Supercritical Heat Transfer of Cryogenic-Propellant Methane in Rectangular Engine Cooling Channels

Supercritical fluid flow and heat transfer phenomena have important applications in the regenerative engine cooling technology in aerospace engineering. In this paper, three-dimensional numerical analyses have been conducted for turbulent supercritical heat transfer of the cryogenic-propellant methane flowing in a rectangular engine cooling channel with asymmetric heating on the top channel surface. Effects of the operational pressure, wall heat flux, and channel geometric ratio on supercritical heat transfer processes have been investigated. Numerical results indicate that the operational supercritical pressure and wall heat flux would exert significant influences on supercritical heat transfer processes through their strong effects on thermophysical property variations. Heat transfer deterioration phenomenon could occur during a supercritical heat transfer process, owing to property variation anomaly near the pseudocritical temperature at a near-wall zone. Increasing the operational supercritical pressure would alleviate heat transfer deterioration. In present numerical studies, it is found that a shallow cooling channel performs well for supercritical heat transfer but suffers severe pressure loss. The Bishop heat transfer correlation is tested to be applicable for supercritical heat transfer predictions of the cryogenic methane under certain conditions.