A Note on Differencing the Viscous Dissipation Terms for a Newtonian Fluid

Cloutman, L

Lawrence Livermore National Laboratory

关键词: Transport;    42 Engineering;    Viscosity;    Turbulence;    Velocity;   

DOI  :  10.2172/15005563
RP-ID  :  UCRL-ID-144159
RP-ID  :  W-7405-ENG-48
RP-ID  :  15005563

美国|英语

来源: UNT Digital Library

【 摘 要 】

We compare two finite difference approximations for the viscous dissipation terms in the energy equation. We focus on the strain produced by the every-other-zone (e.g., hour-glass and herringbone) modes in the velocity field. Care must be exercised to produce a viscous dissipation rate consistent with the viscous forces. The examples given are for a rectangular staggered grid, but similar considerations apply to other types of grids. Also, these considerations apply to certain algebraic eddy viscosity models and to the shear creation terms in turbulence transport models.