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-   -   Head (m) as in put parametrer (https://www.cfd-online.com/Forums/cfx/128038-head-m-put-parametrer.html)

obliqueshrestha January 1, 2014 00:14

Head (m) as in put parametrer
 
How to input head (m) as a input parameter??? I have tried using this constant mass flow rate in different guide vane angles but the result of head head varies from 750 m to 12 m which in my veiw no possible.


My script is


LIBRARY:
CEL:
EXPRESSIONS:
Accumulated Time Step = 100
Angular Velocity = 529 [rev min^-1]
Current Time Step = 100
H net = Hin -Hout
Head = Total Pressure in Stn Frame/gama
Hin = massFlowAve(Head )@Inlet
Hout = massFlowAve(Head )@Outlet
Hydraulic power = gama *Q *H net
Q = massFlow()@Inlet /massFlowAve(Density)@Inlet
Reference Pressure = 1 [atm]
Sequence Step = 100
Time = 0 [s]
atstep = Accumulated Time Step
ctstep = Current Time Step
efficiency = (shaft power /Hydraulic power )*100
gama = 9806 [N*m^-3]
omega = Angular Velocity
shaft power = (torque_x()@Rotating Default )*(omega*2*pi/(360[degree]))
sstep = Sequence Step
t = Time
END
END
END

Please help me with this matter

ghorrocks January 1, 2014 04:22

WHy not just define the inlet as a total pressure boundary and the outlet as a pressure boundary? Then you simply define the pressure loss over the system. Read the documentation section on "Choice of boundary conditions" for further details.


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