mus_turbulence_module Module

This module contains data types, function and routines for turbulence model. Especially the routine to compute turbulent eddy viscosity for different turbulence model

author: Kannan Masilamani


Uses


Abstract Interfaces

abstract interface

interface to calculate subgrid scale turbulent eddy viscosity

  • private subroutine proc_calc_turb_visc_fromGradU(turbVisc, turbConfig, gradData, auxField, velPos, nSolve, nAuxScalars, dxL, dtL, Grad)

    This function computes turbulent viscosity from gradient U

    Arguments

    Type IntentOptional Attributes Name
    real(kind=rk), intent(out) :: turbVisc(:)

    output is turbulent viscosity
    type(mus_turbulence_config_type), intent(in) :: turbConfig

    turbulence config contains oefficients
    type(mus_gradData_type), intent(in) :: gradData

    gradient data
    real(kind=rk), intent(in) :: auxField(:)

    Auxiliary field variable array
    integer, intent(in) :: velPos(3)

    position of velocity components in auxField
    integer, intent(in) :: nSolve

    Number of element to solve in this level
    integer, intent(in) :: nAuxScalars

    number of scalars in auxField array
    real(kind=rk), intent(in) :: dxL

    turbulence coefficients current level lattice element size
    real(kind=rk), intent(in) :: dtL

    current level lattice time step size
    type(mus_Grad_type), intent(in) :: Grad

    Object that contains pointers to calculate gradients

abstract interface

interface to calculate subgrid scale turbulent eddy viscosity

  • private subroutine proc_calc_turb_visc_fromPreColPDF(turbVisc, turbConfig, state, neigh, auxField, densPos, velPos, nSize, nSolve, nScalars, nAuxScalars, layout, dxL, dtL, viscKine)

    This function compute turbulent viscosity from pre-collision PDF

    Arguments

    Type IntentOptional Attributes Name
    real(kind=rk), intent(out) :: turbVisc(:)

    output is turbulent viscosity
    type(mus_turbulence_config_type), intent(in) :: turbConfig

    turbulence type is implicitly passed to access turbulence coefficients
    real(kind=rk), intent(in) :: state(:)

    state array
    integer, intent(in) :: neigh(:)

    neigh array to obtain precollision pdf
    real(kind=rk), intent(in) :: auxField(:)

    Auxiliary field variable array
    integer, intent(in) :: densPos

    position of density in auxField
    integer, intent(in) :: velPos(3)

    position of velocity components in auxField
    integer, intent(in) :: nSize

    number of elements in state array
    integer, intent(in) :: nSolve

    Number of element to solve in this level
    integer, intent(in) :: nScalars

    number of scalars in state array
    integer, intent(in) :: nAuxScalars

    number of scalars in auxField array
    type(mus_scheme_layout_type), intent(in) :: layout

    scheme layout
    real(kind=rk), intent(in) :: dxL

    current level lattice element size
    real(kind=rk), intent(in) :: dtL

    current level lattice time step size
    real(kind=rk), intent(in) :: viscKine(:)

    Background kinematic viscosity divided by dtL

Derived Types

type, public ::  mus_turbulence_config_type

Contains turbulence information loaded from config file

Components

Type Visibility Attributes Name Initial
character(len=labelLen), public :: model

turbulence model type
type(les_coeff_type), public :: coeff

les model coefficients
logical, public :: compSR_fromPDF = .false.

To compute strain-rate from non-equilibrium PDF for Smagorinsky les model. If true then velocity and grad data are not required
logical, public :: useKolmogorovScale = .true.

Use Kolmogorov scale for interpolation turbulent viscosity for multilevel

type, public ::  mus_turbulence_data_type

Contains velocity and gradient data to compute eddy viscosity

Components

Type Visibility Attributes Name Initial
type(tem_communication_type), public :: sendBuffer

Communication buffers to communicate visoscity field Local Fluids required by remote processes
type(tem_communication_type), public :: recvBuffer

My halos which are fluids on remote processes
type(tem_communication_type), public :: sendBufferFromCoarser

Local ghostFromCoarser required by remote processes
type(tem_communication_type), public :: sendBufferFromFiner

Local ghostFromFiner required by remote processes
type(tem_communication_type), public :: recvBufferFromCoarser

My halos which are ghostFromCoarser on remote processes
type(tem_communication_type), public :: recvBufferFromFiner

My halos which are ghostFromFiner on remote processes
real(kind=rk), public, allocatable :: visc(:)

Normalized turbulence viscosity i.e. viscosity scaled to current level i.e. visc/dtL Size: nSize (nFluids+nGhosts+nHalos) Used gradData to compute viscosity for nFluids and nGhosts. This viscosity is interpolated and scaled for setting nonEq term interpolation routines. The source element of interpolation might be halo so they are communicated.

