Fundamental Characteristics of a Cylindrical Rotating Detonation Combustor with Solid-Fuel Walls

A rotating-detonation combustor (RDC) is subject to high heat loads attributable to high temperature gases and complex flow patterns. Ablator materials such as carbon-carbon composites suffer from erosion in a detonation region. Therefore, a gas–solid multiphase RDC (GSM RDC) system, which recovers heat loads by substituting the RDC wall with a solid fuel, is proposed. In this system, it is hypothesized that the detonation wave propagates as the solid fuel is consumed, causing the shock wave to interact with vaporized gas. This study investigated how the gasification of solid fuel affects detonation structure, combustion, and propulsion performance. Combustion tests are conducted in a cylindrical RDC with high density polyethylene (HDPE), oxygen, and ethylene. The combustion structure observed using a high-speed camera reveals that vaporized gas combusts along the chamber wall surface. The thrust in the RDC with the HDPE-wall configuration is 10% higher than that of the stainless steel (SS) wall. Propulsion performance can be predicted with [Formula: see text] accuracy by considering additional mass and modifying the equivalence ratio. These findings demonstrate the effect of vaporized gas combustion and help to clarify the interaction on a time-average basis. Thus, this combustor realizes a propulsion system for ablation cooling and thrust enhancement.