Experimental and numerical methods for radiative wall heat flux predictions in paraffin–based hybrid rocket engines

Abstract

The paper is intended to present both experimental and numerical approaches for estimating the heat exchange through thermal radiation towards the walls of lab–scale paraffin–based thrust chambers. Two firing tests of a lab–scale gaseous–oxygen/paraffin–wax hybrid rocket engine have been performed to apply such methods. In particular, the radiative wall heat flux has been evaluated by both spectroscopic measurements and discrete transfer method computations. Details of such approaches are given together with results achieved. The significant gap between experimental and numerical estimations suggested further investigations of influencing processes, whose main outcomes and lessons learned are critically discussed.