Large eddy simulation of hydrogen autoignition in a preheated turbulent co-flow

The autoignition process of a hydrogen jet into a preheated turbulent air stream is numerically studied. A Progress-variable (PV) model with the turbulence-chemistry interactions modelled using a Presumed Conditional Moment (PCM) closure has been used. Furthermore, the same case is studied using a Finite Rates model without closure for the reaction rate. The PV-PCM model reproduces satisfactorily the physical behaviour found in the experiments, although the model tends to underpredict the autoignition length. The results of the Finite Rates model also capture accurately the autoignition phenomenology observed experimentally and the autoignition lengths are closer to those obtained in the experiment.Peer ReviewedPostprint (published version