Overview and analysis of the experimentally measured throat heat transfer in liquid rocket engine thrust chambers

Abstract

The design of high-performance liquid rocket engines is highly dependent on the management of the heat transfer rate produced by the combustion-gas and entering the thrust chamber wall. In particular, the life of the thrust chamber is mainly limited by the level of temperature and heat flux reached in the most thermally solicited part, which is the throat region. Consequently, experimental data of the hot-gas side heat transfer have been acquired since the 1950s. Such studies have increased over time in order to investigate the effect of different propellant combinations, propellant injector configurations, thrust chamber geometries, and combustion chamber pressures. In the present study, about 500 experimental heat transfer data taken from the open literature and relevant to the throat region are collected, manipulated, and analyzed with the main aim to find simplified rules to evaluate the peak heat transfer. Due to the intrinsic variability of the hot-gas side heat transfer and to the non-negligible measurement errors, the found correlations fit the whole set of experimental data with an uncertainty of up to 60%. However, considering specific propellant combinations, like oxygen–hydrogen or oxygen–hydrocarbons, far more reliable regressions are found.