Using Computational Aerodynamics to create flight models

One of the challenges presented to any one making an aero model is finding the data; so for a long time I've been researching into alternative methods of building an aero model - when there is no wind tunnel data, or to augment an existing wind tunnel model. For example with the F-14 I had good data, except for spoilers, flaps and stores -because these weren't relevant within the scope of the original paper; so I guesstimated them and as I was doing this I kept thinking that there has to be a better way.

Rather naïvely I thought this would be fairly easy, take a 3d model, use that as a basis for a mesh and a few hours of CPU and out pops a model. I was, of course, very, very, wrong and I now realise that most of the 3d models are subtly wrong, that a polygon based model isn't up to the job, and even if it was most models just aren't accurate enough where it is important for computations.

My interest in this topic is long standing, something that's been on the back burner for the better part of a decade, however recent advancements in freely available software meant that during 2015 I started to seriously investigate how to build a represenative model using one of the (non CFD[1]) computational methods.

After a fair amount of investigation into the available methods I've settled upon using OpenVSP - which has both a geometrical vehicle modeller, a vortex lattice method solver and (since 3.9.1) a flat panel solver. My results are from the VLM solver.

OpenVSP is really powerful, and there is a lot to understand about how to drive it. The geometrical approach is well suited, and fits well with VSPAero. I started off modelling by trying to get something that was close to the real thing, but now I'm modelling to what works well with VSPAero (i.e. the degenerate geometry).

The approach taken to validate OpenVSP was to build an F-15 aero model and compare that against the wind tunnel data, and to see how close I can get it. This worked reasonable well, although some data is a little different, but probably ok.

After the F-15 I've built a BAe Hawk T2 model which flys quite nicely, but isn't finished.

More recently there is the Beagle Pup project. This is an evaluation of differing techniques for creation of an aero model where little data is available. 

[1] I initially discounted CFD on the basis that it would probably work quite well, but require CPU years to get something usable.
[2] Usual disclaimer applies; in that I've never flown one in real life so it might turn out to be quite unrealistic.