[849] | 1 | SUBROUTINE lpm_droplet_collision |
---|
| 2 | |
---|
[1036] | 3 | !--------------------------------------------------------------------------------! |
---|
| 4 | ! This file is part of PALM. |
---|
| 5 | ! |
---|
| 6 | ! PALM is free software: you can redistribute it and/or modify it under the terms |
---|
| 7 | ! of the GNU General Public License as published by the Free Software Foundation, |
---|
| 8 | ! either version 3 of the License, or (at your option) any later version. |
---|
| 9 | ! |
---|
| 10 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY |
---|
| 11 | ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
---|
| 12 | ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
---|
| 13 | ! |
---|
| 14 | ! You should have received a copy of the GNU General Public License along with |
---|
| 15 | ! PALM. If not, see <http://www.gnu.org/licenses/>. |
---|
| 16 | ! |
---|
| 17 | ! Copyright 1997-2012 Leibniz University Hannover |
---|
| 18 | !--------------------------------------------------------------------------------! |
---|
| 19 | ! |
---|
[849] | 20 | ! Current revisions: |
---|
| 21 | ! ------------------ |
---|
[850] | 22 | ! |
---|
[849] | 23 | ! |
---|
| 24 | ! Former revisions: |
---|
| 25 | ! ----------------- |
---|
| 26 | ! $Id: lpm_droplet_collision.f90 1037 2012-10-22 14:10:22Z hoffmann $ |
---|
| 27 | ! |
---|
[1037] | 28 | ! 1036 2012-10-22 13:43:42Z raasch |
---|
| 29 | ! code put under GPL (PALM 3.9) |
---|
| 30 | ! |
---|
[850] | 31 | ! 849 2012-03-15 10:35:09Z raasch |
---|
| 32 | ! initial revision (former part of advec_particles) |
---|
[849] | 33 | ! |
---|
[850] | 34 | ! |
---|
[849] | 35 | ! Description: |
---|
| 36 | ! ------------ |
---|
| 37 | ! Calculates chang in droplet radius by collision. Droplet collision is |
---|
| 38 | ! calculated for each grid box seperately. Collision is parameterized by |
---|
| 39 | ! using collision kernels. Three different kernels are available: |
---|
| 40 | ! PALM kernel: Kernel is approximated using a method from Rogers and |
---|
| 41 | ! Yau (1989, A Short Course in Cloud Physics, Pergamon Press). |
---|
| 42 | ! All droplets smaller than the treated one are represented by |
---|
| 43 | ! one droplet with mean features. Collision efficiencies are taken |
---|
| 44 | ! from the respective table in Rogers and Yau. |
---|
| 45 | ! Hall kernel: Kernel from Hall (1980, J. Atmos. Sci., 2486-2507), which |
---|
| 46 | ! considers collision due to pure gravitational effects. |
---|
| 47 | ! Wang kernel: Beside gravitational effects (treated with the Hall-kernel) also |
---|
| 48 | ! the effects of turbulence on the collision are considered using |
---|
| 49 | ! parameterizations of Ayala et al. (2008, New J. Phys., 10, |
---|
| 50 | ! 075015) and Wang and Grabowski (2009, Atmos. Sci. Lett., 10, |
---|
| 51 | ! 1-8). This kernel includes three possible effects of turbulence: |
---|
| 52 | ! the modification of the relative velocity between the droplets, |
---|
| 53 | ! the effect of preferential concentration, and the enhancement of |
