Evaluation of chemistry models on methane/air edge flame simulation

Abstract

The integration of chemistry into a numerical fully compressible solver is carried out in this study using three models: detailed chemistry, fully tabulated chemistry (CTC) and a model coupling both approaches called HTTC, for hybrid transported-tabulated chemistry. With HTTC major species are transported while most minor species are tabulated. As minor species are no longer transported with the flow, the time step is close to the values usually encountered for non-reactive flows, far beyond what is found in detailed chemistry. The performance of HTTC for reproducing the dynamics of a methane/air edge flame featuring a very strong mixture fraction gradient is also investigated. The results agree favorably with the reference case simulated with detailed chemistry unlike the CTC model which is unable to predict the topology of the flame. Finally, the shape of the flame, the flame speed and the flame stabilization height are reasonably well captured with HTTC with a calculation cost divided by about 5 compared to the reference case.