Changes between Version 20 and Version 21 of doc/tec/nesting

Timestamp:

Nov 23, 2018 10:03:14 AM (6 years ago)

Author:

suehring

Comment:

--

doc/tec/nesting

@@ -6 +6 @@
 The nesting within larger-scale models is hence referred to as offline nesting. 
 Both nesting systems can be used at the same time, which allows to resolve small-scale phenomena without neglecting larger-scale processes on the synoptic scale.  
-The documentation contains several sections:
+The following sections contain a documentation of the PALM self nesting as well as of the offline nesting in larger-scales models, which include a general description of the method, the required input parameters, preparatory steps, as well as example setups. 
+Please click on any icon below to get to the respective part of the documentation.\\\\
+
+'''PALM self nesting'''
 
 ...
+
+[[Image(button_input.png,120px,link=wiki:doc/app/agtpar)]] 
+[[Image(button_ex_setup.png,120px,link=browser:palm/trunk/EXAMPLES/agents/)]] 
+[[Image(button_prepro.png,120px,link=wiki:doc/tec/mas/agent_preprocessing)]] 
+[[Image(button_a_star.png,120px,link=wiki:doc/tec/mas/agent_pathfinding)]] 
+[[Image(button_social_force.png,120px,link=wiki:doc/tec/mas/social_forces)]] 
+[[Image(button_output.png,120px,link=wiki:doc/tec/mas/output)]]
+[[Image(button_code_structure.png,120px,link=wiki:doc/tec/mas/implementation)]]  \\\\\\\\   
+[[Image(pathfinding_berlin.gif,600)]]
+
+ Input:: List of all namelist parameters \\\\
+ Preparatory steps:: Description how to prepare the config file for a nested setup \\\\
+ Example setup:: Files to carry out example runs \\\\
+
+
+
+
+
+'''Offline nesting within larger-scale models'''
+
+Since revision -r3347 a nesting in larger-scale models is available in PALM, which is realized as a pure offline nesting. 
+Therefore, time-dependent values for the three velocity components, potential temperature and the mixing ratio are stored for the lateral and top boundaries of the PALM model domain in the dynamic input file (see [wiki:doc/app/iofiles/pids/#dynamic_input dynamic input file]). 
+The boundary data are read and mapped onto the respective boundaries during the simulation, while the boundary data is interpolated linearly in time, depending on the data availability. 
+This way, it is possible to account for changing synoptic conditions during the simulation without adding further tendency terms or to nudge the LES solution. 
+The four lateral boundaries as well as the model top boundary are thus non-cyclic boundaries (see [wiki:doc/tec/bc#noncyc non-cyclic]), where, depending on the input data, in- and outflow can occur simultaneously at one lateral boundary layer. 
+At the beginning, the model is initialized with mean profiles or heterogeneous 3D data inferred from the larger-scale model. \\\\
+
+The PALM model can be nested into any larger-scale model of your choice (COSMO, WRF, etc.), subject to the condition that the data in the dynamic input file is readable, i.e. with horizontal and vertical dimensions as expected by PALM. 
+Boundary data need to be provided for each boundary grid point at the lateral ''xz, yz''-layers as well as at the top boundary.  
+To date, the pre-processing tool [wiki:doc/app/iofiles/inifor INIFOR] is available which can convert output data from the COSMO model into PALM-readable boundary data (not available for WRF so far).  \\\\
+
+Larger-scale model output data do not encompass any resolved-scale turbulence but turbulence is completely parametrized. 
+Hence, turbulence needs to develop first in the PALM model domain, requiring some adjustment zones near the boundaries.  
+In order reduce the adjustment zones near the boundaries, turbulence development is accelerated / triggered by using a [wiki:doc/tec/bc#synth synthetic turbulence generator], which is applied at the lateral boundaries; and imposes turbulent fluctuations onto the boundary data of the velocity components with characteristic amplitude depending on atmospheric stability inferred from the mean boundary data.  \\\\
+
+The offline nesting can be applied in combination with the self nesting implemented in PALM, with the root model nested offline in the larger-scale model and the child models recursively nesting within the root model.  
+This case, only the root model requires the initialization and boundary data from the larger-scale model via the [wiki:doc/app/iofiles/pids/#dynamic_input dynamic input file]. 
+
+To apply the offline nesting, a [wiki:doc/app/iofiles/pids/#dynamic_input dynamic input file] is required, as well as the namelist [wiki:doc/app/nestofflpar#nestofflpars &nesting_offl_parameters] must be provided.
+
+[[Image(button_input.png,120px,link=wiki:doc/app/agtpar)]] 
+[[Image(button_ex_setup.png,120px,link=browser:palm/trunk/EXAMPLES/agents/)]] 
+[[Image(button_prepro.png,120px,link=wiki:doc/tec/mas/agent_preprocessing)]] 
+[[Image(button_a_star.png,120px,link=wiki:doc/tec/mas/agent_pathfinding)]] 
+[[Image(button_social_force.png,120px,link=wiki:doc/tec/mas/social_forces)]] 
+[[Image(button_output.png,120px,link=wiki:doc/tec/mas/output)]]
+[[Image(button_code_structure.png,120px,link=wiki:doc/tec/mas/implementation)]]  \\\\\\\\   
+[[Image(pathfinding_berlin.gif,600)]]
+
+ Input:: List of all namelist parameters \\\\
+ Preparatory steps:: Description how to prepare the config file for a nested setup \\\\
+ Example setup:: Files to carry out example runs \\\\
+
+
 
 A multi-scale nesting system is available since r1763. It currently undergoes major testing and revisions. A detailed description will follow after the official release.