DATE     96/10/08


    Opérateur BIF                                      voir aussiPPRE 
    _____________                                                FROT 


    SYNTAXE (EQEX) : Cf opérateur EQEX
    _______________


    'OPER' BIF  tabbif








  Description: The BIF operator computes the qdm and energy
               interactions coefficients between a gas and a
               'particles fluid'

  qdm:         Bif computes Kp and Kg. The terms Ip and Ig are
               assembled via FROT.

               Ig   : gas      qdm source term
               Ip   : particle qdm source term
               [Ig] = [Ip] = m/s^2 (force/unit mass)
               Ig   = Kg * (Upart - Ugas)
               Ip   = Kp * (Ugas  - Upart)
               Kg   = Fd * alpha
               Kp   = Fd * rhog / rhop
               Fd   = (9/2) * nug * (1 + 0.241 * Re^0.687) /Dp^2

  energy:      Bif computes Hp and Hg. The terms Qp and Qg are
               assembled via ECHI.

               Qg   : gas      energy source term
               Qp   : particle energy source term
               [Qg] = [Qp] = K/s
               Qg   = Hg * Volume * (Tpart - Tgas)
               Qp   = Hp * Volume * (Tgas  - Tpart)
               Hg   = H  * 6 * alpha / Dp / rhoCpg / Volume
               Hp   = H  * 6 / Dp / rhoCpp / Volume
               H    = Nu * lambdag / Dp


  tabbif           TABLE
  tabbif.'RHOF'    FLOTTANT Fluid density
  tabbif.'RHOP'    FLOTTANT Particle density
  tabbif.'DPART'   FLOTTANT Particle diameter
  tabbif.'NUF'     FLOTTANT Fluid kinematic viscosity
  tabbif.'ALPHA'   MOT     CHPOINT (SCAL SOMMET) in table INCO for alpha
  tabbif.'UFLUID'  MOT     CHPOINT (VECT SOMMET) in table INCO for Uflui
  tabbif.'UPART'   MOT     CHPOINT (VECT SOMMET) in table INCO for Upart
  tabbif.'KFLUID'  MOT     CHPOINT (VECT CENTRE) in table INCO for Kf
  tabbif.'KPART'   MOT     CHPOINT (VECT CENTRE) in table INCO for Kp

  The following only in case of thermal analysis

  tabbif.'HPART'   MOT     CHPOINT (SCAL CENTRE) in table INCO for Hp
  tabbif.'HFLUID'  MOT     CHPOINT (SCAL CENTRE) in table INCO for Hf
  tabbif.'LAMBDAF' FLOTTANT Fluid thermal conductivity
  tabbif.'ROCPF'   FLOTTANT Fluid thermal capacity (rho * Cp)
  tabbif.'ROCPP'   FLOTTANT Particle thermal capacity (rho * Cp)
  tabbif.'TGASN'   MOT     CHPOINT (SCAL SOMMET) in table INCO for Tgas
  tabbif.'TGASE'   MOT     CHPOINT (SCAL CENTRE) in table INCO for Tgas
  tabbif.'TPARTN'  MOT     CHPOINT (SCAL SOMMET) in table INCO for Tpart
  tabbif.'TPARTE'  MOT     CHPOINT (SCAL CENTRE) in table INCO for Tpart

  note: Bif checks the existence of tabbif.'HPART'