---|
| 54 | ! collision efficiencies. |
---|
| 55 | !------------------------------------------------------------------------------! |
---|
| 56 | |
---|
| 57 | USE arrays_3d |
---|
| 58 | USE cloud_parameters |
---|
| 59 | USE constants |
---|
| 60 | USE control_parameters |
---|
| 61 | USE cpulog |
---|
| 62 | USE grid_variables |
---|
| 63 | USE indices |
---|
| 64 | USE interfaces |
---|
| 65 | USE lpm_collision_kernels_mod |
---|
| 66 | USE particle_attributes |
---|
| 67 | |
---|
| 68 | IMPLICIT NONE |
---|
| 69 | |
---|
| 70 | INTEGER :: eclass, i, ii, inc, is, j, jj, js, k, kk, n, pse, psi, & |
---|
| 71 | rclass_l, rclass_s |
---|
| 72 | |
---|
| 73 | REAL :: aa, bb, cc, dd, delta_r, delta_v, gg, epsilon, integral, lw_max, & |
---|
| 74 | mean_r, ql_int, ql_int_l, ql_int_u, u_int, u_int_l, u_int_u, & |
---|
| 75 | v_int, v_int_l, v_int_u, w_int, w_int_l, w_int_u, sl_r3, sl_r4, & |
---|
| 76 | x, y |
---|
| 77 | |
---|
| 78 | TYPE(particle_type) :: tmp_particle |
---|
| 79 | |
---|
| 80 | |
---|
| 81 | CALL cpu_log( log_point_s(43), 'lpm_droplet_coll', 'start' ) |
---|
| 82 | |
---|
| 83 | DO i = nxl, nxr |
---|
| 84 | DO j = nys, nyn |
---|
| 85 | DO k = nzb+1, nzt |
---|
| 86 | ! |
---|
| 87 | !-- Collision requires at least two particles in the box |
---|
| 88 | IF ( prt_count(k,j,i) > 1 ) THEN |
---|
| 89 | ! |
---|
| 90 | !-- First, sort particles within the gridbox by their size, |
---|
| 91 | !-- using Shell's method (see Numerical Recipes) |
---|
| 92 | !-- NOTE: In case of using particle tails, the re-sorting of |
---|
| 93 | !-- ---- tails would have to be included here! |
---|
| 94 | psi = prt_start_index(k,j,i) - 1 |
---|
| 95 | inc = 1 |
---|
| 96 | DO WHILE ( inc <= prt_count(k,j,i) ) |
---|
| 97 | inc = 3 * inc + 1 |
---|
| 98 | ENDDO |
---|
| 99 | |
---|
| 100 | DO WHILE ( inc > 1 ) |
---|
| 101 | inc = inc / 3 |
---|
| 102 | DO is = inc+1, prt_count(k,j,i) |
---|
| 103 | tmp_particle = particles(psi+is) |
---|
| 104 | js = is |
---|
| 105 | DO WHILE ( particles(psi+js-inc)%radius > & |
---|
| 106 | tmp_particle%radius ) |
---|
| 107 | particles(psi+js) = particles(psi+js-inc) |
---|
| 108 | js = js - inc |
---|
| 109 | IF ( js <= inc ) EXIT |
---|
| 110 | ENDDO |
---|
| 111 | particles(psi+js) = tmp_particle |
---|
| 112 | ENDDO |
---|
| 113 | ENDDO |
---|
| 114 | |
---|
| 115 | psi = prt_start_index(k,j,i) |
---|
| 116 | pse = psi + prt_count(k,j,i)-1 |
---|
| 117 | |
---|
| 118 | ! |
---|
| 119 | !-- Now apply the different kernels |
---|
| 120 | IF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
---|
| 121 | use_kernel_tables ) THEN |
---|
| 122 | ! |
---|
| 123 | !-- Fast method with pre-calculated efficiencies for |
---|
| 124 | !-- discrete radius- and dissipation-classes. |
---|
| 125 | ! |
---|
| 126 | !-- Determine dissipation class index of this gridbox |
---|
| 127 | IF ( wang_kernel ) THEN |
---|
| 128 | eclass = INT( diss(k,j,i) * 1.0E4 / 1000.0 * & |
---|
| 129 | dissipation_classes ) + 1 |
---|
| 130 | epsilon = diss(k,j,i) |
---|
| 131 | ELSE |
---|
