| [849] | 1 | SUBROUTINE lpm_droplet_collision |
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| 2 | |
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| 3 | !------------------------------------------------------------------------------! |
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| 4 | ! Current revisions: |
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| 5 | ! ------------------ |
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| [850] | 6 | ! |
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| [849] | 7 | ! |
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| 8 | ! Former revisions: |
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| 9 | ! ----------------- |
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| 10 | ! $Id: lpm_droplet_collision.f90 850 2012-03-15 12:09:25Z fricke $ |
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| 11 | ! |
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| [850] | 12 | ! 849 2012-03-15 10:35:09Z raasch |
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| 13 | ! initial revision (former part of advec_particles) |
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| [849] | 14 | ! |
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| [850] | 15 | ! |
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| [849] | 16 | ! Description: |
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| 17 | ! ------------ |
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| 18 | ! Calculates chang in droplet radius by collision. Droplet collision is |
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| 19 | ! calculated for each grid box seperately. Collision is parameterized by |
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| 20 | ! using collision kernels. Three different kernels are available: |
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| 21 | ! PALM kernel: Kernel is approximated using a method from Rogers and |
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| 22 | ! Yau (1989, A Short Course in Cloud Physics, Pergamon Press). |
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| 23 | ! All droplets smaller than the treated one are represented by |
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| 24 | ! one droplet with mean features. Collision efficiencies are taken |
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| 25 | ! from the respective table in Rogers and Yau. |
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| 26 | ! Hall kernel: Kernel from Hall (1980, J. Atmos. Sci., 2486-2507), which |
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| 27 | ! considers collision due to pure gravitational effects. |
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| 28 | ! Wang kernel: Beside gravitational effects (treated with the Hall-kernel) also |
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| 29 | ! the effects of turbulence on the collision are considered using |
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| 30 | ! parameterizations of Ayala et al. (2008, New J. Phys., 10, |
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| 31 | ! 075015) and Wang and Grabowski (2009, Atmos. Sci. Lett., 10, |
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| 32 | ! 1-8). This kernel includes three possible effects of turbulence: |
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| 33 | ! the modification of the relative velocity between the droplets, |
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| 34 | ! the effect of preferential concentration, and the enhancement of |
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| 35 | ! collision efficiencies. |
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| 36 | !------------------------------------------------------------------------------! |
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| 37 | |
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| 38 | USE arrays_3d |
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| 39 | USE cloud_parameters |
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| 40 | USE constants |
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| 41 | USE control_parameters |
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| 42 | USE cpulog |
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| 43 | USE grid_variables |
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| 44 | USE indices |
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| 45 | USE interfaces |
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| 46 | USE lpm_collision_kernels_mod |
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| 47 | USE particle_attributes |
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| 48 | |
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| 49 | IMPLICIT NONE |
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| 50 | |
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| 51 | INTEGER :: eclass, i, ii, inc, is, j, jj, js, k, kk, n, pse, psi, & |
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| 52 | rclass_l, rclass_s |
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| 53 | |
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| 54 | REAL :: aa, bb, cc, dd, delta_r, delta_v, gg, epsilon, integral, lw_max, & |
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| 55 | mean_r, ql_int, ql_int_l, ql_int_u, u_int, u_int_l, u_int_u, & |
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| 56 | v_int, v_int_l, v_int_u, w_int, w_int_l, w_int_u, sl_r3, sl_r4, & |
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| 57 | x, y |
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| 58 | |
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| 59 | TYPE(particle_type) :: tmp_particle |
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| 60 | |
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| 61 | |
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| 62 | CALL cpu_log( log_point_s(43), 'lpm_droplet_coll', 'start' ) |
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| 63 | |
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| 64 | DO i = nxl, nxr |
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| 65 | DO j = nys, nyn |
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| 66 | DO k = nzb+1, nzt |
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| 67 | ! |
