_wp * & |
|---|
| 630 | dissipation_classes ) + 1 |
|---|
| 631 | epsilon = diss(k,j,i) |
|---|
| 632 | ELSE |
|---|
| 633 | epsilon = 0.0_wp |
|---|
| 634 | ENDIF |
|---|
| 635 | IF ( hall_kernel .OR. epsilon * 1.0E4_wp < 0.001_wp ) THEN |
|---|
| 636 | eclass = 0 ! Hall kernel is used |
|---|
| 637 | ELSE |
|---|
| 638 | eclass = MIN( dissipation_classes, eclass ) |
|---|
| 639 | ENDIF |
|---|
| 640 | |
|---|
| 641 | ddV = ddx * ddy / dz |
|---|
| 642 | rclass_l = particles(psi)%class |
|---|
| 643 | sum3 = 1 - dt_3d * ddV * & |
|---|
| 644 | ( ckernel(rclass_l,rclass_l,eclass) * & |
|---|
| 645 | ( particles(psi)%weight_factor-1 ) * 0.5_wp ) |
|---|
| 646 | |
|---|
| 647 | particles(psi)%radius = ( particles(psi)%radius**3 / & |
|---|
| 648 | sum3 )**0.33333333333333_wp |
|---|
| 649 | particles(psi)%weight_factor = particles(psi)%weight_factor & |
|---|
| 650 | * sum3 |
|---|
| 651 | |
|---|
| 652 | ELSE IF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
|---|
| 653 | .NOT. use_kernel_tables ) THEN |
|---|
| 654 | ! |
|---|
| 655 | !-- Collision efficiencies are calculated for every new |
|---|
| 656 | !-- grid box. First, allocate memory for kernel table. |
|---|
| 657 | !-- Third dimension is 1, because table is re-calculated for |
|---|
| 658 | !-- every new dissipation value. |
|---|
| 659 | ALLOCATE( ckernel(psi:psi, psi:psi, 1:1) ) |
|---|
| 660 | ! |
|---|
| 661 | !-- Now calculate collision efficiencies for this box |
|---|
| 662 | CALL recalculate_kernel( i, j, k ) |
|---|
| 663 | |
|---|
| 664 | ddV = ddx * ddy / dz |
|---|
| 665 | sum3 = 1 - dt_3d * ddV * ( ckernel(psi,psi,1) * & |
|---|
| 666 | ( particles(psi)%weight_factor - 1 ) * 0.5_wp ) |
|---|
| 667 | |
|---|
| 668 | particles(psi)%radius = ( particles(psi)%radius**3 / & |
|---|
| 669 | sum3 )**0.33333333333333_wp |
|---|
| 670 | particles(psi)%weight_factor = particles(psi)%weight_factor & |
|---|
| 671 | * sum3 |
|---|
| 672 | |
|---|
| 673 | DEALLOCATE( ckernel ) |
|---|
| 674 | ENDIF |
|---|
| 675 | |
|---|
| 676 | ql_vp(k,j,i) = particles(psi)%weight_factor * & |
|---|
| 677 | particles(psi)%radius**3 |
|---|
| 678 | ENDIF |
|---|
| 679 | |
|---|
| 680 | ! |
|---|
| 681 | !-- Check if condensation of LWC was conserved during collision process |
|---|
| 682 | IF ( ql_v(k,j,i) /= 0.0_wp ) THEN |
|---|
| 683 | IF ( ql_vp(k,j,i) / ql_v(k,j,i) >= 1.0001_wp .OR. & |
|---|
| 684 | ql_vp(k,j,i) / ql_v(k,j,i) <= 0.9999_wp ) THEN |
|---|
| 685 | WRITE( message_string, * ) 'LWC is not conserved during',& |
|---|
| 686 | ' collision! ', & |
|---|
| 687 | 'LWC after condensation: ', & |
|---|
| 688 | ql_v(k,j,i), & |
|---|
| 689 | ' LWC after collision: ', & |
|---|
| 690 | ql_vp(k,j,i) |
|---|
| 691 | CALL message( 'lpm_droplet_collision', 'PA0040', & |
|---|
| 692 | 2, 2, -1, 6, 1 ) |
|---|
| 693 | ENDIF |
|---|
| 694 | ENDIF |
|---|
| 695 | |
|---|
| 696 | CALL cpu_log( log_point_s(43), 'lpm_droplet_coll', 'stop' ) |
|---|
| 697 | |
|---|
| 698 | END SUBROUTINE lpm_droplet_collision |
|---|
