Radiation Model Development for Combustion Systems

Evolving demand for robust and accurate multi-physics modeling tools for high performance combustion devices is being driven by increasingly complex design, analysis, and simulation requirements, but existing models and their underlying assumptions need to be rigorously examined in light of their intended Air Force propulsion system applications. The production use of coupled multi-physics modules for the prediction of engine performance, reliability, and life cycle management is now becoming feasible as computer software has evolved sufficiently. For Air Force propulsion systems, the operating conditions involve high temperatures and pressures, especially for large scale (e.g., 10X) scramjets and high pressure liquid rockets. At these elevated working conditions, radiation becomes an increasingly important contributor to the overall heat balance, thus further affecting the combustion processes. The proposed research will provide the Air Force with physics-based engineering radiation models for the prediction of high pressure, high speed turbulent reacting flows applicable to hydrocarbon propulsion systems. The fundamental assumptions of the models will be reviewed in comparison to their intended use to ensure applicability, and the models will be validated against benchmark data to establish predictive ranges of accuracy. Application interfaces will also be developed to allow streamlined integration into existing computational fluid dynamics software.