Optimizing a small rocket nozzle to maximise the Mach number involves carefully designing the nozzle’s geometry—primarily its converging-diverging shape—to ensure efficient acceleration of exhaust gases from subsonic to supersonic speeds. The key objective is to achieve optimal expansion of combustion gases through the nozzle throat and into the divergent section, where the Mach number can increase significantly. This requires balancing factors such as chamber pressure, temperature, and nozzle expansion ratio to minimise losses due to shock waves, flow separation, or over/under-expansion. For small-scale rockets, additional considerations like manufacturing tolerances, heat transfer, and boundary layer effects become critical, often requiring computational fluid dynamics (CFD) simulations from SolidWorks and iterative testing to fine-tune the nozzle profile for peak performance in a given flight regime.

​

As a result, we were able to design a rocket nozzle in which the exiting gases reached a mach number of 3 (3-times the speed of sound) which would be considered as "hyper-sonic" as sea level. Of course, our simulations are ideal, thus practical testing would reveal the actual performance of our design. However, the BURPG club was unable to provide a rocket engine to test. Thus, a high-temperature prototype was not 3D printed.