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| 68 | !-- Collision requires at least two particles in the box |
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| 69 | IF ( prt_count(k,j,i) > 1 ) THEN |
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| 70 | ! |
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| 71 | !-- First, sort particles within the gridbox by their size, |
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| 72 | !-- using Shell's method (see Numerical Recipes) |
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| 73 | !-- NOTE: In case of using particle tails, the re-sorting of |
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| 74 | !-- ---- tails would have to be included here! |
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| 75 | psi = prt_start_index(k,j,i) - 1 |
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| 76 | inc = 1 |
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| 77 | DO WHILE ( inc <= prt_count(k,j,i) ) |
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| 78 | inc = 3 * inc + 1 |
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| 79 | ENDDO |
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| 80 | |
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| 81 | DO WHILE ( inc > 1 ) |
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| 82 | inc = inc / 3 |
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| 83 | DO is = inc+1, prt_count(k,j,i) |
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| 84 | tmp_particle = particles(psi+is) |
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| 85 | js = is |
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| 86 | DO WHILE ( particles(psi+js-inc)%radius > & |
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| 87 | tmp_particle%radius ) |
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| 88 | particles(psi+js) = particles(psi+js-inc) |
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| 89 | js = js - inc |
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| 90 | IF ( js <= inc ) EXIT |
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| 91 | ENDDO |
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| 92 | particles(psi+js) = tmp_particle |
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| 93 | ENDDO |
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| 94 | ENDDO |
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| 95 | |
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| 96 | psi = prt_start_index(k,j,i) |
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| 97 | pse = psi + prt_count(k,j,i)-1 |
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| 98 | |
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| 99 | ! |
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| 100 | !-- Now apply the different kernels |
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| 101 | IF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
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| 102 | use_kernel_tables ) THEN |
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| 103 | ! |
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| 104 | !-- Fast method with pre-calculated efficiencies for |
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| 105 | !-- discrete radius- and dissipation-classes. |
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| 106 | ! |
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| 107 | !-- Determine dissipation class index of this gridbox |
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| 108 | IF ( wang_kernel ) THEN |
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| 109 | eclass = INT( diss(k,j,i) * 1.0E4 / 1000.0 * & |
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| 110 | dissipation_classes ) + 1 |
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| 111 | epsilon = diss(k,j,i) |
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| 112 | ELSE |
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| 113 | epsilon = 0.0 |
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| 114 | ENDIF |
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| 115 | IF ( hall_kernel .OR. epsilon * 1.0E4 < 0.001 ) THEN |
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| 116 | eclass = 0 ! Hall kernel is used |
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| 117 | ELSE |
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| 118 | eclass = MIN( dissipation_classes, eclass ) |
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| 119 | ENDIF |
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| 120 | |
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| 121 | DO n = pse, psi+1, -1 |
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| 122 | |
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| 123 | integral = 0.0 |
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| 124 | lw_max = 0.0 |
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| 125 | rclass_l = particles(n)%class |
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| 126 | ! |
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| 127 | !-- Calculate growth of collector particle radius using all |
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| 128 | !-- droplets smaller than current droplet |
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| 129 | DO is = psi, n-1 |
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| 130 | |
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| 131 | rclass_s = particles(is)%class |
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| 132 | integral = integral + & |
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| 133 | ( particles(is)%radius**3 * & |
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| 134 | ckernel(rclass_l,rclass_s,eclass) * & |
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| 135 | particles(is)%weight_factor ) |
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| 136 | ! |
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| 137 | !-- Calculate volume of liquid water of the collected |
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| 138 | !-- droplets which is the maximum liquid water available |
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| 139 | !-- for droplet growth |
