Changes between Version 108 and Version 109 of doc/app/particle_parameters

Timestamp:

Sep 14, 2010 8:50:19 AM (14 years ago)

Author:

suehring

Comment:

--

doc/app/particle_parameters

@@ -20 +20 @@
 By default, particles are weightless and transported passively with the resolved scale flow. Particles can be given a mass and thus an inertia by assigning the package parameter density_ratio a non-zero value (it defines the ratio of the density of the fluid and the density of the particles). In these cases their radius must also be defined, which affects their flow resistance. \\\\
 Boundary conditions for the particle transport can be defined with package parameters [#bc_par_t bc_par_t], [#bc_par_lr bc_par_lr], [#bc_par_ns bc_par_ns] and [#bc_par_b bc_par_b].\\\\
-Timeseries of particle quantities in netCDF format can be output to local file [../iofile#DATA_1D_PTS_NETCDF DATA_1D_PTS_NETCDF] by using package parameter [#dt_dopts dt_dopts].\\\\
-For analysis, additional output of particle information in equidistant temporal intervals can be carried out using [#dt_write_particle_data dt_write_particle_data] (file [../iofile#PARTICLE_DATA PARTICLE_DATA]).\\\\
-Statistical informations (e.g. the total number of particles used, the number of particles exchanged between the PEs, etc.) are output to the local file [../iofile#PARTICLE_INFOS PARTICLE_INFOS], if switched on by the parameter [#write_particle_statistics write_particle_statistics]. \\\\
-If a job chain is to be carried out, particle informations for the restart run (e.g. current location of all particles at the end of the run) is output to the local file [../iofile#PARTICLE_RESTART_DATA_OUT PARTICLE_RESTART_DATA_OUT], which must be saved at the end of the run and given as an input file to the restart run under local file name [../iofile#PARTICLE_RESTART_DATA_IN PARTICLE_RESTART_DATA_IN] using respective file connection statements in the '''mrun''' configuration file. \\\\
+Timeseries of particle quantities in netCDF format can be output to local file [../iofiles#DATA_1D_PTS_NETCDF DATA_1D_PTS_NETCDF] by using package parameter [#dt_dopts dt_dopts].\\\\
+For analysis, additional output of particle information in equidistant temporal intervals can be carried out using [#dt_write_particle_data dt_write_particle_data] (file [../iofiles#PARTICLE_DATA PARTICLE_DATA]).\\\\
+Statistical informations (e.g. the total number of particles used, the number of particles exchanged between the PEs, etc.) are output to the local file [../iofiles#PARTICLE_INFOS PARTICLE_INFOS], if switched on by the parameter [#write_particle_statistics write_particle_statistics]. \\\\
+If a job chain is to be carried out, particle informations for the restart run (e.g. current location of all particles at the end of the run) is output to the local file [../iofiles#PARTICLE_RESTART_DATA_OUT PARTICLE_RESTART_DATA_OUT], which must be saved at the end of the run and given as an input file to the restart run under local file name [../iofiles#PARTICLE_RESTART_DATA_IN PARTICLE_RESTART_DATA_IN] using respective file connection statements in the '''mrun''' configuration file. \\\\
 The output of particles for visualization with the graphic software '''dvrp''' is steered by the package parameter [../dvrpar#dt_dvrp dt_dvrp]. For visualization purposes particles can be given a diameter using the parameters [../dvrpar#dvrp_psize dvrp_psize] and [../dvrpar#particle_dvrpsize particle_dvrpsize] (this diameter only affects the visualization). All particles have the same size. Alternatively, particles can be given an individual size and a color by modifying the user-interface (subroutine {{{user_init_particles}}}). Particles can pull a ''tail'' behind themselves to improve their visualization. This is steered via the parameter [#use_particle_tails use_particle_tails].\\\\
 '''So far, the particle transport realized in PALM does only work duly in case of a constant vertical grid spacing! '''
@@ -175 +175 @@
 {{{#!td
 Temporal interval for sorting particles (in s).\\
-By default, particles are sorted in memory in a way that their order follows the order in which the gridpoint values are stored. This may improve cache coherence in case of larger numbers of particles and gridpoints. However, since the sorting itself is time consuming and since the requirement of sorting depends on the strength of mixing in the flow, performance can be improved if the sorting is applied only after certain time intervals. The proper length of this interval '''dt_sort_particles''' must be determined empirically by carrying out test runs with different intervals. Check file [../iofile#CPU_MEASURES CPU_MEASURES] to find the value of '''dt_sort_particles''' which gives the best performance.\\\\
+By default, particles are sorted in memory in a way that their order follows the order in which the gridpoint values are stored. This may improve cache coherence in case of larger numbers of particles and gridpoints. However, since the sorting itself is time consuming and since the requirement of sorting depends on the strength of mixing in the flow, performance can be improved if the sorting is applied only after certain time intervals. The proper length of this interval '''dt_sort_particles''' must be determined empirically by carrying out test runs with different intervals. Check file [../iofiles#CPU_MEASURES CPU_MEASURES] to find the value of '''dt_sort_particles''' which gives the best performance.\\\\
 '''Note:''' In case of [../inipar#cloud_droplets cloud_droplets] = '' '.T.' '', any given non-zero value of '''dt_sort_particles''' will be reset to zero and a corresponding warning message will appear in the job protocol.
 }}}
@@ -190 +190 @@
 {{{#!td
 Temporal interval for output of particle data (in s).\\
-This parameter can be used to assign the temporal interval at which particle data shall be output. Data are output to the local file [../iofile#PARTICLE_DATA PARTICLE_DATA]. See the file description for more details about its format.\\
+This parameter can be used to assign the temporal interval at which particle data shall be output. Data are output to the local file [../iofiles#PARTICLE_DATA PARTICLE_DATA]. See the file description for more details about its format.\\
 By default, no particle data are output.
 }}}
@@ -503 +503 @@
 {{{#!td
 Read particle data from the previous run. \\
-By default, with restart runs particle data is read from file [../iofile#PARTICLE_RESTART_DATA_IN PARTICLE_RESTART_DATA_IN], which is created by the preceding run. If this is not requested or if in a restart run particle transport is switched on for the first time (see [#particle_advection_start particle_advection_start]), then '''read_particles_from_restartfile''' = ''.F.'' is required.
+By default, with restart runs particle data is read from file [../iofiles#PARTICLE_RESTART_DATA_IN PARTICLE_RESTART_DATA_IN], which is created by the preceding run. If this is not requested or if in a restart run particle transport is switched on for the first time (see [#particle_advection_start particle_advection_start]), then '''read_particles_from_restartfile''' = ''.F.'' is required.
 }}}
 |----------------
@@ -577 +577 @@
 {{{#!td
 Switch on/off output of particle informations.\\
-For '''write_particle_statistics''' = ''.T.'' statistical informations (e.g. the total number of particles used, the number of particles exchanged between the PEs, etc.) which may be used for debugging are output to the local file [../iofile#PARTICLE_INFOS PARTICLE_INFOS]. \\\\
+For '''write_particle_statistics''' = ''.T.'' statistical informations (e.g. the total number of particles used, the number of particles exchanged between the PEs, etc.) which may be used for debugging are output to the local file [../iofiles#PARTICLE_INFOS PARTICLE_INFOS]. \\\\
 '''Note:''' For parallel runs files may become very large and performance of PALM may decrease.
 }}}