Preliminary design of a vortex cooled hydrogen peroxide/kerosene rocket engine

This workdetails the design of a 3000Nliquid bipropellant rocket engine for apogee application using hydrogen peroxide and kerosene, intended to provide an alternative to existing engines in its class, which often make use of highly toxic and pollutant hypergolic propellants. The idea of shifting away towards greener and safer propellant engines has become prevalent in recent years, both for the environmental benefits and the less serious safety concerns associated with them. Significant research has in fact been conducted on the matter, showing promise in delivering performance comparable with SoA examples. The engine in question differs from most other designs in due to its novel combustion chamber cooling method, known as Vortex-Cooled Chamber Wall (VCCW), which is based on the flow field inside of the chamber itself, characterized by two counter-flowing coaxial vortices, the outer one responsible for the cooling of the chamber wall, and the inner one containing the combustion reaction. The first chapters of this thesis focus on introducing the problem, laying out the theoretical background needed. Areview of the state of the art of apogee engines is then carried out with the aim of assessing the design requirements for the engine, followed by a chapter detailing the choice of the fuel, made on the basis of literature review and performance estimation. Having defined the requirements and the fuel, a preliminary design of the chamber is carried out. The flow field is modeled and a simplified thermal analysis of the system is conducted in order to determine the performance of vortex cooling and of combined cooling solutions for the chamber; the nozzle on the other hand is regeneratively cooled with liquid hydrogen peroxide. After having laid out the models, an analysis of the influence of a certain set of input variables on some relevant outputs is carried out. Lastly, the final design configuration is presented, among with some alternatives that implement different thermal control solutions.