Applications of Ceramic Matrix Composites in Liquid Rocket Propulsion

Abstract

In this paper, the applications of ceramic matrix composites (CMCs) in liquid rocket engines (LRE) are investigated from the perspective of several years’ experience with volume production of hot-section CMC components for air-breathing gas turbine engines. SiC/SiC CMC applications are proposed that offer the best advantages, and immediate developments needed to facilitate the application of CMCs in LREs are identified. The technology readiness, characteristics, advantages, and disadvantages of CMCs in liquid rocket engines are discussed. A performance model of a generic gas generator cycle rocket engine indicates that engine Isp could increase by up to 5.5 seconds if the turbine inlet temperature could be raised to 2,200 K, a capability that may be enabled with CMCs. For a typical mission consisting of a 5-minute burn operating at 890 kN thrust, this results in a reduction of consumed propellant of 2,040 kg. A separate thermostructural analytical study was conducted using a representative regenerative cooling channel made of CMC subject to realistic environments. Results indicate that CMCs may outperform traditional materials given the expected range of conditions, particularly over repeated cycles, and at significantly lower weight.