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| 140 | lw_max = lw_max + ( particles(is)%radius**3 * & |
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| 141 | particles(is)%weight_factor ) |
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| 142 | |
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| 143 | ENDDO |
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| 144 | |
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| 145 | ! |
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| 146 | !-- Change in radius of collector droplet due to collision |
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| 147 | delta_r = 1.0 / ( 3.0 * particles(n)%radius**2 ) * & |
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| 148 | integral * dt_3d * ddx * ddy / dz |
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| 149 | |
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| 150 | ! |
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| 151 | !-- Change in volume of collector droplet due to collision |
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| 152 | delta_v = particles(n)%weight_factor & |
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| 153 | * ( ( particles(n)%radius + delta_r )**3 & |
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| 154 | - particles(n)%radius**3 ) |
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| 155 | |
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| 156 | IF ( lw_max < delta_v .AND. delta_v > 0.0 ) THEN |
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| 157 | !-- replace by message call |
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| 158 | PRINT*, 'Particle has grown to much because the', & |
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| 159 | ' change of volume of particle is larger', & |
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| 160 | ' than liquid water available!' |
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| 161 | |
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| 162 | ELSEIF ( lw_max == delta_v .AND. delta_v > 0.0 ) THEN |
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| 163 | !-- can this case really happen?? |
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| 164 | DO is = psi, n-1 |
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| 165 | |
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| 166 | particles(is)%weight_factor = 0.0 |
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| 167 | particle_mask(is) = .FALSE. |
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| 168 | deleted_particles = deleted_particles + 1 |
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| 169 | |
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| 170 | ENDDO |
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| 171 | |
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| 172 | ELSEIF ( lw_max > delta_v .AND. delta_v > 0.0 ) THEN |
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| 173 | ! |
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| 174 | !-- Calculate new weighting factor of collected droplets |
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| 175 | DO is = psi, n-1 |
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| 176 | |
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| 177 | rclass_s = particles(is)%class |
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| 178 | particles(is)%weight_factor = & |
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| 179 | particles(is)%weight_factor - & |
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| 180 | ( ( ckernel(rclass_l,rclass_s,eclass) * particles(is)%weight_factor & |
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| 181 | / integral ) * delta_v ) |
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| 182 | |
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| 183 | IF ( particles(is)%weight_factor < 0.0 ) THEN |
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| 184 | WRITE( message_string, * ) 'negative ', & |
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| 185 | 'weighting factor: ', & |
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| 186 | particles(is)%weight_factor |
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| 187 | CALL message( 'lpm_droplet_collision', '', & |
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| 188 | 2, 2, -1, 6, 1 ) |
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| 189 | |
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| 190 | ELSEIF ( particles(is)%weight_factor == 0.0 ) & |
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| 191 | THEN |
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| 192 | |
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| 193 | particles(is)%weight_factor = 0.0 |
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| 194 | particle_mask(is) = .FALSE. |
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| 195 | deleted_particles = deleted_particles + 1 |
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| 196 | |
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| 197 | ENDIF |
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| 198 | |
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| 199 | ENDDO |
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| 200 | |
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| 201 | ENDIF |
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| 202 | |
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| 203 | particles(n)%radius = particles(n)%radius + delta_r |
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| 204 | ql_vp(k,j,i) = ql_vp(k,j,i) + particles(n)%weight_factor & |
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| 205 | * particles(n)%radius**3 |
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| 206 | |
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| 207 | ENDDO |
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| 208 | |
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| 209 | ELSEIF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
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| 210 | .NOT. use_kernel_tables ) THEN |
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| 211 | ! |
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| 212 | !-- Collision efficiencies are calculated for every new |
