Hello, everyone. I want to model pressure driven flow with MFIX-DEM. Pressure driven flow means that fluid flows under constant differential pressure between inlet and outlet.
Attached is a test model that I try to realize pressure driven flow. The boundary condition on inlet is “mass inflow” with constant pressure of 2 atmospheres. The boundary condition on outlet is “pressure outflow” with constant pressure of 1 atmospheres. However, the model results show that the pressure in the entire CFD domain is 1 atmospheres. I want to understand why and appreciate some help. Thanks very much! test.mfx (18.3 KB)
Hi Yajing
test.mfx (23.5 KB)
I added 6 point monitors M0-M5 evenly spaced through the domian from zmin to zmax. I also changed reference pressure
p_ref to 0 to make it easier to compare pressure values. The pressure at M0 matches the specified inlet pressure and M5 matches the outlet. The other values are all above the outlet pressure, but are a lot closer to the outlet than the inlet pressure - it seems that the pressure drops off very quickly as we get away from the inlet, but it is not constant.
– Charles
Thanks very much! I will obtain the model results as you suggest.