| 132 | epsilon = 0.0 |
---|
| 133 | ENDIF |
---|
| 134 | IF ( hall_kernel .OR. epsilon * 1.0E4 < 0.001 ) THEN |
---|
| 135 | eclass = 0 ! Hall kernel is used |
---|
| 136 | ELSE |
---|
| 137 | eclass = MIN( dissipation_classes, eclass ) |
---|
| 138 | ENDIF |
---|
| 139 | |
---|
| 140 | DO n = pse, psi+1, -1 |
---|
| 141 | |
---|
| 142 | integral = 0.0 |
---|
| 143 | lw_max = 0.0 |
---|
| 144 | rclass_l = particles(n)%class |
---|
| 145 | ! |
---|
| 146 | !-- Calculate growth of collector particle radius using all |
---|
| 147 | !-- droplets smaller than current droplet |
---|
| 148 | DO is = psi, n-1 |
---|
| 149 | |
---|
| 150 | rclass_s = particles(is)%class |
---|
| 151 | integral = integral + & |
---|
| 152 | ( particles(is)%radius**3 * & |
---|
| 153 | ckernel(rclass_l,rclass_s,eclass) * & |
---|
| 154 | particles(is)%weight_factor ) |
---|
| 155 | ! |
---|
| 156 | !-- Calculate volume of liquid water of the collected |
---|
| 157 | !-- droplets which is the maximum liquid water available |
---|
| 158 | !-- for droplet growth |
---|
| 159 | lw_max = lw_max + ( particles(is)%radius**3 * & |
---|
| 160 | particles(is)%weight_factor ) |
---|
| 161 | |
---|
| 162 | ENDDO |
---|
| 163 | |
---|
| 164 | ! |
---|
| 165 | !-- Change in radius of collector droplet due to collision |
---|
| 166 | delta_r = 1.0 / ( 3.0 * particles(n)%radius**2 ) * & |
---|
| 167 | integral * dt_3d * ddx * ddy / dz |
---|
| 168 | |
---|
| 169 | ! |
---|
| 170 | !-- Change in volume of collector droplet due to collision |
---|
| 171 | delta_v = particles(n)%weight_factor & |
---|
| 172 | * ( ( particles(n)%radius + delta_r )**3 & |
---|
| 173 | - particles(n)%radius**3 ) |
---|
| 174 | |
---|
| 175 | IF ( lw_max < delta_v .AND. delta_v > 0.0 ) THEN |
---|
| 176 | !-- replace by message call |
---|
| 177 | PRINT*, 'Particle has grown to much because the', & |
---|
| 178 | ' change of volume of particle is larger', & |
---|
| 179 | ' than liquid water available!' |
---|
| 180 | |
---|
| 181 | ELSEIF ( lw_max == delta_v .AND. delta_v > 0.0 ) THEN |
---|
| 182 | !-- can this case really happen?? |
---|
| 183 | DO is = psi, n-1 |
---|
| 184 | |
---|
| 185 | particles(is)%weight_factor = 0.0 |
---|
| 186 | particle_mask(is) = .FALSE. |
---|
| 187 | deleted_particles = deleted_particles + 1 |
---|
| 188 | |
---|
| 189 | ENDDO |
---|
| 190 | |
---|
| 191 | ELSEIF ( lw_max > delta_v .AND. delta_v > 0.0 ) THEN |
---|
| 192 | ! |
---|
| 193 | !-- Calculate new weighting factor of collected droplets |
---|
| 194 | DO is = psi, n-1 |
---|
| 195 | |
---|
| 196 | rclass_s = particles(is)%class |
---|
| 197 | particles(is)%weight_factor = & |
---|
| 198 | particles(is)%weight_factor - & |
---|
| 199 | ( ( ckernel(rclass_l,rclass_s,eclass) * particles(is)%weight_factor & |
---|
| 200 | / integral ) * delta_v ) |
---|
| 201 | |
---|
| 202 | IF ( particles(is)%weight_factor < 0.0 ) THEN |
---|
| 203 | WRITE( message_string, * ) 'negative ', & |
---|
| 204 | 'weighting factor: ', & |
---|
| 205 | particles(is)%weight_factor |
---|
