Solution of reactive flow in a rocket engine nozzle with Paraffin/Kerosene propellants

Abstract

AbstractThis paper presents a simulation‐based solution for calculating rocket engine performance with liquid‐type propellants of Paraffin and Kerosene for oxidizer to fuel ratio that is given by a linear formula. The engine was divided into two main stages: combustion chamber and a nozzle. In the first phase, conditions were found in the combustion chamber, based on the assumption of equilibrium according to Barrere. Next, the flow in the nozzle was calculated based on the fluid in the combustion chamber. Three main theories were examined in order to find the flow conditions in the nozzle: equilibrium, frozen and mixed flows (Bray conditions). While the latter assumes the existence of the “Sudden Freezing Point” found by Bray, so that from this point to the end of the nozzle, the flow is assumed to be frozen. The use of the proposed simulation might contribute for multiple calculations performance (e.g., fuels with multiple intermediate reactions). Comparison between both types of fuels/propellants for the three described types of flow is presented alongside CEA software results, whereas good agreement between solutions was found. Also, the greater the ratio between hydrogen and carbon atoms, the better the engine performance for a particular oxidizer. Finally, it was found that an equilibrium flow model throughout the nozzle has a better nozzle performance compared to the other types of flows.