Reactive Large Eddy Simulations (LES) with direct integration of chemistry are presented in this work for the numerical investigation of a novel test bench developed at the Bundeswehr University of Munich. The experimental setup aims to investigate secondary near-wall reactions caused by cold fuel injection into a hot crossflow and it provides measurements of OH-PLIF, OH* and reconstructed wall heat fluxes for comparison with numerical computations. Here the experimental configuration with methane as fuel and an impulse ratio of 10 is investigated. The effect of chemistry is investigated using two reduced chemical mechanisms with 19 and 30 species, respectively. Two meshes including one and three fuel injector nozzles are considered, to investigate the jet-to-jet interaction. Four inlet temperatures for the hot flows are investigated, to estimate the sensitivity of the autoignition length to a variation of the hot inlet temperature. The results show that the autoignition length estimated from the OH and CH2O concentrations is strongly dependent on the temperature of the hot reactants and that chemistry is the driving factor to trigger autoignition in the chosen configuration. A qualitatively good approximation with the experimental autoignition length is obtained with a hot inlet temperature of 1600-1620 K. The numerical wall heat flux does not predict the local peak due to the reaction zone close to the wall, but the order of magnitude of the experiment is reached.    «

Reactive Large Eddy Simulations (LES) with direct integration of chemistry are presented in this work for the numerical investigation of a novel test bench developed at the Bundeswehr University of Munich. The experimental setup aims to investigate secondary near-wall reactions caused by cold fuel injection into a hot crossflow and it provides measurements of OH-PLIF, OH* and reconstructed wall heat fluxes for comparison with numerical computations. Here the experimental configuration wi...    »