| 206 | CALL message( 'lpm_droplet_collision', '', & |
---|
| 207 | 2, 2, -1, 6, 1 ) |
---|
| 208 | |
---|
| 209 | ELSEIF ( particles(is)%weight_factor == 0.0 ) & |
---|
| 210 | THEN |
---|
| 211 | |
---|
| 212 | particles(is)%weight_factor = 0.0 |
---|
| 213 | particle_mask(is) = .FALSE. |
---|
| 214 | deleted_particles = deleted_particles + 1 |
---|
| 215 | |
---|
| 216 | ENDIF |
---|
| 217 | |
---|
| 218 | ENDDO |
---|
| 219 | |
---|
| 220 | ENDIF |
---|
| 221 | |
---|
| 222 | particles(n)%radius = particles(n)%radius + delta_r |
---|
| 223 | ql_vp(k,j,i) = ql_vp(k,j,i) + particles(n)%weight_factor & |
---|
| 224 | * particles(n)%radius**3 |
---|
| 225 | |
---|
| 226 | ENDDO |
---|
| 227 | |
---|
| 228 | ELSEIF ( ( hall_kernel .OR. wang_kernel ) .AND. & |
---|
| 229 | .NOT. use_kernel_tables ) THEN |
---|
| 230 | ! |
---|
| 231 | !-- Collision efficiencies are calculated for every new |
---|
| 232 | !-- grid box. First, allocate memory for kernel table. |
---|
| 233 | !-- Third dimension is 1, because table is re-calculated for |
---|
| 234 | !-- every new dissipation value. |
---|
| 235 | ALLOCATE( ckernel(prt_start_index(k,j,i): & |
---|
| 236 | prt_start_index(k,j,i)+prt_count(k,j,i)-1, & |
---|
| 237 | prt_start_index(k,j,i): & |
---|
| 238 | prt_start_index(k,j,i)+prt_count(k,j,i)-1,1:1) ) |
---|
| 239 | ! |
---|
| 240 | !-- Now calculate collision efficiencies for this box |
---|
| 241 | CALL recalculate_kernel( i, j, k ) |
---|
| 242 | |
---|
| 243 | DO n = pse, psi+1, -1 |
---|
| 244 | |
---|
| 245 | integral = 0.0 |
---|
| 246 | lw_max = 0.0 |
---|
| 247 | ! |
---|
| 248 | !-- Calculate growth of collector particle radius using all |
---|
| 249 | !-- droplets smaller than current droplet |
---|
| 250 | DO is = psi, n-1 |
---|
| 251 | |
---|
| 252 | integral = integral + particles(is)%radius**3 * & |
---|
| 253 | ckernel(n,is,1) * & |
---|
| 254 | particles(is)%weight_factor |
---|
| 255 | ! |
---|
| 256 | !-- Calculate volume of liquid water of the collected |
---|
| 257 | !-- droplets which is the maximum liquid water available |
---|
| 258 | !-- for droplet growth |
---|
| 259 | lw_max = lw_max + ( particles(is)%radius**3 * & |
---|
| 260 | particles(is)%weight_factor ) |
---|
| 261 | |
---|
| 262 | ENDDO |
---|
| 263 | |
---|
| 264 | ! |
---|
| 265 | !-- Change in radius of collector droplet due to collision |
---|
| 266 | delta_r = 1.0 / ( 3.0 * particles(n)%radius**2 ) * & |
---|
| 267 | integral * dt_3d * ddx * ddy / dz |
---|
| 268 | |
---|
| 269 | ! |
---|
| 270 | !-- Change in volume of collector droplet due to collision |
---|
| 271 | delta_v = particles(n)%weight_factor & |
---|
| 272 | * ( ( particles(n)%radius + delta_r )**3 & |
---|
| 273 | - particles(n)%radius**3 ) |
---|
| 274 | |
---|
| 275 | IF ( lw_max < delta_v .AND. delta_v > 0.0 ) THEN |
---|
| 276 | !-- replace by message call |
---|
| 277 | PRINT*, 'Particle has grown to much because the', & |
---|
| 278 | ' change of volume of particle is larger', & |
---|
| 279 | ' than liquid water available!' |
---|
| 280 | |
---|
