Master thesis and internship[BR]- Master's thesis : CFD study of a rocket[BR]- Integration internship : Thalès Belgium SA

Abstract

This thesis aims at obtaining the aerodynamic coefficients, in particular the drag coefficient, of a rocket developed by Thales SA Belgium. The simulation have been done using only open-sources software.

The wake of the rocket is turbulent due to high Reynolds number. Two turbulence models have been investigated in order to close the Reynolds-Averaged Navier-Stokes (RANS) equation during the simulations, the Spalart-Allmaras one-equation model and the k-omega SST two-equation model introduced by Menter.

Both subsonic and supersonic regimes have been discussed with a focus on Mach 0.5 and 1.5. The flow field is characterized by a separation in the wake in both regimes and shock waves in supersonic flow causing respectively the base and wave drag. The wave drag is the predominant source of drag for supersonic flow, followed by the base drag, and finally the friction drag. In subsonic flow, the wave drag is not present due to the absence of shock. This time, the friction drag is the main source of drag of the rocket.

The drag coefficients of the flying rocket could have been extracted from radar data. They have been then compared with those obtained through the RANS simulations. This comparison shows good agreements between the simulated and experimental drag coefficients for different Mach numbers.