14.8. The Sand-Grain Roughness Distribution File (roughness.dat)

This file provides the mechanism to impose equivalent sand-grain roughness values on surface nodes, similar to the timebc.dat file of The timebc.dat file, and is used only if the Variable roughness mode is enabled. The format is as follows:

 
 1 1 1 
 1 nmbr_bc_conds nmbr_bc_conds 
 nodeid 20 value [domain_nmbr] 
 nodeid 20 value [domain_nmbr] 
 nodeid 20 value [domain_nmbr] 
 ...... .. ..... ........... 
 ...... .. ..... ........... 
 ...... .. ..... ........... 

where:

  • nmbr_bc_conds

Number of boundary conditions to impose at the current time level (32-bit integer)
  • nodeid

Node number (32-bit integer)
  • 20

ID number of the roughness variable (32-bit integer)
  • value

Equivalent sand-grain roughness height (m) (64-bit double-precision)
  • domain

Number of the grid domain, grid stitching mode only (32-bit integer). It can be omitted if only a single domain is present.

Note:  For information on the CFD-Post View Setup File for FENSAP-ICE, see View Set-up File.