High order panel modeling units?

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The discussion centers on the use of the Pan Air (A502) high-order panel method for modeling 3D airflow, specifically regarding the units and scaling of coefficients such as Cl, Cd, and Cm. The user notes that while the free stream velocity is normalized, this affects the geometry and the resulting coefficients, which are expected to be non-dimensional. There is confusion about how to incorporate air density and dynamic pressure into the model, as the software does not provide clear guidance on rescaling these factors. The need for clarity on input parameters like span and area is emphasized, as they significantly influence the reported results. Overall, the lack of detailed instructions in the manual complicates the accurate modeling of airflow around arbitrary bodies.
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I have a copy of Pan Air (A502) which is a high-order panel method used for modeling 3D airflow around arbitrary bodies. I've read the manual, but I'm not clear about the units used. As I understand it, the free stream velocity is normalized which implies that all the other geometry is scaled by the same factor used to normalize the free stream velocity to a unit vector. No problem with that. But this is going to affect all the various factors it solves for, namely Cl, Cd, Cm, Cdi, and so on. There's also no place to enter the air density. So my question is how do I rescale the various coefficients to restore the units and take density into account?
 
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I am not familiar with that software, but the whole point of the force and moment coefficients is that they are supposed to be nondimensional and allow easy scaling of their respective quantities for a given set of dimensional conditions. Why do you feel you need to rescale them somehow?
 
I understand that the coefficients are technically non-dimensional. But the program asks for things like span and area which is causing the reported numbers to change dramatically. It's pretty clear it's deriving the coefficients by dividing the forces by the area & span as needed, but the dimensions you need to give it is not clear. Plus, none of the input parameters reflect the dynamic pressure.

It seems the model needs to be scaled by both the free stream velocity and by Q. However, no method is described in manual for doing this.
 
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