Mass Flow Rate Over a Sampled Surface
Hey guys,
I'm looking to calculate the mass flow rate over a sampled surface. The current function I'm using in controlDict looks like this... Code:
faceObj1 When changing the function to use a weighted average based on a sample surface and phi, I can get it to produce the following error. Code:
--> FOAM FATAL ERROR: |
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That being said: something like this could be done in swak4Foam. But for the reason given above (no interpolation, orientation) using phi won't work. Instead you'd have to "emulate" it with an expression like "rho*U & Sf()" (Sf() is the surface vector of a phase) and sum it |
Bernhard, thank you for your response. This is what I have so far...
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flowBeforeSet Do you know what could be causing this difference? Does the inclusion of Sf() in the swakExpression mean that only the values normal to the surface are being taken into account? Also, is it possible to interpolate the values being used for the mass flow calculation to perhaps get a more accurate results? When I turn interpolate on it throws an error at me. Thanks! |
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Expression Ratio_not_Normal : min=0.8991376591 max=0.96846234 average=0.9064741362 Also, for reference, this is the error I receive when I turn interpolation on for the Sampled_Mass_Flow... Code:
--> FOAM FATAL ERROR: |
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With control surfaces that are not aligned to the cell faces you always have got to expect an error. How big it is depends on the circumstances but if the 90% are correct they are not favourable Quote:
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Use normal() instead of Sf()
To get the correct massflow (m3/s) you need to use the expression.
Where normal() is the normal vector of the plane expression "(area()*(normal()&U))"; It should work :) |
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