| 281 | ELSEIF ( lw_max == delta_v .AND. delta_v > 0.0 ) THEN |
---|
| 282 | !-- can this case really happen?? |
---|
| 283 | DO is = psi, n-1 |
---|
| 284 | |
---|
| 285 | particles(is)%weight_factor = 0.0 |
---|
| 286 | particle_mask(is) = .FALSE. |
---|
| 287 | deleted_particles = deleted_particles + 1 |
---|
| 288 | |
---|
| 289 | ENDDO |
---|
| 290 | |
---|
| 291 | ELSEIF ( lw_max > delta_v .AND. delta_v > 0.0 ) THEN |
---|
| 292 | ! |
---|
| 293 | !-- Calculate new weighting factor of collected droplets |
---|
| 294 | DO is = psi, n-1 |
---|
| 295 | |
---|
| 296 | particles(is)%weight_factor = & |
---|
| 297 | particles(is)%weight_factor - & |
---|
| 298 | ( ckernel(n,is,1) / integral * delta_v * & |
---|
| 299 | particles(is)%weight_factor ) |
---|
| 300 | |
---|
| 301 | IF ( particles(is)%weight_factor < 0.0 ) THEN |
---|
| 302 | WRITE( message_string, * ) 'negative ', & |
---|
| 303 | 'weighting factor: ', & |
---|
| 304 | particles(is)%weight_factor |
---|
| 305 | CALL message( 'lpm_droplet_collision', '', & |
---|
| 306 | 2, 2, -1, 6, 1 ) |
---|
| 307 | |
---|
| 308 | ELSEIF ( particles(is)%weight_factor == 0.0 ) & |
---|
| 309 | THEN |
---|
| 310 | |
---|
| 311 | particles(is)%weight_factor = 0.0 |
---|
| 312 | particle_mask(is) = .FALSE. |
---|
| 313 | deleted_particles = deleted_particles + 1 |
---|
| 314 | |
---|
| 315 | ENDIF |
---|
| 316 | |
---|
| 317 | ENDDO |
---|
| 318 | |
---|
| 319 | ENDIF |
---|
| 320 | |
---|
| 321 | particles(n)%radius = particles(n)%radius + delta_r |
---|
| 322 | ql_vp(k,j,i) = ql_vp(k,j,i) + particles(n)%weight_factor & |
---|
| 323 | * particles(n)%radius**3 |
---|
| 324 | |
---|
| 325 | ENDDO |
---|
| 326 | |
---|
| 327 | DEALLOCATE( ckernel ) |
---|
| 328 | |
---|
| 329 | ELSEIF ( palm_kernel ) THEN |
---|
| 330 | ! |
---|
| 331 | !-- PALM collision kernel |
---|
| 332 | ! |
---|
| 333 | !-- Calculate the mean radius of all those particles which |
---|
| 334 | !-- are of smaller size than the current particle and |
---|
| 335 | !-- use this radius for calculating the collision efficiency |
---|
| 336 | DO n = psi+prt_count(k,j,i)-1, psi+1, -1 |
---|
| 337 | |
---|
| 338 | sl_r3 = 0.0 |
---|
| 339 | sl_r4 = 0.0 |
---|
| 340 | |
---|
| 341 | DO is = n-1, psi, -1 |
---|
| 342 | IF ( particles(is)%radius < particles(n)%radius ) & |
---|
| 343 | THEN |
---|
| 344 | sl_r3 = sl_r3 + particles(is)%weight_factor & |
---|
| 345 | * particles(is)%radius**3 |
---|
| 346 | sl_r4 = sl_r4 + particles(is)%weight_factor & |
---|
| 347 | * particles(is)%radius**4 |
---|
| 348 | ENDIF |
---|
| 349 | ENDDO |
---|
| 350 | |
---|
| 351 | IF ( ( sl_r3 ) > 0.0 ) THEN |
---|
| 352 | mean_r = ( sl_r4 ) / ( sl_r3 ) |
---|
| 353 | |
---|
| 354 | CALL collision_efficiency_rogers( mean_r, & |
---|
| 355 | particles(n)%radius, & |
---|
| 356 | effective_coll_efficiency ) |
---|
| 357 | |
---|
| 358 | ELSE |
---|
| 359 | effective_coll_efficiency = 0.0 |
---|
| 360 | ENDIF |
---|
| 361 | |
---|
| 362 | IF ( effective_coll_efficiency > 1.0 .OR. & |
---|
| 363 | effective_coll_efficiency < 0.0 ) & |
---|
| 364 | THEN |
