| | 1 | == Overview == |
| | 2 | |
| | 3 | [[NoteBox(note,This page is part of the **Chemical Model** (CHEM) documentation. \\ It contains a listing of the output steering. \\ For an overview of all CHEM-related pages\, see the **[wiki:doc/tec/chem CHEM main page]**.)]] |
| | 4 | |
| | 5 | == Chemistry mechanism == |
| | 6 | Currently PALM-4U includes the following sample of chemistry mechanisms:\\ |
| | 7 | * cbm4: Carbon Bond Mechanism (Gery et al. (1989), 32 compounds, 81 reactions)\\ |
| | 8 | * smog: Photochemical smog mechanism (13 compounds, 12 reactions)\\ |
| | 9 | * simple: Simplified version of SMOG (9 compounds, 7 reactions)\\ |
| | 10 | * simplep: 'simple' plus one tracer named PM10 (10 compounds, 7 real reactions plus one dummy 'reaction')\\ |
| | 11 | * phstat: Photo-stationary state (3 compounds, 2 reactions)\\ |
| | 12 | * phstatp: Photo-stationary state plus one passive tracer named PM10 (4 compounds, 2 real reactions plus one dummy 'reaction')\\ |
| | 13 | |
| | 14 | Additional 'mechanisms' are available that describe the transport of one or two passive tracers, i.e. no chemical reactions are necessary:\\ |
| | 15 | * passive1: Passive tracers (1 compound, 0 reactions)\\ |
| | 16 | * passive: Passive tracers (2 compounds, 0 reactions)\\ |
| | 17 | This list will be extended further in the future. |
| | 18 | |
| | 19 | The standard mechanism which is in the SOURCE directory is 'phstatp'. |
| | 20 | |
| | 21 | In order to select and apply a certain mechanism from this sample, please copy the respective ready-to-use `chem_gasephase_mod.f90` from `UTIL/chemistry/gasphase_preproc/mechanisms/def_MECH` (where `MECH` stands for any of the available mechanisms) into the USER_CODE directory of the respective simulation Setup, i.e. .../JOBS/<run_identifier>/USER_CODE/chem_gasphase_mod.f90. |
| | 22 | |
| | 23 | Alternatively, the chemistry preprocessor can be executed also for the available machanism in order to create `chem_gasphase_mod.f90` (although for the available mechanisms this is not necessary because the `chem_gasphase_mod.f90` files are already existing) instead of copying `chem_gasphase_mod.f90`: Enter the directory `UTIL/chemistry/gasphase_preproc` and apply the run script, i.e. {{{run_kpp4palm.ksh -m MECH}}}, where `MECH` stands for any of the mechanisms listed above. The resulting `chem_gasphase_mod.f90` will be copied by the script directly into the SOURCE directory. |
| | 24 | |
| | 25 | In order to find out which reactions and compounds are included in the different mechanisms, please have a look into the files MECH.eqn and MECH.spc in `UTIL/chemistry/gasphase_preproc/mechanisms/def_MECH`. |
| | 26 | |
| | 27 | How to implement a new chemical mechanism or add further passive tracers see the [wiki:chempar#no1 Readme-File]. If more than two passive tracers or different names of the passive tracers are desired, a new 'mechanism' must be created as described in the Readme file. The Readme file is also available in the PALM-4U subdirectory `UTIL/chemistry/gasphase_preproc`. |
