Numerical parameters for the wall distance calculation

Collaboration diagram for Numerical parameters for the wall distance calculation:

Variables
integer, save	ineedy
integer, save	imajdy
integer, save	icdpar
	Specifies the method used to calculate the distance to the wall y and the non-dimensional distance for all the cells of the calculation domain (when necessary): More...

Detailed Description

Variable Documentation

icdpar

integer, save icdpar

Specifies the method used to calculate the distance to the wall y and the non-dimensional distance for all the cells of the calculation domain (when necessary):

• 1: standard algorithm (based on a Poisson equation for y and convection equation for ), with reading of the distance to the wall from the restart file if possible
• -1: standard algorithm (based on a Poisson equation for y and convection equation for ), with systematic recalculation of the distance to the wall in case of calculation restart
• 2: former algorithm (based on geometrical considerations), with reading of the distance to the wall from the restart file if possible
  
• -2: former algorithm (based on geometrical considerations) with systematic recalculation of the distance to the wall in case of calculation restart.
  
  In case of restart calculation, if the position of the walls haven’t changed, reading the distance to the wall from the restart file can save a fair amount of CPU time.
  Useful in model with wall echo (iturb=30 and irijec=1), in LES with van Driest damping (iturb=40 and idries=1) and in SST (iturb=60). By default, icdpar is initialised to -1, in case there has been a change in the definition of the boundary conditions between two computations (change in the number or the positions of the walls). Yet, with the SST model, the distance to the wall is needed to calculate the turbulent viscosity, which is done before the calculation of the distance to the wall. Hence, when this model is used (and only in that case), icdpar is set to 1 by default, to ensure total continuity of the calculation at restart. As a consequence, with the SST model, if the number and positions of the walls are changed at a calculation restart, it is mandatory for the user to set icdpar explicitly to -1, otherwise the distance to the wall used will not correspond to the actual position of the walls.
  The former algorithm is not compatible with parallelism nor periodicity. Also, whatever the value chosen for icdpar, the calculation of the distance to the wall is made at the most once for all at the beginning of the calculation; it is therefore not compatible with moving walls. Please contact the development team if you need to override this limitation.

imajdy

integer, save imajdy

• 1, the wall distance is up to date,
  • 0, the wall distance has not been updated.

ineedy

integer, save ineedy

• 1, the wall distance must be computed,
  • 0, the wall distance computation is not necessary.