Thermal Performance Analysis of LOX/LCH4 Engine Feed Systems Using CFD Modeling

This study examines the thermal management of the Centennial Restartable Oxygen Methane Engine (CROME) feed system under two propellant tank pressure conditions: 33 psi (227.5 kPa) and 100 psi (689.5 kPa), at a constant liquid methane flow rate of 0.9 lbm/s (0.4 kg/s). Using the Eulerian Single-Phase (ESP) model, the initial test validated experimental data, showing close agreement in total pressure (experimental: 31 psi; CFD: 33 psi) and temperature measurements (experimental: −287.3 °F and −300 °F; CFD: −299 °F and −294 °F) with deviations of 6.4% and ≤4.1%, respectively. For the second test, a simplified Volume of Fluid (VOF) model was used, adjusted for varying liquid-to-gas volume fractions. The best agreement with experimental data was found with 100% GN2, showing a 3.1 psi pressure rise and a 3.3% error. These findings show the importance of improving thermal management and precision control in cryogenic LOX-LCH4 feedline systems for optimal engine performance. Future research will focus on exploring pressures up to the propellant tank’s maximum rated limit of 400 psi.