The first-order sub-grid Conditional Moment Closure (CMC) model within the framework of Large Eddy Simulation (LES) will be introduced and its applicability in predicting localized and global extinctions in gas turbine flames will be discussed. Firstly, a globally fuel-lean swirling-stabilized methane flame in a gas turbine model combustor approaching blow-off condition is investigated with LES/CMC. The results show that the time-averaged velocity, mixture fraction, temperature, major species and OH mass fractions and the heat release location are predicted well in the simulations. The transient behaviors of the flame root, near the burner exit, due to localized extinction are discussed. Secondly, the blow-off dynamics in a model gas turbine combustor experimentally measured in Cambridge are simulated with LES/CMC. The accuracy of the CMC model in predicting the critical blow-off condition is confirmed over a wide range of operating conditions. The evolutions of localized extinction, reactive scalars and scalar dissipation rate during the blow-off process are analyzed. Finally, further discussion about the CMC combustion model for modelling extinction dynamics and its potential for other combustion applications will be provided.
Dr Huangwei Zhang received his Bachelor’s degree in engineering mechanics and Master’s degree in fluid mechanics in 2007 and 2009, respectively from Beihang University. He worked as a research associate in the State Key Laboratory of Turbulence and Complex Systems, Peking University from 2009 to 2011. He obtained his PhD degree in energy and combustion from the Department of Engineering, University of Cambridge in 2015. He then stayed on in the University of Cambridge to take up a postdoctoral research associate position on multiphase combustion. In 2017, he started his career as an assistant professor in Department of Mechanical Engineering, National University of Singapore (NUS). He is also a co-investigator in Cambridge Center for Advanced Research and Education in Singapore (CARES).
Dr Zhang’s current research interests include: combustion theory and modelling, turbulent combustion modelling (based on CMC and MMC models), multiphase combustion, detonation and rotating detonation engines. He was awarded Professor Allen T Chwang Fluid Mechanics Scholarship, Cambridge Overseas Trust Scholarship, Dorothy Hodgkin Postgraduate Awards, and received the Postdoctoral Research Fellowship from the Centre for Turbulence Research at Stanford University. He was also selected by the UK Pilot Centre for European Research Community on Flow, Turbulence and Combustion (ERCOFTAC) as a finalist for the Osborne Reynolds Research Student Award due to the excellence of his PhD research. He is a member of the Combustion Institute.