[ikrash]

Hi all,

I am transient simulating a 2-D axisymmetric CD nozzle with an inlet and discharge box on either side of the nozzle (to be able to see the fluid jet propagating through the nozzle and exiting).

Currently, I am initializing the simulation from outlet pressure conditions of 10 Pa and then patching the inlet box with 50 kPa.

Simulations run relatively well and convergence is observed, however, I was wondering if anybody here has written a UDF to ramp the patch pressure from outlet conditions up to 50 kPa to reduce the gradient and minimize rarified gas dynamic effects.

Thank you.