Numerical Simulation Of Turbulence Diffusion Flame Based On One-dimensional Turbulence Model

The actual fire is a turbulent combustion process. While the actual turbulent combustion is a nonlinear process which turbulence and complex chemistry strongly coupling. The couple of turbulence and complex chemical reaction brings increased rigidity and a large amount of calculation, so the theory and simulation of couple turbulence and complex chemical become a challenging work. The DNS simulation of turbulent combustion can reach Komogrov standard, and it can capture small vortex structures and turbulence information in turbulent flow, but the multidimensional coupled turbulent and complex chemical simulation calculation cause large scale of calculation, so it is difficult to implement. Furthermore, the couple of complex chemistry and laminar flame cannot reflect the turbulence combustion characteristic. Therefore, the turbulence combustion simulation coupled with complex chemical needs a feasible and effective numerical simulation platform. One dimensional turbulence model (ODT) simulation not only has a high precision simulation of turbulence combustion, but also the computational cost of one-dimensional scale is also in the affordable range. This paper establishes the large-scale model of ODT parallel platform and simulates and analysis of two methyl phosphoric acid methyl ester (DMMP) inhibitory effect on propane turbulence diffusion flame.First, this paper introduces the mechanism and numerical solution method of the ODT model, and applies the model to analyze the influence of H2O/CO2/N2on syngas flame. We verify the validity of the ODT model through compared one case simulation results with the America Sandia national laboratory experiments results. The simulations are performed at a higher Reynolds number, we numerically analysis the effects of different diluents on the flame structure, temperature and NOx emission of the syngas flame as well as extinction and reignition phenomena. The simulation results show that the diluent CO2cause the maximum degree reduction of the syngas flame temperature, the emission of NOx and caused the maximum flame extinction.Secondly, because the simulation of turbulence combustion coupled with complex chemical realization needs strong computing capability and large memory, so it requires using parallel compute to realize this simulation. In this study, the parallel computing system and its algorithm are studied. Using high performance of Linux system and the MPI programming platform to caculate chemical reaction module which needs to spend a lot of time in the ODT model has saved the calculation time effectively. Using the parallel technology to simulate ethylene jet flame and compared the results with David et al to prove the validity of ODT parallel calculation.Finally, the P-containing additives (DMMP) inhibition effects on propane turbulent nonpremixed flame are performed using the ODT large scale computing platform. The simulation results show that after adding the extinguishing agent DMMP, the propane flame temperature, the flame radicals of OH and O are also reduced. When the DMMP amount reached300ppm, the extinction probability of the propane turbulent jet flame rises from0.5to0.6. It can be pursued after analysis the phosphorus decomposition that HOPO2and HOPO can be quickly conversion through PO2. And in these catalytic reactions, if the flame radical H or OH substituted by some other species such as methanol or other stable component, which also can cause the propane flame extinction.The main contribution of this paper is the establishment of large-scale ODT model forecasting platform. There are interactions between the strong turbulent flow and chemical reaction process in the turbulent combustion. However, the traditional study of complex chemistry is based on laminar flow without considering the effect of turbulence on the chemical reaction. Therefore, this paper simulation analysis and discusses the inhibition effect of DMMP under the turbulent and complex chemical coupling condition. These results also provide the numerical simulation research foundation for the fire extinction, reignition and other typical turbulence phenomena.