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| 213 | !-- grid box. First, allocate memory for kernel table. |
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| 214 | !-- Third dimension is 1, because table is re-calculated for |
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| 215 | !-- every new dissipation value. |
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| 216 | ALLOCATE( ckernel(prt_start_index(k,j,i): & |
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| 217 | prt_start_index(k,j,i)+prt_count(k,j,i)-1, & |
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| 218 | prt_start_index(k,j,i): & |
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| 219 | prt_start_index(k,j,i)+prt_count(k,j,i)-1,1:1) ) |
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| 220 | ! |
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| 221 | !-- Now calculate collision efficiencies for this box |
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| 222 | CALL recalculate_kernel( i, j, k ) |
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| 223 | |
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| 224 | DO n = pse, psi+1, -1 |
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| 225 | |
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| 226 | integral = 0.0 |
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| 227 | lw_max = 0.0 |
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| 228 | ! |
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| 229 | !-- Calculate growth of collector particle radius using all |
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| 230 | !-- droplets smaller than current droplet |
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| 231 | DO is = psi, n-1 |
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| 232 | |
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| 233 | integral = integral + particles(is)%radius**3 * & |
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| 234 | ckernel(n,is,1) * & |
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| 235 | particles(is)%weight_factor |
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| 236 | ! |
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| 237 | !-- Calculate volume of liquid water of the collected |
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| 238 | !-- droplets which is the maximum liquid water available |
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| 239 | !-- for droplet growth |
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| 240 | lw_max = lw_max + ( particles(is)%radius**3 * & |
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| 241 | particles(is)%weight_factor ) |
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| 242 | |
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| 243 | ENDDO |
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| 244 | |
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| 245 | ! |
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| 246 | !-- Change in radius of collector droplet due to collision |
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| 247 | delta_r = 1.0 / ( 3.0 * particles(n)%radius**2 ) * & |
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| 248 | integral * dt_3d * ddx * ddy / dz |
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| 249 | |
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| 250 | ! |
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| 251 | !-- Change in volume of collector droplet due to collision |
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| 252 | delta_v = particles(n)%weight_factor & |
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| 253 | * ( ( particles(n)%radius + delta_r )**3 & |
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| 254 | - particles(n)%radius**3 ) |
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| 255 | |
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| 256 | IF ( lw_max < delta_v .AND. delta_v > 0.0 ) THEN |
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| 257 | !-- replace by message call |
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| 258 | PRINT*, 'Particle has grown to much because the', & |
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| 259 | ' change of volume of particle is larger', & |
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| 260 | ' than liquid water available!' |
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| 261 | |
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| 262 | ELSEIF ( lw_max == delta_v .AND. delta_v > 0.0 ) THEN |
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| 263 | !-- can this case really happen?? |
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| 264 | DO is = psi, n-1 |
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| 265 | |
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| 266 | particles(is)%weight_factor = 0.0 |
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| 267 | particle_mask(is) = .FALSE. |
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| 268 | deleted_particles = deleted_particles + 1 |
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| 269 | |
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| 270 | ENDDO |
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| 271 | |
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| 272 | ELSEIF ( lw_max > delta_v .AND. delta_v > 0.0 ) THEN |
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| 273 | ! |
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| 274 | !-- Calculate new weighting factor of collected droplets |
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| 275 | DO is = psi, n-1 |
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| 276 | |
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| 277 | particles(is)%weight_factor = & |
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| 278 | particles(is)%weight_factor - & |
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| 279 | ( ckernel(n,is,1) / integral * delta_v * & |
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| 280 | particles(is)%weight_factor ) |
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| 281 | |
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| 282 | IF ( particles(is)%weight_factor < 0.0 ) THEN |
