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