---|
| 365 | WRITE( message_string, * ) 'collision_efficien' , & |
---|
| 366 | 'cy out of range:' ,effective_coll_efficiency |
---|
| 367 | CALL message( 'lpm_droplet_collision', 'PA0145', 2, & |
---|
| 368 | 2, -1, 6, 1 ) |
---|
| 369 | ENDIF |
---|
| 370 | |
---|
| 371 | ! |
---|
| 372 | !-- Interpolation of ... |
---|
| 373 | ii = particles(n)%x * ddx |
---|
| 374 | jj = particles(n)%y * ddy |
---|
| 375 | kk = ( particles(n)%z + 0.5 * dz ) / dz |
---|
| 376 | |
---|
| 377 | x = particles(n)%x - ii * dx |
---|
| 378 | y = particles(n)%y - jj * dy |
---|
| 379 | aa = x**2 + y**2 |
---|
| 380 | bb = ( dx - x )**2 + y**2 |
---|
| 381 | cc = x**2 + ( dy - y )**2 |
---|
| 382 | dd = ( dx - x )**2 + ( dy - y )**2 |
---|
| 383 | gg = aa + bb + cc + dd |
---|
| 384 | |
---|
| 385 | ql_int_l = ( (gg-aa) * ql(kk,jj,ii) + (gg-bb) * & |
---|
| 386 | ql(kk,jj,ii+1) & |
---|
| 387 | + (gg-cc) * ql(kk,jj+1,ii) + ( gg-dd ) * & |
---|
| 388 | ql(kk,jj+1,ii+1) & |
---|
| 389 | ) / ( 3.0 * gg ) |
---|
| 390 | |
---|
| 391 | ql_int_u = ( (gg-aa) * ql(kk+1,jj,ii) + (gg-bb) * & |
---|
| 392 | ql(kk+1,jj,ii+1) & |
---|
| 393 | + (gg-cc) * ql(kk+1,jj+1,ii) + (gg-dd) * & |
---|
| 394 | ql(kk+1,jj+1,ii+1) & |
---|
| 395 | ) / ( 3.0 * gg ) |
---|
| 396 | |
---|
| 397 | ql_int = ql_int_l + ( particles(n)%z - zu(kk) ) / dz *& |
---|
| 398 | ( ql_int_u - ql_int_l ) |
---|
| 399 | |
---|
| 400 | ! |
---|
| 401 | !-- Interpolate u velocity-component |
---|
| 402 | ii = ( particles(n)%x + 0.5 * dx ) * ddx |
---|
| 403 | jj = particles(n)%y * ddy |
---|
| 404 | kk = ( particles(n)%z + 0.5 * dz ) / dz ! only if eqist |
---|
| 405 | |
---|
| 406 | IF ( ( particles(n)%z - zu(kk) ) > (0.5*dz) ) kk = kk+1 |
---|
| 407 | |
---|
| 408 | x = particles(n)%x + ( 0.5 - ii ) * dx |
---|
| 409 | y = particles(n)%y - jj * dy |
---|
| 410 | aa = x**2 + y**2 |
---|
| 411 | bb = ( dx - x )**2 + y**2 |
---|
| 412 | cc = x**2 + ( dy - y )**2 |
---|
| 413 | dd = ( dx - x )**2 + ( dy - y )**2 |
---|
| 414 | gg = aa + bb + cc + dd |
---|
| 415 | |
---|
| 416 | u_int_l = ( (gg-aa) * u(kk,jj,ii) + (gg-bb) * & |
---|
| 417 | u(kk,jj,ii+1) & |
---|
| 418 | + (gg-cc) * u(kk,jj+1,ii) + (gg-dd) * & |
---|
| 419 | u(kk,jj+1,ii+1) & |
---|
| 420 | ) / ( 3.0 * gg ) - u_gtrans |
---|
| 421 | IF ( kk+1 == nzt+1 ) THEN |
---|
| 422 | u_int = u_int_l |
---|
| 423 | ELSE |
---|
| 424 | u_int_u = ( (gg-aa) * u(kk+1,jj,ii) + (gg-bb) * & |
---|
| 425 | u(kk+1,jj,ii+1) & |
---|
| 426 | + (gg-cc) * u(kk+1,jj+1,ii) + (gg-dd) * & |
---|
| 427 | u(kk+1,jj+1,ii+1) & |
---|
| 428 | ) / ( 3.0 * gg ) - u_gtrans |
---|
| 429 | u_int = u_int_l + ( particles(n)%z - zu(kk) ) / dz & |
---|
| 430 | * ( u_int_u - u_int_l ) |
---|
| 431 | ENDIF |
---|
| 432 | |
---|
| 433 | ! |
---|
| 434 | !-- Same procedure for interpolation of the v velocity-com- |
---|
| 435 | !-- ponent (adopt index k from u velocity-component) |
---|
| 436 | ii = particles(n)%x * ddx |
---|
| 437 | jj = ( particles(n)%y + 0.5 * dy ) * ddy |
---|
| 438 | |
---|
| 439 | x = particles(n)%x - ii * dx |
---|
