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initialization_parameters

Timestamp:: Sep 16, 2010 2:11:30 PM (14 years ago)
Author:: kanani
Comment:: --

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doc/app/initialization_parameters

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 Horizontal grid spacing along the x-direction (in m).\\\\
 Along x-direction only a constant grid spacing is allowed.\\\\
 For coupled runs (see [[chapter 3.8]]) this parameter must be equal in both parameter files [../iofiles#PARIN PARIN] and [../iofiles#PARIN_O PARIN_O].
+For coupled runs ([../examples/coupled see details]) this parameter must be equal in both parameter files [../iofiles#PARIN PARIN] and [../iofiles#PARIN_O PARIN_O].
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 Horizontal grid spacing along the y-direction (in m).\\\\
 Along y-direction only a constant grid spacing is allowed.\\\\
 For coupled runs (see [[chapter 3.8]]) this parameter must be equal in both parameter files [../iofiles#PARIN PARIN] and [../iofiles#PARIN_O PARIN_O].
+For coupled runs ([../examples/coupled see details]) this parameter must be equal in both parameter files [../iofiles#PARIN PARIN] and [../iofiles#PARIN_O PARIN_O].
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 {{{#!td
 FFT-method to be used.\\\\
 The fast fourier transformation (FFT) is used for solving the perturbation pressure equation with a direct method (see [#psolver psolver]) and for calculating power spectra (see optional software packages, [[chapter 4.2]]).\\\\
+The fast fourier transformation (FFT) is used for solving the perturbation pressure equation with a direct method (see [#psolver psolver]) and for calculating power spectra (see [../packages optional software packages]).\\\\
 By default, system-specific, optimized routines from external vendor libraries are used. However, these are available only on certain computers and there are more or less severe restrictions concerning the number of gridpoints to be used with them.\\\\
 There are two other PALM internal methods available on every machine (their respective source code is part of the PALM source code):\\\\
 …
 Height below which the turbulence signal is used for turbulence recycling (in m).\\\\
 In case of a turbulent inflow (see [#turbulent_inflow turbulent_inflow]), this parameter defines the vertical thickness of the turbulent layer up to which the turbulence extracted at the recycling plane (see [#recycling_width recycling_width]) shall be imposed to the inflow. Above this level the turbulence signal is linearly damped to zero. The transition range within which the signal falls to zero is given by the parameter [#inflow_damping_width inflow_damping_width].\\\\
 By default, this height is set as the height of the convective boundary layer as calculated from a precursor run. See [[chapter 3.9]] about proper settings for getting this CBL height from a precursor run.
+By default, this height is set as the height of the convective boundary layer as calculated from a precursor run. Information about proper settings for getting this CBL height from a precursor run can be found [../examples/turbinf here].
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 The initial (quasi-stationary) turbulence field should be generated by a precursor run and used by setting [#initializing_actions initializing_actions] = '' 'cyclic_fill'.''\\\\
 The distance of the recycling plane from the inflow boundary can be set with parameter [#recycling_width recycling_width]. The heigth above ground above which the turbulence signal is not used for recycling and the width of the layer within the magnitude of the turbulence signal is damped from 100% to 0% can be set with parameters [#inflow_damping_height inflow_damping_height] and [#inflow_damping_width inflow_damping_width].\\\\
 The detailed setup for a turbulent inflow is described in [[chapter 3.9]].
+The detailed setup for a turbulent inflow is described in [../examples/turbinf here].
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 By default, the near-surface subgrid-scale fluxes are parameterized (like in the remaining model domain) using the gradient approach. If '''use_surface_fluxes''' = ''.T.,'' the user-assigned surface fluxes are used instead (see [#surface_heatflux surface_heatflux], [#surface_waterflux surface_waterflux] and [#surface_scalarflux surface_scalarflux]) or the surface fluxes are calculated via the Prandtl layer relation (depends on the bottom boundary conditions, see [#bc_pt_b bc_pt_b], [#bc_q_b bc_q_b] and [#bc_s_b bc_s_b]).\\\\
 '''use_surface_fluxes''' is automatically set ''.T.,'' if a Prandtl layer is used (see [#prandtl_layer prandtl_layer]).\\\\
 The user may prescribe the surface fluxes at the bottom boundary without using a Prandtl layer by setting '''use_surface_fluxes''' = ''.T.'' and [#prandtl_layer prandtl_layer] = ''.F.''. If , in this case, the momentum flux (u,,*,,^2^) should also be prescribed, the user must assign an appropriate value within the user-defined code (see [[chapter 3.5]]).
+The user may prescribe the surface fluxes at the bottom boundary without using a Prandtl layer by setting '''use_surface_fluxes''' = ''.T.'' and [#prandtl_layer prandtl_layer] = ''.F.''. If , in this case, the momentum flux (u,,*,,^2^) should also be prescribed, the user must assign an appropriate value within the [../userint user-defined code].
