Learning Forum

[Gregory Harrington]

I am modeling internal flow through 1/20th of the circumference of a flow volume. There are periodic walls on either side of the inlet.

The flow at the inlet is ideal gas with Mach ~0.6-0.7. The inlet is modeled as a mass flow inlet with constant mass flow and prescribed axial, radial, and tangential components. The outlet is modeled as a static pressure outlet. The actual flow domain is rotationally symmetric so the computational domain is a slice that is 1/20th of the actual domain so there are periodic BCs on eithheer side ofo the inlet. 

I am using pressure based coupled solver (PBCS) with default settings and K-omega SST turbulence model.

The ambient condition is 1.68 psia so I changed that in the operating conditions and set the operating density to 0 since the air is an ideal gas

As you can see I am getting a massive static pressure difference across the inlet face where the BC is a mass flow inlet. This is also leading to unrealistic velocity and density distributions across that face as well. The average static pressure is only 50 psi. The max static pressure on that face is almost 100 and the minimum static pressure on the face is only 30 psi which is lower than that of the domain's static pressure outlet. 

The inlet face is only 80 mm in diameter so this large difference across the face can't be just from hydrostatic effects.

Are there any additional settings I need to change to fix this?

 

[Rob]

Odd. Please can you post images of the panels setting the inlet conditions, along with those for the cell zone and inner radius wall?