setTurbulenceFields

Overview

The setTurbulenceFields utility applies a two-step automatic initialisation procedure for RAS computations based on the work of Manceau45 to address slow or non-convergence attributed in the first O(10) time steps and improve resulting predictions.

Usage

Synopsis

setTurbulenceFields [OPTIONS]

Examples

setTurbulenceFields -region region1

Input

Arguments

No arguments required.

Options

-case <dir>       Case directory (instead of current directory)
  -decomposeParDict <file>
                    Alternative decomposePar dictionary file
  -dict <file>      Alternative setTurbulenceFieldsDict
  -parallel         Run in parallel
  -region <name>    Specify mesh region (default: region0)
  -doc              Display documentation in browser
  -help             Display short help and exit
  -help-compat      Display compatibility options and exit
  -help-full        Display full help and exit

Files

The setTurbulenceFields utility is configured using a <case>/system/setTurbulenceFieldsDict, taking the form:

// Mandatory entries
uRef            17.55;


// Optional entries
initialiseU     true;
initialiseEpsilon true;
initialiseK     true;
initialiseOmega true;
initialiseR     true;
writeF          true;

kappa           0.41;
Cmu             0.09;
dPlusRef        15.0;

f               f;
U               U;
epsilon         epsilon;
k               k;
omega           omega;
R               R;

Property	Description	Type	Required	Default
uRef	Reference speed	scalar	yes	-
initialiseU	Flag to initialise U	bool	no	false
initialiseEpsilon	Flag to initialise epsilon	bool	no	false
initialiseK	Flag to initialise k	bool	no	false
initialiseOmega	Flag to initialise omega	bool	no	false
initialiseR	Flag to initialise R	bool	no	false
writeF	Flag to write elliptic-blending field, f	bool	no	false
kappa	von Karman constant	scalar	no	0.41
Cmu	Empirical constant	scalar	no	0.09
dPlusRef	Reference dPlus	scalar	no	15
f	Name of operand f field	word	no	f
U	Name of operand U field	word	no	U
epsilon	Name of operand epsilon field	word	no	epsilon
k	Name of operand k field	word	no	k
omega	Name of operand omega field	word	no	omega
R	Name of operand R field	word	no	R

• Time that the utility applies to is determined by the startFrom and startTime entries of the controlDict.
• The utility modifies near-wall fields, hence can be more effective for low-Re mesh cases.

Fields

No field input required.

Output

Logs

No log output.

Files

No file output.

Fields

Property	Description	Path	Type
U	Velocity	<case>/<time>/	volVectorField
nut	Turbulence viscosity	<case>/<time>/	volScalarField
epsilon	Turbulence kinetic energy dissipation rate	<case>/<time>/	volScalarField
k	Turbulence kinetic energy	<case>/<time>/	volScalarField
omega	Specific dissipation rate	<case>/<time>/	volScalarField
R	Reynolds stress tensor	<case>/<time>/	volSymmScalarField
f	Elliptic blending factor	<case>/<time>/	volScalarField

Method

Equations 3, 6, 8-13 and page 2 of Manceau45.

Further information

Tutorial:

• planeChannel

Source code:

• setTurbulenceFields

History: Introduced in version v2206