CFD simulation of rockets

Hello everyone,

Who here runs CFD (computational fluid dynamics) simulations on their rocket designs? Is there any point of doing it? Because I'm thinking of picking up AutoDesk Simulator CFD and I don't know if there's any point In doing so. Also, are there any good free CFD programs that you guys would recommend?

Thanks, David

I'm toying with the idea but have yet to try it.

I am doing a series of tube fin simulations for the OpenRocket project. Getting good volume grids is non-trivial even for simple geometries. I am using OpenFoam which is an open source cfd solver, Rhino for the geometry and Pointwise for the grid generation.

Setting up grids for a parametric series of tube fins is taking considerably more time than I originally planed, I had hoped to automate the grid generation but that has not proven feasible at this time.

The question I would have is - unless you want to do it for the simple academic joy, why? It would be, to me like doing FEA on a launchpad we would use. Massive overkill.

Still, if it would be fun, do it. That is why we are in the hobby.

I think AeroCFD is no longer openly available, however there is a note on the website that if you make a use-case to the author he will give you a copy.

I agree with the above points...for the 3FN or 4FN rocket, the trouble you have to go through to get the mesh and results aren't worth it unless you are trying to model something like supersonic heating or such.

I have modeled the Estes Alpha in two different packages: FloWorks (couples with SolidWorks) and ANSYS Fluent. It was challenging to get everything to mesh, especially around the fins and launch lug. I have a copy of AeroCFD, and you are pretty limited to just the body of revolution and fin (no protruberances like lugs, etc).

Below are pressure plots from all three packages. The general pressure distribution around the nose seems to agree between the three.

I too was going to try modeling tube fins and have run into the same problems trying to mesh the model. We have a limited number of CFD licenses at work, and they are in nearly constant use by our full time CFD guys, so I can't justify tying up the program for "government work". One of the analysts recommended Openfoam, but I have not been successful in getting it installed on my former XP machine that I converted to Ubuntu. The install fails and I am not enough of an Ubuntu geek to know how to fix it. I will be very curious to follow your work djkingsley, please keep us posted!

Nice info; thanks for sharing David.

I just found this today...I did not know Openfoam was available for Windows...I struggled and gave up trying to install the Ubuntu version, but this looks interesting. There is also a Linux "Openfoam in a Box" which states it has run on Ubuntu. They say they are free, but I am curious if anybody else tried this.

I'm installing a substantial piece of automation at a customer's site where they do extensive cfd and have two wind tunnels. The vp of engineering offered to run my rocket through the software and the wind tunnels... Haven't had a chance to take him up in it.