题目：Large Eddy Simulation of Turbulent Diffusion Jet Flames Based on Novel Modifications of Flamelet Generated Manifolds

时间：2024年9月22日 13:30-14:30

地点：机械与动力工程学院 F310会议室

邀请人：夏溪 副教授（航空动力研究所）

Biography

Professor Sadegh Tabejamaat is the head of the Amirkabir Combustion Lab at Amirkabir University of Technology in Iran. He obtained his Ph.D. in Aerospace Engineering from Tohoku University in Japan in 1998. He was a visiting professor at the University of Toronto from 2007 to 2008, and was the Head of the Department of Aerospace Engineering of Amirkabir University of Technology between 2014 and 2018. He presently serves as the Chair of the Iran Combustion Society. Professor Tabejamaat’s research focuses on experimental and numerical studies of flame dynamics, with a special interest on hydrogen combustion and MILD combustion and their applications in industrial combustors. 

Abstract

A novel mathematical definition is introduced to achieve the inherently monotonic progress, namely Absolute Cumulative Variation (ACV). The classical progress variable is defined as a weighted summation of species mass fraction while weight factors are determined in the ad-hoc procedure. The ACV definition presents the systematic method to generate a fully look-up table appropriate for the vast combustion applications. This method utilizing the preferential diffusion effects and has the potential to predict the autoignition delay time as well as pollutant concentrations, such as CO and NO. The flamelet-generated manifold is coupled with ACV to make the ACV-FGM method. Furthermore, the Variable Ignition Mixing Layer (VIML) is presented as a modified method to generate a 2-D look-up table for the multi-inflow streams as well as varying composition reactants at the domain boundaries. This model helps to reduce the size of the look-up table for complex inflow boundary conditions and computational cost as well. The validation process for the ACV-FGM and VIML methods includes a one-dimensional laminar flame along with large eddy simulation (LES) of the Sandia piloted flames D, E, and F, and Delft Jet-Hot Coflow (DJHC) burner as lifted turbulent jet flame. The results indicate the ACV-FGM method successfully predicts the autoignition delay time, lift-off height, temperature rise as well as spices mass fractions and pollutants. Moreover, The VIML method appropriately reproduces the variation of chemical compositions and temperature at the domain boundary using the 2-D look-up table.