cs_user_physical_properties.f90 File Reference

Definition of physical variable laws. More...

Functions/Subroutines
subroutine	usphyv (nvar, nscal, mbrom, dt)
	Definition of physical variable laws. More...
subroutine	usvist (nvar, nscal, ncepdp, ncesmp, icepdc, icetsm, itypsm, dt, ckupdc, smacel)
	Modify turbulent viscosity. More...
subroutine	ussmag (nvar, nscal, ncepdp, ncesmp, icepdc, icetsm, itypsm, dt, ckupdc, smacel, mijlij, mijmij)
	user modification of the Smagorinsky constant in the case of a dynamic model More...

Detailed Description

Definition of physical variable laws.

See Define user laws for physical properties for examples.

Function/Subroutine Documentation

usphyv()

subroutine usphyv	(	integer	nvar,
		integer	nscal,
		integer	mbrom,
		double precision, dimension(ncelet)	dt
	)

Definition of physical variable laws.

Warning

It is forbidden to modify turbulent viscosity visct here (a specific subroutine is dedicated to that: usvist)

• icp = 0 must have been specified in usipsu if we wish to define a variable specific heat cpro_cp (otherwise: memory overwrite).
• the kivisl field integer key (diffusivity_id) must have been specified in usipsu if we wish to define a variable viscosity viscls.

Remarks

• This routine is called at the beginning of each time step Thus, AT THE FIRST TIME STEP (non-restart case), the only values initialized before this call are those defined
  • in the GUI or usipsu (cs_user_parameters.f90)
    • density (initialized at ro0)
    • viscosity (initialized at viscl0)
  • in the GUI or cs_user_initialization
    • calculation variables (initialized at 0 by defaut or to the value given in the GUI or in cs_user_initialization)
• We may define here variation laws for cell properties, for:
  • density: rom kg/m3
  • density at boundary faces: romb kg/m3)
  • molecular viscosity: cpro_viscl kg/(m s)
  • specific heat: cpro_cp J/(kg degrees)
  • diffusivities associated with scalars: cpro_vscalt kg/(m s)

Warning: if the scalar is the temperature, cpro_vscalt corresponds to its conductivity (Lambda) in W/(m K)

The types of boundary faces at the previous time step are available (except at the first time step, where arrays itypfb and itrifb have not been initialized yet)

It is recommended to keep only the minimum necessary in this file (i.e. remove all unused example code)

Cells identification

Cells may be identified using the getcel subroutine. The syntax of this subroutine is described in the cs_user_boundary_conditions subroutine, but a more thorough description can be found in the user guide.

Parameters

[in]	nvar	total number of variables
[in]	nscal	total number of scalars
[in]	mbrom	indicator of filling of romb array
[in]	dt	time step (per cell)

ussmag()

subroutine ussmag	(	integer	nvar,
		integer	nscal,
		integer	ncepdp,
		integer	ncesmp,
		integer, dimension(ncepdp)	icepdc,
		integer, dimension(ncesmp)	icetsm,
		integer, dimension(ncesmp,nvar)	itypsm,
		double precision, dimension(ncelet)	dt,
		double precision, dimension(6,ncepdp)	ckupdc,
		double precision, dimension(ncesmp,nvar)	smacel,
		double precision, dimension(ncelet)	mijlij,
		double precision, dimension(ncelet)	mijmij
	)

user modification of the Smagorinsky constant in the case of a dynamic model

SMAGOR = Mij.Lij / Mij.Mij

The local averages of the numerator and denominator are done before calling this subroutine, so

         SMAGOR = < Mij.Lij > / < Mij.Mij >

In this subroutine, Mij.Lij and Mij.Mij are passed as arguments before the local average.

Parameters

[in]	nvar	total number of variables
[in]	nscal	total number of scalars
[in]	ncepdp	number of cells with head loss
[in]	ncesmp	number of cells with mass source term
[in]	icepdc	head loss cell numbering
[in]	icetsm	numbering of cells with mass source term
[in]	itypsm	kind of mass source for each variable
[in]	dt	time step (per cell)
[in]	ckupdc	work array for head loss terms
[in]	smacel	values of variables related to mass source term. If ivar=ipr, smacel=mass flux
[in]	mijlij	mij.lij before the local averaging
[in]	mijmij	mij.mij before the local averaging

usvist()

subroutine usvist	(	integer	nvar,
		integer	nscal,
		integer	ncepdp,
		integer	ncesmp,
		integer, dimension(ncepdp)	icepdc,
		integer, dimension(ncesmp)	icetsm,
		integer, dimension(ncesmp,nvar)	itypsm,
		double precision, dimension(ncelet)	dt,
		double precision, dimension(6,ncepdp)	ckupdc,
		double precision, dimension(ncesmp,nvar)	smacel
	)

Modify turbulent viscosity.

This subroutine is called at beginning of each time step after the computation of the turbulent viscosity (physical quantities have already been computed in usphyv).

Turbulent viscosity (kg/(m s)) can be modified.

A modification of the turbulent viscosity can lead to very significant differences between solutions and even give wrong results.

This subroutine is therefore reserved to expert users.

Parameters

[in]	nvar	total number of variables
[in]	nscal	total number of scalars
[in]	ncepdp	number of cells with head loss
[in]	ncesmp	number of cells with mass source term
[in]	icepdc	head loss cell numbering
[in]	icetsm	numbering of cells with mass source term
[in]	itypsm	kind of mass source for each variable
[in]	dt	time step (per cell)
[in]	ckupdc	work array for head loss terms
[in]	smacel	values of variables related to mass source term. If ivar=ipr, smacel=mass flux