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| 283 | WRITE( message_string, * ) 'negative ', & |
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| 284 | 'weighting factor: ', & |
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| 285 | particles(is)%weight_factor |
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| 286 | CALL message( 'lpm_droplet_collision', '', & |
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| 287 | 2, 2, -1, 6, 1 ) |
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| 288 | |
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| 289 | ELSEIF ( particles(is)%weight_factor == 0.0 ) & |
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| 290 | THEN |
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| 291 | |
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| 292 | particles(is)%weight_factor = 0.0 |
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| 293 | particle_mask(is) = .FALSE. |
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| 294 | deleted_particles = deleted_particles + 1 |
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| 295 | |
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| 296 | ENDIF |
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| 297 | |
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| 298 | ENDDO |
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| 299 | |
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| 300 | ENDIF |
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| 301 | |
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| 302 | particles(n)%radius = particles(n)%radius + delta_r |
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| 303 | ql_vp(k,j,i) = ql_vp(k,j,i) + particles(n)%weight_factor & |
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| 304 | * particles(n)%radius**3 |
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| 305 | |
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| 306 | ENDDO |
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| 307 | |
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| 308 | DEALLOCATE( ckernel ) |
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| 309 | |
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| 310 | ELSEIF ( palm_kernel ) THEN |
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| 311 | ! |
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| 312 | !-- PALM collision kernel |
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| 313 | ! |
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| 314 | !-- Calculate the mean radius of all those particles which |
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| 315 | !-- are of smaller size than the current particle and |
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| 316 | !-- use this radius for calculating the collision efficiency |
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| 317 | DO n = psi+prt_count(k,j,i)-1, psi+1, -1 |
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| 318 | |
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| 319 | sl_r3 = 0.0 |
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| 320 | sl_r4 = 0.0 |
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| 321 | |
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| 322 | DO is = n-1, psi, -1 |
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| 323 | IF ( particles(is)%radius < particles(n)%radius ) & |
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| 324 | THEN |
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| 325 | sl_r3 = sl_r3 + particles(is)%weight_factor & |
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| 326 | * particles(is)%radius**3 |
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| 327 | sl_r4 = sl_r4 + particles(is)%weight_factor & |
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| 328 | * particles(is)%radius**4 |
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| 329 | ENDIF |
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| 330 | ENDDO |
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| 331 | |
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| 332 | IF ( ( sl_r3 ) > 0.0 ) THEN |
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| 333 | mean_r = ( sl_r4 ) / ( sl_r3 ) |
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| 334 | |
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| 335 | CALL collision_efficiency_rogers( mean_r, & |
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| 336 | particles(n)%radius, & |
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| 337 | effective_coll_efficiency ) |
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| 338 | |
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| 339 | ELSE |
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| 340 | effective_coll_efficiency = 0.0 |
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| 341 | ENDIF |
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| 342 | |
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| 343 | IF ( effective_coll_efficiency > 1.0 .OR. & |
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| 344 | effective_coll_efficiency < 0.0 ) & |
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| 345 | THEN |
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| 346 | WRITE( message_string, * ) 'collision_efficien' , & |
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| 347 | 'cy out of range:' ,effective_coll_efficiency |
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| 348 | CALL message( 'lpm_droplet_collision', 'PA0145', 2, & |
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| 349 | 2, -1, 6, 1 ) |
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| 350 | ENDIF |
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| 351 | |
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| 352 | ! |
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| 353 | !-- Interpolation of ... |
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| 354 | ii = particles(n)%x * ddx |
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| 355 | jj = particles(n)%y * ddy |
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| 356 | kk = ( particles(n)%z + 0.5 * dz ) / dz |
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| 357 | |
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| 358 | x = particles(n)%x - ii * dx |
