A Quasi-2-D Model for the Prediction of the Wall Temperature of Rocket Engine Cooling Channels

Abstract

A simplified quasi-2-D model is developed to study the coupled problem of coolant flow and wall structure heat transfer in the cooling channels of an liquid rocket engine thrust chambers. This model is based on one-dimensional governing equations for coolant mass conservation and momentum balance, and on a two-dimensional governing equation for coolant energy balance. The energy balance equation is coupled to the wall heat transfer balance in the radial direction. The turbulent thermal conductivity, fluid skin friction, and coolant-wall heat transfer coefficients are evaluated by semiempirical relationships provided in the literature. This model, which is suited to high aspect ratio cooling channels, permits fast prediction of both the coolant flow evolution and the temperature distribution along the whole cooling channel structure. Validation of the model is first carried out by comparison with straight channel solutions obtained with an experimentally validated CFD solver. Then, further validation is carried out by using the quasi-2-D model for the analysis of a regeneratively cooled rocket engine thrust chamber. Results show good agreement with available data of maximum wall temperature and coolant pressure drop.