I'm currently trying to solve a (very simple?) 2 phase problem in CFX. I have a box with the air in the top half and water in the bottom half and there is a flow through the box. I'm trying to set the pressure on the outlet to be hydrostatic in the water part. This is proving to be far more difficult than it should be.

In subroutine USRBCS I use CALL GETVAR('USRBCS','P ',IVAR)

and then after calling subroutine IPREC for the outlet.

VARBCS(IVAR,1,INODE) = RHOW*GRAVITY*(0.52 - ZP(INODE))

where 0.52 - ZP(INODE) is the height term.

I've written data to a file within this routine, I know that the IPREC gets the outlet, I calculate the correct value for pressure, but when I look at the values of P(INODE,1) across the outlet they are all zero. It's confusing me no end, can anyone help?

Have you set IUBCSF correctly?

Gert-Jan

Richard It is not necessary to use GETVAR because the utility gives you the variable value throughout the computation domain. You can just use the IPREC to get the variable pointer(IPT) on boundaries. These pointer help you get variable location you desired.

ex. P(ipt(i),iphase) = roh * zc(ipt(i))

try it.

Darcy.