Hi
For the package, if you only have external fluid dynamics problems. You only need the basic package, that includes flow, turbulence, heat transfer and all post processing tools. The setup is very straightforward. Most of external fluid problems, we can get the converged solution in couple minutes. We can also show the results in the real time during the calculation.
For the cl, cd and center of pressure calculation, you can select the surface and create a xyplot to monitor pressure or shear force on that surface.
To compute lift and drag coefficient, we can use expression to do that very easily. You can use expression to define equations and formula. We also support user defined variable for xyplot.
Example of cl, cd calculation
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den=1.16
area=1
aoa=15*pi/180
vmag=200
cx=cos(aoa)
cy=sin(aoa)
nx=-cy
ny=cx
drag=(flow.px@patch.surfname + flow.tx@patch.surfname)*cx
+(flow.py@patch.surfname+flow.ty@patch.surfname)*cy
lift=(flow.px@patch.surfname + flow.tx@patch.surfname)*nx
+(flow.py@patch.surfname+flow.ty@patch.surfname)*ny
plot.cd = drag/(0.5*den*vmag^2*area)
#plot.cd: Drag Coefficient []
plot.cl = lift/(0.5*den*vmag^2*area)
#plot.cl: Lift Coefficient []
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here flow.px@surfname means pressure force x component from flow module at surfname patch
similarly, flow.tx means shear force x component.
For the center of pressure, we need to do an integration of x times pressure of x component on all external surfaces and it is straightforward to use expression to write it.
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cpx = integral(x*flow.pressure*normal.x, patch.surfname)/flow.px@surfname
plot.cpx = cpx
#plot.cpx: Center of Pressure x []
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Please contact me if you got further questions!
Thanks.
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