Helios Engine Design
The mixture ratio, chamber stagnation pressure, the exit pressure, and the flow rate are chosen subjectively. Then, the specific heat ratio, gas constant, and the chamber stagnation temperature are taken from tables online given the mixture ratio and chamber stagnation pressure.
The exhaust velocity, thrust, Isp, expansion ratio, throat radius, exit radius, characteristic velocity, and thrust coefficient are calculated from experimentally-derived equations in Huzel & Huang