Total pressure distribution at boundary as a named expression
 

Hi,

I am modeling a fan in FLUENT 2021R2 by prescribing a pressure outlet boundary condition at the fan intake, and a pressure inlet boundary condition at the fan outlet. I know the fan pressure ratio FPR equals 1.4 (= ratio of total pressure at the fan outlet and the fan intake).

For the pressure inlet boundary condition at the fan outlet, a total pressure input is required. Ideally I would like to prescribe an expression containing the total pressure distribution at the fan intake, and "scale" that distribution using the FPR. I know FLUENT is capable to deal with non-single-valued expressions because I can manage the above mentioned using a read-in "profile", but that "profile" stays constant in simulation and this is undesired.

Now I have tried to specify a named expression "TotalPressure(['fan_intake'])", but this syntax does not yield me the total pressure at the fan intake, when specified as a total pressure distribution at the fan outlet. Reduction formulas like "AreaAve(TotalPressure,['engine_intake'])" do work, but only this yields a scalar value forcing a constant total pressure.

Is there a syntax that allows me to define the total pressure distribution at a specific boundary as a named expression such that I can access it in another boundary condition dialog box? Or is this not supported in FLUENT without the use of UDF? All suggestions to solve this are welcome!

Hope to hear from you! Thanks in advance.