A General Solver Framework for Radiative Heat Transfer Models in Combustion Systems

Modern combustion systems such as liquid rocket engines and gas turbines are characterized by high operating pressures and temperatures due to increased power-density. Thermal radiation has significant impact on both heat fluxes at the wall and on physical phenomena controlling the combustion process at these conditions. Coupling between radiation, turbulence and chemistry can have a large effect on the net radiative fluxes and heat loss from the flames. The objective of this SBIR project is to develop a general, computationally efficient, high-accuracy numerical tool to model radiation in combustion systems. CFDRC and University of California, Merced will assess the existing radiative transfer equation (RTE) solution methods as well as radiative property models for participating media including combustion gases and particulates such as soot. In Phase I, the various RTE solver methods and radiative property models will be assessed in canonical configurations such as jet flames and complex configurations such as scramjet combustors and supercritical rocket engines. Radiation modeling tools will be analyzed for their computational cost, accuracy, and strengths and weaknesses for Air Force relevant flow and combustion regimes. In Phase II, the model improvements will be implemented and validated and a stand-alone RTE solver framework will be built and demonstrated on CFD codes of interest to the Air Force.