Aerodynamics
Overview
The Aerodynamics Department is mainly tasked with modeling the aerodynamic forces and analyzing the fluxes generated by our flight systems. We accomplish our goal mainly through the use of CFD (Computational Fluid Dynamics) softwares that allow us to predict the aerodynamic force coefficients, which are then validated by performing wind tunnel tests and compared to “real” flight data. Our department is also involved in determining the best configurations for the air brakes, fins, pressure taps and the Pitot tube, while also aiding the Recovery System in the design of the rocket’s parachutes and parafoils. Most of our CFD simulations are run on OpenFOAM, Altair HyperMesh and Ansys Fluent, while we use Matlab to code in Python our post-processing data software.
Computational Mesh Design
The computational grid generation is one of the key parts of any CFD simulation, as a well designed mesh needs to include refinement in the right places, boundary layer cells capable of capturing both viscous and separation forces, and it must be suitable to model all physical phenomena.
CFD Simulations and Post-Processing
Once the mesh is generated, CFD simulations are run under different boundary conditions, which take into account multiple flight parameters such as velocity, pressure, or altitude. Furthermore, we consider different flight conditions, like steady-state or transient, compressible or incompressible, and supersonic or subsonic simulations. After all this data-gathering we check the convergence plots and proceed with a post-processing of the results to extrapolate force coefficients, pressure values and flow visualizations.
Wind-Tunnel Tests
To validate all CFD simulation data, which can be limited due to limited computational resources (i.e. wake frequency), we run extensive wind tunnel simulations while also calibrating self-made sensors like pitot probes.
Pressure Measures Consulting
As the aerodynamic data we gather affects the work of all departments working on integral parts of the rocket, we provide consulting regarding some specifications they need to follow. For example, we provide the Structures Department characteristics such as size, position and diameter, for the pressure taps and probes they then design and produce.