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| 359 | y = particles(n)%y - jj * dy |
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| 360 | aa = x**2 + y**2 |
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| 361 | bb = ( dx - x )**2 + y**2 |
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| 362 | cc = x**2 + ( dy - y )**2 |
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| 363 | dd = ( dx - x )**2 + ( dy - y )**2 |
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| 364 | gg = aa + bb + cc + dd |
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| 365 | |
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| 366 | ql_int_l = ( (gg-aa) * ql(kk,jj,ii) + (gg-bb) * & |
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| 367 | ql(kk,jj,ii+1) & |
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| 368 | + (gg-cc) * ql(kk,jj+1,ii) + ( gg-dd ) * & |
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| 369 | ql(kk,jj+1,ii+1) & |
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| 370 | ) / ( 3.0 * gg ) |
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| 371 | |
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| 372 | ql_int_u = ( (gg-aa) * ql(kk+1,jj,ii) + (gg-bb) * & |
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| 373 | ql(kk+1,jj,ii+1) & |
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| 374 | + (gg-cc) * ql(kk+1,jj+1,ii) + (gg-dd) * & |
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| 375 | ql(kk+1,jj+1,ii+1) & |
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| 376 | ) / ( 3.0 * gg ) |
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| 377 | |
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| 378 | ql_int = ql_int_l + ( particles(n)%z - zu(kk) ) / dz *& |
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| 379 | ( ql_int_u - ql_int_l ) |
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| 380 | |
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| 381 | ! |
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| 382 | !-- Interpolate u velocity-component |
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| 383 | ii = ( particles(n)%x + 0.5 * dx ) * ddx |
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| 384 | jj = particles(n)%y * ddy |
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| 385 | kk = ( particles(n)%z + 0.5 * dz ) / dz ! only if eqist |
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| 386 | |
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| 387 | IF ( ( particles(n)%z - zu(kk) ) > (0.5*dz) ) kk = kk+1 |
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| 388 | |
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| 389 | x = particles(n)%x + ( 0.5 - ii ) * dx |
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| 390 | y = particles(n)%y - jj * dy |
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| 391 | aa = x**2 + y**2 |
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| 392 | bb = ( dx - x )**2 + y**2 |
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| 393 | cc = x**2 + ( dy - y )**2 |
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| 394 | dd = ( dx - x )**2 + ( dy - y )**2 |
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| 395 | gg = aa + bb + cc + dd |
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| 396 | |
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| 397 | u_int_l = ( (gg-aa) * u(kk,jj,ii) + (gg-bb) * & |
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| 398 | u(kk,jj,ii+1) & |
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| 399 | + (gg-cc) * u(kk,jj+1,ii) + (gg-dd) * & |
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| 400 | u(kk,jj+1,ii+1) & |
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| 401 | ) / ( 3.0 * gg ) - u_gtrans |
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| 402 | IF ( kk+1 == nzt+1 ) THEN |
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| 403 | u_int = u_int_l |
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| 404 | ELSE |
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| 405 | u_int_u = ( (gg-aa) * u(kk+1,jj,ii) + (gg-bb) * & |
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| 406 | u(kk+1,jj,ii+1) & |
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| 407 | + (gg-cc) * u(kk+1,jj+1,ii) + (gg-dd) * & |
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| 408 | u(kk+1,jj+1,ii+1) & |
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| 409 | ) / ( 3.0 * gg ) - u_gtrans |
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| 410 | u_int = u_int_l + ( particles(n)%z - zu(kk) ) / dz & |
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| 411 | * ( u_int_u - u_int_l ) |
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| 412 | ENDIF |
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| 413 | |
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| 414 | ! |
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| 415 | !-- Same procedure for interpolation of the v velocity-com- |
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| 416 | !-- ponent (adopt index k from u velocity-component) |
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| 417 | ii = particles(n)%x * ddx |
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| 418 | jj = ( particles(n)%y + 0.5 * dy ) * ddy |
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| 419 | |
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| 420 | x = particles(n)%x - ii * dx |
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| 421 | y = particles(n)%y + ( 0.5 - jj ) * dy |
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| 422 | aa = x**2 + y**2 |
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| 423 | bb = ( dx - x )**2 + y**2 |
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| 424 | cc = x**2 + ( dy - y )**2 |
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| 425 | dd = ( dx - x )**2 + ( dy - y )**2 |
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| 426 | gg = aa + bb + cc + dd |
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| 427 | |
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| 428 | v_int_l = ( ( gg-aa ) * v(kk,jj,ii) + ( gg-bb ) * & |
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| 429 | v(kk,jj,ii+1) & |
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| 430 | + ( gg-cc ) * v(kk,jj+1,ii) + ( gg-dd ) * & |
