I was an Aerospace Engineering intern at RapidFlight LLC, which is an additive manufacturing UAS startup. I worked under Salim Roustom, the primary computational fluid dynamicist for the company. At RapidFlight I focused on fluid dynamics and simulations in addition to fluid component design. You can see an example of one of RapidFight's UAVs above. All of the gray material that you can see above is 3D printed structural elements (excluding the camera). 

One of my first responsibilities was aiding in completing CFD  simulations. I helped set up and run CFD cases for our aircraft and other devices, primarily using ANSYS Fluent. I can't share details about the topics or results of these simulations (NDA), but I can say that I helped with meshing and setup, as well as post-processing. I gained experience with Fluent and Paraview, and learned a massive  amount from Salim.

In addition to documenting and modifying internal fluid dynamics and propulsion codes, I also created my own simulations. One simulation that I created that I can talk about is a dive-pull up simulation of the NOAA HORUS aircraft. NOAA HORUS is a data collection aircraft that is dropped by a balloon at ~95,000 feet. The aircraft is initially vertical, before it pulls up into a slight negative AOA as it descends. I wrote a simulation of this aircraft performing the dive-pull up maneuver in Python to help optimize the aircraft design, and test our suggestions for NOAA. The simulation was able to systematically test different wing geometries, airfoils, and other aspects of the aircraft to find what design produced the lowest altitude loss. Below you can see what the NOAA HORUS aircraft looks like (note its very stubby wings).