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type, public ::  mus_turbulence_type

Contains information required to compute eddy viscosity

Components

Type Visibility Attributes Name Initial
logical, public :: active

is true if turbulence table is defined
type(mus_turbulence_config_type), public :: config

information loaded from config file
type(mus_turbulence_data_type), public, allocatable :: dataOnLvl(:)

contains level-wise turbulence data to compute eddy viscosity size: minlevel:maxLevel
type(mus_turbulence_visc_proc_type), public :: calcVisc

contains turbulence viscosity function pointers
real(kind=rk), public :: fac_c2f

Factor to scale normalized turbulent viscosity from coarse to fine depending on whether useKolmogorovScale true or false if useKolmogorovScale fac_c2f = 1/2^(1/3) else fac_c2f = 1/2 How to use: v^s_f = fac_c2f v^s_c
real(kind=rk), public :: fac_f2c

Factor to scale normalized turbulent viscosity from fine to coarse depending on whether useKolmogorovScale true or false if useKolmogorovScale fac_f2c = 2^(1/3) else fac_f2c = 2 How to use: v^s_c = fac_f2c v^s_f

type, private ::  les_coeff_type

Contains large Eddy Turbulence (LES) model coefficients

Components

Type Visibility Attributes Name Initial
real(kind=rk), public :: C_s

Smagorinsky constant. C_s = sqrt(C_k sqrt(C_k/C_e) ) = 0.16778594 = 0.17
real(kind=rk), public :: C_w

Model constant for WALE (Wall-Adapting Local Eddy-Viscosity) default: 0.5
real(kind=rk), public :: C_v

Model constant for Vreman model In literature: C_v = sqrt(2.5) C_s = 0.27
real(kind=rk), public :: C_e

Modal constant for turbulent kinetic energy dissipation rate default: 1.048
real(kind=rk), public :: C_k

Model constant for eddy-viscosity coefficient default: 0.094_rk https://caefn.com/openfoam/smagorinsky-sgs-model

type, private ::  mus_turbulence_visc_proc_type

Contains function pointers to obtain normalized turbulence viscosity. Viscosity is normalized to current level i.e. v_s = v/dt

Components

Type Visibility Attributes Name Initial
procedure(proc_calc_turb_visc_fromGradU), public, pointer, nopass :: fromGradU => null()

this procedure compute eddy viscosity from velocity field depending turbulence and lbm (compressible/incompressible) models
procedure(proc_calc_turb_visc_fromPreColPDF), public, pointer, nopass :: fromPreColPDF => null()

this procedure compute eddy viscosity from preCollision PDF. It is used for Smagorinsky model which depends only on strain rate that can be calculated using local nonEquilibrium. Is assigned when compSR_fromPDF is .true.

Subroutines

public subroutine mus_load_turbulence(me, conf, parent)

load turbulence table

Arguments

Type IntentOptional Attributes Name
type(mus_turbulence_type), intent(out) :: me

fluid type
type(flu_State) :: conf

lua state
integer, intent(in), optional :: parent

parent handle

public subroutine mus_init_turbulenceData(me, levelDesc, pattern, nSize)

This initialize turbulence data type which includes velocity array and communication buffer

Arguments

Type IntentOptional Attributes Name
type(mus_turbulence_data_type), intent(out) :: me

turbulence data

Read more…
type(tem_levelDesc_type), intent(in) :: levelDesc

levelDesc to access communication buffers of state array
type(tem_commPattern_type), intent(in) :: pattern

communication pattern
integer, intent(in) :: nSize

Number of elements in state array

public subroutine mus_turb_calcVisc(turbData, turbConfig, calcTurbVisc, state, neigh, auxField, gradData, densPos, velPos, nSize, nSolve, nScalars, nAuxScalars, layout, dxL, dtL, viscKine, Grad)

This routine compute turbulence viscosity and stores in turbulence data type

Arguments

Type IntentOptional Attributes Name
type(mus_turbulence_data_type), intent(inout) :: turbData

turbulence data type
type(mus_turbulence_config_type), intent(in) :: turbConfig

turbulence configuration
type(mus_turbulence_visc_proc_type), intent(in) :: calcTurbVisc

turbulence function
real(kind=rk), intent(in) :: state(:)

state array
integer, intent(in) :: neigh(:)

neigh array to obtain precollision pdf
real(kind=rk), intent(in) :: auxField(:)

Auxiliary field variable array
type(mus_gradData_type), intent(in) :: gradData

gradient data
integer, intent(in) :: densPos

position of density in auxField
integer, intent(in) :: velPos(3)

position of velocity components in auxField
integer, intent(in) :: nSize

number of elements in state array
integer, intent(in) :: nSolve

Number of element to solve in this level
integer, intent(in) :: nScalars

number of scalars in state array
integer, intent(in) :: nAuxScalars

number of scalars in auxField array
type(mus_scheme_layout_type), intent(in) :: layout

scheme layout
real(kind=rk), intent(in) :: dxL

lattice element size in current level
real(kind=rk), intent(in) :: dtL

current level lattice time step size
real(kind=rk), intent(in) :: viscKine(:)

Background kinematic viscosity divided by dtL
type(mus_Grad_type), intent(in) :: Grad

Object that contains pointers to calculate gradients

public subroutine mus_turb_updateViscOfTurbWall(turbData, viscTurbWall, nElems_bnd, elemPos)

This routine update turbulent viscosity of boundary elements from RANS viscosity computed in turbulent_wall boundary.

Arguments

Type IntentOptional Attributes Name
type(mus_turbulence_data_type), intent(inout) :: turbData

turbulence data type
real(kind=rk), intent(in) :: viscTurbWall(:)

Turbulent viscosity on turbulent wall boundary computed in set boundary
integer, intent(in) :: nElems_bnd

Number of elements in turbulent_wall boundary
integer, intent(in) :: elemPos(:)

Position of boundary element in levelwise total list or state array