Large-eddy simulation of hydrothermal flames using extended flamelet/progress variable approach

Abstract

The primary purpose of this paper is to develop high-fidelity combustion models for hydrothermal flames. Based on the flamelet/progress variable (FPV) model, comprehensive real-fluid models are incorporated to treat the thermodynamic and transport properties. To account for the heat loss effects, the FPV model is extended to be non-adiabatic with the heat release damping (HRD) approach. Combined with a presumed probability density function closure, the model is then evaluated in laboratory-scale hydrothermal flames in the context of large-eddy simulation. Results show that the prediction from the FPV model is better than those from the EDM and EDC-MTS models, since it correctly predicts the flame lift-off height as well as the maximum temperature position. The wall heat loss has significant influence on the temperature and species distributions. The use of the non-adiabatic FPV approach improve considerably the predictions of the flame temperature by comparing with the experimental data.