Analysis and Optimization of Scramjet Inlet using Computational Fluid Dynamics

Scramjets are air breathing engines with no moving parts. They rely on the 'ram-air' effect. This is done with the help of oblique shockwaves. The inlet geometry is used to slow down hypersonic air to supersonic speeds to achieve compression, which is then used to burn fuel and accelerated through a diverging section to achieve thrust. The main challenge in making scramjets viable is the lower Mach threshold of its operating range, which is quite high i.e. Mach 3-4. This paper aims at using optimization techniques in CFD (CFX) to reduce the lower threshold of the operating range of the scramjet to between Mach 2.5 to 3. This is mainly achieved by manipulating the inlet geometry. This is done by simulation of flight in a Mach range with available experimental data, validation of the simulation methodology, and application to a lower Mach domain. Optimization techniques were used to generate geometric parameters which provided positive results in lower Mach ranges.