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       The arrays of the 3d-model are initialized with the (stationary) solution of the [../../tec/1dmodel 1d-model]. These are the variables e, K,,h,,{{{,}}} K,,m,,{{{,}}} u, v and with Prandtl layer switched on rif, us, usws, vsws. The temperature (humidity) profile consisting of linear sections is set as for '' 'set_constant_profiles' '' and assumed as constant in time within the 1d-model. For steering of the 1d-model a set of parameters with suffix "_1d" (e.g. [#end_time_1d end_time_1d], [#damp_level_1d damp_level_1d]) is available.\\\\
 '' 'by_user' ''\\\\
       The initialization of the arrays of the 3d-model is under complete control of the user and has to be done in routine {{{user_init_3d_model}}} of the user-interface (see [[section 3.5.1]]).\\\\
+      The initialization of the arrays of the 3d-model is under complete control of the user and has to be done in routine {{{user_init_3d_model}}} of the [../userint user-interface].\\\\
 '' 'initialize_vortex' ''\\\\
       The initial velocity field of the 3d-model corresponds to a Rankine-vortex with vertical axis. This setting may be used to test advection schemes. Free-slip boundary conditions for u and v (see [#bc_uv_b bc_uv_b], [#bc_uv_t bc_uv_t]) are necessary. In order not to distort the vortex, an initial horizontal wind profile constant with height is necessary (to be set by [#initializing_actions initializing_actions] = '' 'set_constant_profiles{{{'}}}'') and some other conditions have to be met (neutral stratification, diffusion must be switched off, see [#km_constant km_constant]). The center of the vortex is located at jc = ([#nx nx]+1)/2. It extends from k = 0 to k = [#nz nz]+1. Its radius is 8 * [#dx dx] and the exponentially decaying part ranges to 32 * dx (see {{{init_rankine.f90}}}).\\\\
 …
       A 2d-Gauss-like shape disturbance (x,y) is added to the initial temperature field with radius 10.0 * [#dx dx] and center at jc = ([#nx nx]+1)/2. This may be used for tests of scalar advection schemes (see [#scalar_advec scalar_advec]). Such tests require a horizontal wind profile constant with hight and diffusion switched off (see '' 'initialize_vortex' ''). Additionally, the buoyancy term must be switched of in the equation of motion  for w (this requires the user to comment out the call of buoyancy in the source code of {{{prognostic_equations.f90}}}).\\\\
 '' 'cyclic_fill' ''\\\\
       Here, 3d-data from a precursor run are read by the initial (main) run. The precursor run is allowed to have a smaller domain along x and y compared with the main run. Also, different numbers of processors can be used for these two runs. Limitations are that the precursor run must use cyclic horizontal boundary conditions and that the number of vertical grid points, [#nz nz], must be same for the precursor run and the main run. If the total domain of the main run is larger than that of the precursor run, the domain is filled by cyclic repetition of the (cyclic) precursor data. This initialization method is recommended if a turbulent inflow is used (see [#turbulent_inflow turbulent_inflow]). 3d-data must be made available to the run by activating an appropriate file connection statement for local file [../iofiles#BININ BININ]. See [[chapter 3.9]] for more details, where usage of a turbulent inflow is explained.\\\\
+      Here, 3d-data from a precursor run are read by the initial (main) run. The precursor run is allowed to have a smaller domain along x and y compared with the main run. Also, different numbers of processors can be used for these two runs. Limitations are that the precursor run must use cyclic horizontal boundary conditions and that the number of vertical grid points, [#nz nz], must be same for the precursor run and the main run. If the total domain of the main run is larger than that of the precursor run, the domain is filled by cyclic repetition of the (cyclic) precursor data. This initialization method is recommended if a turbulent inflow is used (see [#turbulent_inflow turbulent_inflow]). 3d-data must be made available to the run by activating an appropriate file connection statement for local file [../iofiles#BININ BININ]. The usage of a turbulent inflow is explained [../examples/turbinf here].\\\\
 Values may be combined, e.g. '''initializing_actions''' = '' 'set_constant_profiles initialize_vortex' '', but the values of '' 'set_constant_profiles' '', '' 'set_1d-model_profiles' '' , and '' 'by_user' '' must not be given at the same time.
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 By means of '''alpha_surface''' the model domain can be inclined in x-direction with respect to the horizontal. In this way flows over inclined surfaces (e.g. drainage flows, gravity flows) can be simulated. In case of '''alpha_surface''' /= ''0'' the buoyancy term appears both in the equation of motion of the u-component and of the w-component.\\\\
 An inclination is only possible in case of cyclic horizontal boundary conditions along x '''AND''' y (see [#bc_lr bc_lr] and [#bc_ns bc_ns]) and [#topography topography] = '' 'flat'.''\\\\
 Runs with inclined surface still require additional user-defined code (see [[chapter 3.5]]) as well as modifications to the default code. Please ask the PALM developer group.
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+Runs with inclined surface still require additional [../userint user-defined code] as well as modifications to the default code. Please ask the PALM developer group ([[contact details]]).
+}}}