Fuel and Combustion

Fuel and Combustion

Large Eddy Simulation of Fire-induced Flow behind a Combustible Vertical Wall

Authors
Faculty of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran
Abstract
Large eddy simulation (LES) is performed to investigate oscillation behavior and time-averaged values of the fire behind a vertical wall. One-Equation sub-grid scale (SGS) model is used for turbulent closure. The combustion is assumed to be non-premixed. Also, modified eddy dissipation concept (EDC) and discrete ordinate methods (DOM) are used for incorporating combustion and radiation, respectively. The models are applied for the total heat release rate (HRR) of 36 kW and 54 kW. The numerical results are validated against experimental measurements. The time-averaged temperature and velocity are in a good agreement with the experiments. Generally, the accuracy of the predictions reduces considerably near the wall surface. The oscillating behaviorsof the simulated quantities show the three-dimensional and asymmetric nature of the induced flow.In addition, the amplitude of the vertical velocity fluctuation reduces with increase in normal distance from the vertical wall. This fluctuation increases with increase in the height from the area where the fuel is burning.
Keywords

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