Changes between Version 24 and Version 25 of doc/app/examples/turbinf

Timestamp:

Dec 5, 2019 10:05:36 AM (5 years ago)

Author:

oliver.maas

Comment:

--

doc/app/examples/turbinf

@@ -23 +23 @@
   * Set options for turbulent inflow in the parameter file of the main run
 
-    For initialization it has to be set [../../inipar#initializing_actions initializing_actions] = '' 'cyclic_fill' ''.
+    For initialization set [../../inipar#initializing_actions initializing_actions] = '' 'cyclic_fill' ''. Note that the initial flow field has a perfectly regular structure with a periodicity of the precursor run. This regularity can persist for a very long time. To break up this regularity, use a domain width that is not an integer multiple of the precursor run domain width. The occurring flow field discontinuity at the lateral domain boundary initiates a fast break up of the regularity.
 
     Horizontal boundary conditions have to be set to [../../inipar#bc_lr bc_lr] = '' 'dirichlet/radiation' ''. '''The radiation boundary condition at the outflow requires that the wall-normal velocity component at the outflow must point out of the domain at every grid point and at every timestep.''' Special care has to be taken in case of obstacles near the outflow, because their recirculations may violate this condition.
@@ -37 +37 @@
     A damping layer for the turbulence signal can be set at top of the domain via [../../inipar#inflow_damping_height inflow_damping_height] and [../../inipar#inflow_damping_width inflow_damping_width]. Inside the damping layer the turbulence signal is linearly damped to 0%. For [../../inipar#inflow_damping_height inflow_damping_height] the boundary layer height from the precursor run should be used.
 
-    The recycled turbulence, which is mapped from the recycling plane to the inflow boundary, can be shifted in y direction. This y-shift reduces persistent streaks that may occur within the recycling domain. To use the y-shift set [../../initialization_parameters#y_shift y_shift] to a non-zero value. The distance of the y-shift is given in number of processors (PE) and should be roughly equal to the boundary layer height. For an effective reduction of streaks it is important that the flow passes the domain many times until it is shifted to its initial y-position. The number of flowthroughs is given by the least common multiple of y_shift and [../../initialization_parameters#npey npey] divided by y_shift. For further details refer to Munters (2016; ​http://www.dx.doi.org/10.1063/1.4941912).
+    The recycled turbulence, which is mapped from the recycling plane to the inflow boundary, can be shifted in y direction. This y-shift reduces persistent streaks that may occur within the recycling domain. To use the y-shift set [../../initialization_parameters#y_shift y_shift] to a non-zero value. The distance of the y-shift is given in number of processors (PE) and should be roughly equal to the boundary layer height. For an effective reduction of streaks it is important that the flow passes the domain many times until it is shifted to its initial y-position. The number of flowthroughs is given by the least common multiple of y_shift and [../../initialization_parameters#npey npey] divided by y_shift. Note that this is only true for a perfectly x-aligned flow. For further details refer to Munters (2016; ​http://www.dx.doi.org/10.1063/1.4941912).
 
   * When starting the main run, [wiki:doc/app/palmrun palmrun] must be told to provide the binary data of the restart run which is done by adding 'rec' to the activation-string list of the palmrun command (option {{{-a}}}, see job control with [wiki:doc/app/palmrun palmrun]).