| 440 | y = particles(n)%y + ( 0.5 - jj ) * dy |
---|
| 441 | aa = x**2 + y**2 |
---|
| 442 | bb = ( dx - x )**2 + y**2 |
---|
| 443 | cc = x**2 + ( dy - y )**2 |
---|
| 444 | dd = ( dx - x )**2 + ( dy - y )**2 |
---|
| 445 | gg = aa + bb + cc + dd |
---|
| 446 | |
---|
| 447 | v_int_l = ( ( gg-aa ) * v(kk,jj,ii) + ( gg-bb ) * & |
---|
| 448 | v(kk,jj,ii+1) & |
---|
| 449 | + ( gg-cc ) * v(kk,jj+1,ii) + ( gg-dd ) * & |
---|
| 450 | v(kk,jj+1,ii+1) & |
---|
| 451 | ) / ( 3.0 * gg ) - v_gtrans |
---|
| 452 | IF ( kk+1 == nzt+1 ) THEN |
---|
| 453 | v_int = v_int_l |
---|
| 454 | ELSE |
---|
| 455 | v_int_u = ( (gg-aa) * v(kk+1,jj,ii) + (gg-bb) * & |
---|
| 456 | v(kk+1,jj,ii+1) & |
---|
| 457 | + (gg-cc) * v(kk+1,jj+1,ii) + (gg-dd) * & |
---|
| 458 | v(kk+1,jj+1,ii+1) & |
---|
| 459 | ) / ( 3.0 * gg ) - v_gtrans |
---|
| 460 | v_int = v_int_l + ( particles(n)%z - zu(kk) ) / dz & |
---|
| 461 | * ( v_int_u - v_int_l ) |
---|
| 462 | ENDIF |
---|
| 463 | |
---|
| 464 | ! |
---|
| 465 | !-- Same procedure for interpolation of the w velocity-com- |
---|
| 466 | !-- ponent (adopt index i from v velocity-component) |
---|
| 467 | jj = particles(n)%y * ddy |
---|
| 468 | kk = particles(n)%z / dz |
---|
| 469 | |
---|
| 470 | x = particles(n)%x - ii * dx |
---|
| 471 | y = particles(n)%y - jj * dy |
---|
| 472 | aa = x**2 + y**2 |
---|
| 473 | bb = ( dx - x )**2 + y**2 |
---|
| 474 | cc = x**2 + ( dy - y )**2 |
---|
| 475 | dd = ( dx - x )**2 + ( dy - y )**2 |
---|
| 476 | gg = aa + bb + cc + dd |
---|
| 477 | |
---|
| 478 | w_int_l = ( ( gg-aa ) * w(kk,jj,ii) + ( gg-bb ) * & |
---|
| 479 | w(kk,jj,ii+1) & |
---|
| 480 | + ( gg-cc ) * w(kk,jj+1,ii) + ( gg-dd ) * & |
---|
| 481 | w(kk,jj+1,ii+1) & |
---|
| 482 | ) / ( 3.0 * gg ) |
---|
| 483 | IF ( kk+1 == nzt+1 ) THEN |
---|
| 484 | w_int = w_int_l |
---|
| 485 | ELSE |
---|
| 486 | w_int_u = ( (gg-aa) * w(kk+1,jj,ii) + (gg-bb) * & |
---|
| 487 | w(kk+1,jj,ii+1) & |
---|
| 488 | + (gg-cc) * w(kk+1,jj+1,ii) + (gg-dd) * & |
---|
| 489 | w(kk+1,jj+1,ii+1) & |
---|
| 490 | ) / ( 3.0 * gg ) |
---|
| 491 | w_int = w_int_l + ( particles(n)%z - zw(kk) ) / dz & |
---|
| 492 | * ( w_int_u - w_int_l ) |
---|
| 493 | ENDIF |
---|
| 494 | |
---|
| 495 | ! |
---|
| 496 | !-- Change in radius due to collision |
---|
| 497 | delta_r = effective_coll_efficiency / 3.0 & |
---|
| 498 | * pi * sl_r3 * ddx * ddy / dz & |
---|
| 499 | * SQRT( ( u_int - particles(n)%speed_x )**2 & |
---|
| 500 | + ( v_int - particles(n)%speed_y )**2 & |
---|
| 501 | + ( w_int - particles(n)%speed_z )**2 & |
---|
| 502 | ) * dt_3d |
---|
| 503 | ! |
---|
| 504 | !-- Change in volume due to collision |
---|
| 505 | delta_v = particles(n)%weight_factor & |
---|
| 506 | * ( ( particles(n)%radius + delta_r )**3 & |
---|
| 507 | - particles(n)%radius**3 ) |
---|
| 508 | |
---|
| 509 | ! |
---|
| 510 | !-- Check if collected particles provide enough LWC for |
---|
| 511 | !-- volume change of collector particle |
---|
| 512 | IF ( delta_v >= sl_r3 .AND. sl_r3 > 0.0 ) THEN |
---|
| 513 | |
---|
