Guidance sought - drag of a sphere with bump
 

Dear CFD experts,

I'm working on a Computer Science research project in the field of machine learning. I'm so close to the end, I can almost taste it, but I've been asked to do some extra experiments using an artificial data set with some particular properties.

I will generate 1000 high-resolution sphere & cube-meshes (STL or OBJ format), with some subtle differences (small surface ridges at random positions). I then need the drag values for each of these 1000 spheres to complete my data set.

I've been directed to use OpenFOAM, with which I have very little experience. I've spent the past few hours looking through the example folders and running some of them in order to see if I can easily acquire the drag value from the converged files, but as of yet, no luck.

My questions from anybody kind enough to give me some advice:

1. I understand I am to use a particular solver. Can I get drag data using the simpleFoam solver? If so, how do I get a singular drag value from the data?
2. The motorBike example in the simpleFoam appears to load an OBJ file, generate a CFD mesh, run the simulation and output the data files. What modifications to this example would be needed before I had it load one of my sphere/cube STL/OBJ's?
3. What advice can you give?

Please forgive the naivety of some of these questions. Physics and aerospace are not fields I am knowledgeable in.


I don't necessarily need the "most appropriate" method, obviously this is a toy problem and I'm mostly interested in the machine learning side of things. That said, the data set needs to exhibit the same properties that aerodynamic functions of shape (such as drag) exhibit because the motivation behind the research is closely related to this.


Thanks in advance for taking the time to read and respond,

Matt