/MAT/LAW46 (LES_FLUID)
Block Format Keyword Describes the viscous fluid material with sub-grid scale viscosity.
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
/MAT/LAW46/mat_ID/unit_ID or /MAT/LES_FLUID/mat_ID/unit_ID | |||||||||
mat_title | |||||||||
ρi | ρ0 | ||||||||
c | ν | ||||||||
Isgs | Cs | Csp |
Definition
Field | Contents | SI Unit Example |
---|---|---|
mat_ID | Material identifier. (Integer, maximum 10 digits) |
|
mat_title | Material
title. (Character, maximum 100 characters) |
|
unit_ID | Unit Identifier. (Interger, maximum 10 digits) |
|
ρi | Initial
density. (Real) |
[kgm3] |
ρ0 | Reference density
used in E.O.S (equation of state). Default ρ0=ρi (Real) |
[kgm3] |
c | Speed of
sound. (Real) |
[ms] |
ν | Molecular kinematic
viscosity. (Real) |
[m2s] |
Isgs | Sub-grid scale model.
(Integer) |
|
Cs | Smagorinsky
constant. Default = 0.1 (Real) |
|
Csp | Pressure damping
coefficient. Default = Cs (Real) |
[1s] |
▸Example (Fluid)
Comments
- For Isgs = 1 or 2, Δ=3√Volume .
- For Isgs = 3, Δ is the smallest dimension of each element.
-
νsgs
is computed as:
(1) νsgs=(CsΔ)2(eij)12 - This law is modified
near wall boundaries:
ν+νsgs=ν⋅k⋅y+2ln(Ey+2) if y+2≥11.225
νsgs=0 , otherwise.
Where,- νsgs
- Sub grid scale viscosity
- k
- von Kahrman constant