| 514 | delta_r = ( ( sl_r3/particles(n)%weight_factor ) & |
---|
| 515 | + particles(n)%radius**3 )**( 1./3. ) & |
---|
| 516 | - particles(n)%radius |
---|
| 517 | |
---|
| 518 | DO is = n-1, psi, -1 |
---|
| 519 | IF ( particles(is)%radius < & |
---|
| 520 | particles(n)%radius ) THEN |
---|
| 521 | particles(is)%weight_factor = 0.0 |
---|
| 522 | particle_mask(is) = .FALSE. |
---|
| 523 | deleted_particles = deleted_particles + 1 |
---|
| 524 | ENDIF |
---|
| 525 | ENDDO |
---|
| 526 | |
---|
| 527 | ELSE IF ( delta_v < sl_r3 .AND. sl_r3 > 0.0 ) THEN |
---|
| 528 | |
---|
| 529 | DO is = n-1, psi, -1 |
---|
| 530 | IF ( particles(is)%radius < particles(n)%radius & |
---|
| 531 | .AND. sl_r3 > 0.0 ) THEN |
---|
| 532 | particles(is)%weight_factor = & |
---|
| 533 | ( ( particles(is)%weight_factor & |
---|
| 534 | * ( particles(is)%radius**3 ) ) & |
---|
| 535 | - ( delta_v & |
---|
| 536 | * particles(is)%weight_factor & |
---|
| 537 | * ( particles(is)%radius**3 ) & |
---|
| 538 | / sl_r3 ) ) & |
---|
| 539 | / ( particles(is)%radius**3 ) |
---|
| 540 | |
---|
| 541 | IF ( particles(is)%weight_factor < 0.0 ) THEN |
---|
| 542 | WRITE( message_string, * ) 'negative ', & |
---|
| 543 | 'weighting factor: ', & |
---|
| 544 | particles(is)%weight_factor |
---|
| 545 | CALL message( 'lpm_droplet_collision', '', & |
---|
| 546 | 2, 2, -1, 6, 1 ) |
---|
| 547 | ENDIF |
---|
| 548 | ENDIF |
---|
| 549 | ENDDO |
---|
| 550 | |
---|
| 551 | ENDIF |
---|
| 552 | |
---|
| 553 | particles(n)%radius = particles(n)%radius + delta_r |
---|
| 554 | ql_vp(k,j,i) = ql_vp(k,j,i) + & |
---|
| 555 | particles(n)%weight_factor * & |
---|
| 556 | ( particles(n)%radius**3 ) |
---|
| 557 | ENDDO |
---|
| 558 | |
---|
| 559 | ENDIF ! collision kernel |
---|
| 560 | |
---|
| 561 | ql_vp(k,j,i) = ql_vp(k,j,i) + particles(psi)%weight_factor & |
---|
| 562 | * particles(psi)%radius**3 |
---|
| 563 | |
---|
| 564 | |
---|
| 565 | ELSE IF ( prt_count(k,j,i) == 1 ) THEN |
---|
| 566 | |
---|
| 567 | psi = prt_start_index(k,j,i) |
---|
| 568 | ql_vp(k,j,i) = particles(psi)%weight_factor * & |
---|
| 569 | particles(psi)%radius**3 |
---|
| 570 | ENDIF |
---|
| 571 | |
---|
| 572 | ! |
---|
| 573 | !-- Check if condensation of LWC was conserved during collision |
---|
| 574 | !-- process |
---|
| 575 | IF ( ql_v(k,j,i) /= 0.0 ) THEN |
---|
| 576 | IF ( ql_vp(k,j,i) / ql_v(k,j,i) >= 1.0001 .OR. & |
---|
| 577 | ql_vp(k,j,i) / ql_v(k,j,i) <= 0.9999 ) THEN |
---|
| 578 | WRITE( message_string, * ) 'LWC is not conserved during',& |
---|
| 579 | ' collision! ', & |
---|
| 580 | 'LWC after condensation: ', & |
---|
| 581 | ql_v(k,j,i), & |
---|
| 582 | ' LWC after collision: ', & |
---|
| 583 | ql_vp(k,j,i) |
---|
| 584 | CALL message( 'lpm_droplet_collision', '', 2, 2, -1, 6, 1 ) |
---|
| 585 | ENDIF |
---|
| 586 | ENDIF |
---|
| 587 | |
---|
| 588 | ENDDO |
---|
| 589 | ENDDO |
---|
| 590 | ENDDO |
---|
| 591 | |
---|
| 592 | CALL cpu_log( log_point_s(43), 'lpm_droplet_coll', 'stop' ) |
---|
| 593 | |
---|
| 594 | |
---|
| 595 | END SUBROUTINE lpm_droplet_collision |
---|