Turbulence-Chemistry Interaction and Heat Transfer Modeling of H2/O2 Gaseous Injector Flows

Reliable prediction of rocket injector flows introduces significant challenges associated with the complex physics involving recirculation, turbulence, scalar mixing, chemical reactions and wall heat transfer. This work is aimed at assessing the importance of turbulence-chemistry interaction and non-equilibrium effects in experimentally characterized single and multi-element injector flows. By examining the different chemistry models (laminar finite rate, assumed PDF with either flamelet or equilibrium assumption), it was found that for both cases investigated, chemical non- equilibrium is insignificant while substantial turbulence-chemistry interaction is observed. A zonal wall treatment was developed based on a blend of SST low-Re turbulence wall treatment and law- of-the-wall, showing improved predictive capability. A heat flux extraction method was also proposed to estimate heat flux results from adiabatic flamelet model under the consideration that wall heat loss is small compared to the overall energy generated by chemical reactions.