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| 431 | v(kk,jj+1,ii+1) & |
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| 432 | ) / ( 3.0 * gg ) - v_gtrans |
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| 433 | IF ( kk+1 == nzt+1 ) THEN |
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| 434 | v_int = v_int_l |
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| 435 | ELSE |
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| 436 | v_int_u = ( (gg-aa) * v(kk+1,jj,ii) + (gg-bb) * & |
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| 437 | v(kk+1,jj,ii+1) & |
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| 438 | + (gg-cc) * v(kk+1,jj+1,ii) + (gg-dd) * & |
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| 439 | v(kk+1,jj+1,ii+1) & |
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| 440 | ) / ( 3.0 * gg ) - v_gtrans |
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| 441 | v_int = v_int_l + ( particles(n)%z - zu(kk) ) / dz & |
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| 442 | * ( v_int_u - v_int_l ) |
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| 443 | ENDIF |
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| 444 | |
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| 445 | ! |
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| 446 | !-- Same procedure for interpolation of the w velocity-com- |
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| 447 | !-- ponent (adopt index i from v velocity-component) |
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| 448 | jj = particles(n)%y * ddy |
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| 449 | kk = particles(n)%z / dz |
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| 450 | |
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| 451 | x = particles(n)%x - ii * dx |
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| 452 | y = particles(n)%y - jj * dy |
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| 453 | aa = x**2 + y**2 |
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| 454 | bb = ( dx - x )**2 + y**2 |
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| 455 | cc = x**2 + ( dy - y )**2 |
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| 456 | dd = ( dx - x )**2 + ( dy - y )**2 |
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| 457 | gg = aa + bb + cc + dd |
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| 458 | |
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| 459 | w_int_l = ( ( gg-aa ) * w(kk,jj,ii) + ( gg-bb ) * & |
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| 460 | w(kk,jj,ii+1) & |
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| 461 | + ( gg-cc ) * w(kk,jj+1,ii) + ( gg-dd ) * & |
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| 462 | w(kk,jj+1,ii+1) & |
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| 463 | ) / ( 3.0 * gg ) |
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| 464 | IF ( kk+1 == nzt+1 ) THEN |
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| 465 | w_int = w_int_l |
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| 466 | ELSE |
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| 467 | w_int_u = ( (gg-aa) * w(kk+1,jj,ii) + (gg-bb) * & |
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| 468 | w(kk+1,jj,ii+1) & |
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| 469 | + (gg-cc) * w(kk+1,jj+1,ii) + (gg-dd) * & |
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| 470 | w(kk+1,jj+1,ii+1) & |
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| 471 | ) / ( 3.0 * gg ) |
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| 472 | w_int = w_int_l + ( particles(n)%z - zw(kk) ) / dz & |
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| 473 | * ( w_int_u - w_int_l ) |
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| 474 | ENDIF |
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| 475 | |
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| 476 | ! |
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| 477 | !-- Change in radius due to collision |
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| 478 | delta_r = effective_coll_efficiency / 3.0 & |
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| 479 | * pi * sl_r3 * ddx * ddy / dz & |
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| 480 | * SQRT( ( u_int - particles(n)%speed_x )**2 & |
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| 481 | + ( v_int - particles(n)%speed_y )**2 & |
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| 482 | + ( w_int - particles(n)%speed_z )**2 & |
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| 483 | ) * dt_3d |
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| 484 | ! |
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| 485 | !-- Change in volume due to collision |
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| 486 | delta_v = particles(n)%weight_factor & |
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| 487 | * ( ( particles(n)%radius + delta_r )**3 & |
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| 488 | - particles(n)%radius**3 ) |
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| 489 | |
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| 490 | ! |
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| 491 | !-- Check if collected particles provide enough LWC for |
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| 492 | !-- volume change of collector particle |
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| 493 | IF ( delta_v >= sl_r3 .AND. sl_r3 > 0.0 ) THEN |
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| 494 | |
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| 495 | delta_r = ( ( sl_r3/particles(n)%weight_factor ) & |
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| 496 | + particles(n)%radius**3 )**( 1./3. ) & |
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| 497 | - particles(n)%radius |
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| 498 | |
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| 499 | DO is = n-1, psi, -1 |
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| 500 | IF ( particles(is)%radius < & |
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| 501 | particles(n)%radius ) THEN |
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| 502 | particles(is)%weight_factor = 0.0 |
