Coupled Heat Transfer Analysis in Regeneratively Cooled Thrust Chambers

A computational procedure able to describe the coupled hot-gas/wall/coolant environment that occurs in most liquid rocket engines and to provide a quick and reliable prediction of thrust-chamber wall temperature and heat flux as well as coolant-flow characteristics, like pressure drop and temperature gain in the regenerative circuit is presented and demonstrated. The coupled analysis is performed by means of an accurate CFD solver of the Reynolds-Averaged Navier-Stokes equations for the hot-gas flow and a simplified quasi-2D approach, which widely relies on semi-empirical relations, to study the problem of coolant flow and wall structure heat transfer in the cooling channels. Coupled computations of the Space Shuttle Main Engine Main Combustion Chamber are performed and compared with available literature data. Results show a reasonable agreement in terms of coolant pressure drop and temperature gain with nominal data, whereas the computed wall temperature peak is quite closer to hot-firing data than to the nominal value. © 2012 by B. Betti, M. Pizzarelli, F. Nasuti