LES Of Laboratory-Scale Turbulent Jet Flame At High Pressure And High Reynolds Number

As the main energy source of modern human society, the research on combustion is essential and has been developed systematically. The precise prediction for this phenomenon has led to great significance on combustor design, efficiency improvement and pollutant reduction. The experimental research method started from the beginning of 20 th century. Due to the high expense and uncertainty of observation, the development of experiment has been highly limited. As the invention of computer and emergence of parallel computation technique, the possibility of numerical simulation was dramatically increased.High performance computation technique has been applied on the field of combustion research for several decades. The Reynolds-Averaged Navier-Stokes Simulaiton(RANS) was the first industrialized method in numerical simulation. But the incapability of prediction turbulent combustion phenomena accurately has been a major problem of this method. Direct Numerical Simulation(DNS) which involves all the spatial scales and chemical reactions has been proved to precise enough to depict the flow field and combustion procedure. But this simulation strongly depends on the computation facility which makes it hard to perform efficiently.As a relatively new method, the Large-Eddy Simulation(LES) on turbulent combustion emerged as a science only in the 1990 s. LES has already been applied to a variety of combustion problems of technical interest including turbulent combustion flow analysis, prediction of pollutants etc. And this thesis will also concentrate on this method.Different from the pure fluid mechanics research, the addition of chemical model is an essential part of combustion. The interaction between small scale chemical reaction and turbulence will definitely contribute to the complexity of combustion. In this thesis, two different chemistry model, which are Burke-Schumann model and Steady Flamelet model will be employed to deploy the simulation. A new combustion model will be proposed for the planar jet turbulent model due to the result of comparison.