TALK=F;RUN( 1, 1)

  load the original library case of the ship stern flow

#B530

lsweep=500

INTEGER(ICAS)
MESG(
MESG(            3D BFC SHIP STERN with MIGAL
MESG(
MESG(
MESG( This file illustrates two different ways for damping
MESG( the non-linear oscillations that may occur during the
MESG( solution procedure on coarse grids : 
MESG(
MESG(   1) using the LINRLX parameter of MIGAL
MESG(   2) using the FALSDT parameter of PHOENICS
MESG(
MESG(
MESG( Enter the case :  1 - use LINRLX (default) 
MESG(                   2 - use FALSDT
MESG(                   3 - no damping
MESG(
READVDU(ICAS,INT,1)

  Use MIGAL for the velocity and pressure coupling (HYDRO)

spedat(MIGAL,SOLVED1, c, HYDRO)

CASE ICAS
WHEN 1

   Use large false time step and under-relax the corrections
   before updating the velocity and pressure fields

 + spedat(MIGAL,LINRLX1, r, 0.5)
 + relax(u1,falsdt,1.E+10) 
 + relax(v1,falsdt,1.E+10) 
 + relax(w1,falsdt,1.E+10) 
 + lsweep=15

WHEN 2

   Use the false time steps to under-relax the velocity field. This
   increases the diagonal dominance of the operator and then that we can
   set the relaxation factor of the multigrid smoother to 1. The number 
   of iterations on each grid level is also reduce to 1 to save CPU time. 

 + spedat(MIGAL,LINRLX1,  r, 1.)
 + spedat(MIGAL,RELAX1,   r, 1.)
 + spedat(MIGAL,NBRELAX1, i, 1 )
 + relax(u1,falsdt,5.E-2) 
 + relax(v1,falsdt,5.E-2) 
 + relax(w1,falsdt,5.E-2) 

WHEN 3

   Don't use any under-relaxation (large FALSDT and LINRLX=1) 

 + spedat(MIGAL,LINRLX1,  r, 1.)
 + relax(u1,falsdt,1.E+10) 
 + relax(v1,falsdt,1.E+10) 
 + relax(w1,falsdt,1.E+10) 

ENDCASE