Thermal analysis and modelling of cryogenic coolant flow in an aerospike engine additively manufactured cooling channel

Abstract

Cryogenic propellants play a crucial role in regenerative cooling systems of liquid rocket engines, particularly in high-heat flux applications such as aerospike engines. The present study is conducted within the framework of the DemoP1 demonstrator, a 20 [kN] LOx/LNG Additively Manufactured (AM) aerospike engine developed by Pangea Aerospace. This work aims to present a numerical characterisation of the cryogenic liquid oxygen flow within an AM cooling channel of the DemoP1 demonstrator. To analyse the development of the fluid primitive variables, the objective of this study is to provide a detailed assessment of the thermophysical properties and dimensionless numbers governing the cryogenic flow. The numerical findings are compared against experimental data obtained from the full-scale, single-injector hot-fire testing campaign of the demonstrator. The results highlight the enhanced heat transfer performance of AM cooling channels with high process-inherited roughness compared to conventional smooth-surface channels. Finally, a modified Dittus–Boelter correlation is introduced to characterise the heat transfer behaviour of the cryogenic flow in the AM channel. The case study presented here consists one of the first attempts to provide a comprehensive analysis on the cryogenic flow characteristics in the novel dual regenerative cooling system of an aerospike engine.