INTFRC

---- PIL integer name; group 7 ----------

INTFRC.... indicates which whole-field store will be used for the interphase friction coefficient in response to the command STORE(CFIPS). Such storage is necessary when it is desired to under-relax this coefficient. Once stored, this field should be initialized in group 11.

INTMDT

---- PIL integer name; group 7 ----------

INTMDT.... indicates which whole-field store will be used for the interphase mass-transfer rate in response to the command STORE(CMDOT). Such storage is necessary when it is desired to under-relax this flux. Once stored, this field should be initialized in group 11.

INTRPT

------------ Advanced PIL command --- -

The syntax is: INTRPT(R,filename) INTRPT(W,filename)

INTRPT(R,filename) will interpret and execute lines in the named file as PIL.

INTRPT(W,filename) will dump the current contents of COPYQ1 to the named file.

INTSOR

------------- Command; group 10 ----------- INTSOR

INTSOR... activates the calculation of various non-drag sources in the IPSA phasic momentum equations. The syntax is as follows:

1. INTSOR(VMASS) activates calculation of momentum sources to account for virtual ( or added ) mass forces in dispersed two-phase flows. The command is equivalent to:

   USOURC=T;PATCH(VMASS,CELL,1,NX,1,NY,1,NZ,1,LSTEP) COVAL(VMASS,U1,TINY,GRND4);COVAL(VMASS,U2,TINY,GRND4) COVAL(VMASS,V1,TINY,GRND4);COVAL(VMASS,V2,TINY,GRND4) COVAL(VMASS,W1,TINY,GRND4);COVAL(VMASS,W2,TINY,GRND4)

   The magnitude of these forces is controlled by the empirical coefficients CVM (=RSG35) and CVMA (=RSG34), which are described under the Encyclopaedia entry 'VIRTUAL-MASS MOMENTUM SOURCES'. Default values of CVM=0.5 and CVMA=0.5 are set by INTSOR, but these may be changed by using INTSOR(VMASS,CVM,CVMA).

2. INTSOR(LIFT) activates calculation of momentum sources to account for interfacial lift forces in dispersed two-phase flows. The command is equivalent to:

   PATCH(LIFT,CELL,1,NX,1,NY,1,NZ,1,LSTEP) COVAL(LIFT,U1,TINY,GRND4);COVAL(LIFT,U2,TINY,GRND4) COVAL(LIFT,V1,TINY,GRND4);COVAL(LIFT,V2,TINY,GRND4) COVAL(LIFT,W1,TINY,GRND4);COVAL(LIFT,W2,TINY,GRND4)

   The magnitude of the lift forces is controlled by the empirical coefficients CLIFT (=RSG31) and CLIFTA (=RSG30), which are described under the Encyclopaedia entry 'INTERFACIAL-LIFT MOMENTUM SOURCE TERMS'. Default values of CLIFT=0.1 and CLIFTA=0.1 are set by INTSOR, but these may be changed by using INTSOR(LIFT,CLIFT,CLIFTA).

3. INTSOR(INTPS) or INTSOR(INTPL) activates calculation of momentum sources to account for interfacial-pressure effects in dispersed-fluid two-phase flows. The command is equivalent to:

   PATCH(INTP*,CELL,1,NX,1,NY,1,NZ,1,LSTEP) COVAL(INTP*,U1,TINY,GRND4);COVAL(INTP*,U2,TINY,GRND4) COVAL(INTP*,V1,TINY,GRND4);COVAL(INTP*,V2,TINY,GRND4) COVAL(INTP*,W1,TINY,GRND4);COVAL(INTP*,W2,TINY,GRND4)

   where *=L for the formulation of Lahey et al [1993], and *=S for the formulation of Stuhmiller [1977].

   The magnitude of the interfacial-pressure forces is controlled by the empirical coefficients CPIP (=RSG33) and CPIPA (=RSG32), which are described under the Encyclopaedia entry 'INTERFACIAL- PRESSURE MOMENTUM SOURCES'. Default values of CPIP=0.25 and CPIPA=0.25 are set by INTSOR, but these may be changed by using INTSOR(INTP*,CPIP,CPIPA).

4. The INTSOR command may also be utilised to introduce storage, printout and linear under-relaxation of the interfacial forces. This facility requires extension of the INTSOR argument list to include RELAX and RLXFAC as the last two arguments, e.g:

   INTSOR(LIFT,CLIFT,CLIFTA,RELAX,RLXFAC)

The argument RELAX activates the facility with a default linear- relaxation factor of 0.1. The argument RLXFAC is optional, and it serves to change the relaxation factor from its default value

INTTYP

-------------------------------------

Ground integer.

INTTYP....is the integer number corresponding to the current patch type. See TYPE.

wbs