Study of the Application of Flamelet Models in Combustor with Different Tabulation Methods

In order to improve the knowledge and understanding of the turbulent combustion in aeroengine combustor, flamelet models with different tabulation methods are used to simulate the turbulent combustion in an aeroengine model combustor. The tabulation methods include two sections: One is the construction method of laminar flamelet library that means Flamelet/Progress Variable (FPV) based on diffusion flame and Flamelet Generated Manifolds (FGM) based on premixed flame; the other is the Probability Density Function (PDF) type of reaction progress variable that means δ and β distribution. LISA and KHRT models are employed to model the breakup of liquid film and droplets respectively, and non-equilibrium Langmuir-Knudsen model is employed to model the evaporation of droplets. The breakup distance of liquid film from LISA model is about 4.6 mm, and the droplets diameter decreases rapidly to about 10μm in the downstream of venturi exit and are completely evaporated close to the downstream of dome exit. Compared with the temperature from Coherent Anti-Stokes Raman Scattering (CARS) and Tunable Diode Laser Absorption Spectroscopy (TDLAS), the accuracy of FPV and FGM models is verified, and FPV model has higher accuracy in the locations where flow changes violently and moreover FGM model has higher accuracy in the rest locations. Models adopting β distribution as the PDF of reaction progress variable can improve the accuracy of temperature, and the error of temperature is almost below 5% in primary zone. In addition, it can be described better that the unburned mixture is ignited by the recirculated burned gas by FGM with β distribution, and the PDF type of reaction progress variable has a more important effect than construction method of laminar flamelet library.