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| 503 | particle_mask(is) = .FALSE. |
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| 504 | deleted_particles = deleted_particles + 1 |
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| 505 | ENDIF |
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| 506 | ENDDO |
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| 507 | |
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| 508 | ELSE IF ( delta_v < sl_r3 .AND. sl_r3 > 0.0 ) THEN |
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| 509 | |
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| 510 | DO is = n-1, psi, -1 |
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| 511 | IF ( particles(is)%radius < particles(n)%radius & |
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| 512 | .AND. sl_r3 > 0.0 ) THEN |
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| 513 | particles(is)%weight_factor = & |
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| 514 | ( ( particles(is)%weight_factor & |
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| 515 | * ( particles(is)%radius**3 ) ) & |
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| 516 | - ( delta_v & |
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| 517 | * particles(is)%weight_factor & |
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| 518 | * ( particles(is)%radius**3 ) & |
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| 519 | / sl_r3 ) ) & |
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| 520 | / ( particles(is)%radius**3 ) |
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| 521 | |
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| 522 | IF ( particles(is)%weight_factor < 0.0 ) THEN |
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| 523 | WRITE( message_string, * ) 'negative ', & |
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| 524 | 'weighting factor: ', & |
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| 525 | particles(is)%weight_factor |
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| 526 | CALL message( 'lpm_droplet_collision', '', & |
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| 527 | 2, 2, -1, 6, 1 ) |
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| 528 | ENDIF |
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| 529 | ENDIF |
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| 530 | ENDDO |
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| 531 | |
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| 532 | ENDIF |
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| 533 | |
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| 534 | particles(n)%radius = particles(n)%radius + delta_r |
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| 535 | ql_vp(k,j,i) = ql_vp(k,j,i) + & |
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| 536 | particles(n)%weight_factor * & |
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| 537 | ( particles(n)%radius**3 ) |
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| 538 | ENDDO |
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| 539 | |
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| 540 | ENDIF ! collision kernel |
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| 541 | |
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| 542 | ql_vp(k,j,i) = ql_vp(k,j,i) + particles(psi)%weight_factor & |
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| 543 | * particles(psi)%radius**3 |
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| 544 | |
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| 545 | |
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| 546 | ELSE IF ( prt_count(k,j,i) == 1 ) THEN |
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| 547 | |
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| 548 | psi = prt_start_index(k,j,i) |
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| 549 | ql_vp(k,j,i) = particles(psi)%weight_factor * & |
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| 550 | particles(psi)%radius**3 |
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| 551 | ENDIF |
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| 552 | |
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| 553 | ! |
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| 554 | !-- Check if condensation of LWC was conserved during collision |
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| 555 | !-- process |
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| 556 | IF ( ql_v(k,j,i) /= 0.0 ) THEN |
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| 557 | IF ( ql_vp(k,j,i) / ql_v(k,j,i) >= 1.0001 .OR. & |
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| 558 | ql_vp(k,j,i) / ql_v(k,j,i) <= 0.9999 ) THEN |
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| 559 | WRITE( message_string, * ) 'LWC is not conserved during',& |
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| 560 | ' collision! ', & |
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| 561 | 'LWC after condensation: ', & |
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| 562 | ql_v(k,j,i), & |
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| 563 | ' LWC after collision: ', & |
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| 564 | ql_vp(k,j,i) |
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| 565 | CALL message( 'lpm_droplet_collision', '', 2, 2, -1, 6, 1 ) |
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| 566 | ENDIF |
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| 567 | ENDIF |
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| 568 | |
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| 569 | ENDDO |
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| 570 | ENDDO |
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| 571 | ENDDO |
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| 572 | |
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| 573 | CALL cpu_log( log_point_s(43), 'lpm_droplet_coll', 'stop' ) |
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| 574 | |
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| 575 | |
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| 576 | END SUBROUTINE lpm_droplet_collision |
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