Numerical Simulation Of Three-Dimensional Combustion Flow Field In Plasma Ignition

Plasma ignition technology is a new one been widely using in aviation, shipbuilding industry, power station, petroleum and natural gas transportation and so on. Plasma ignite for engine is a new pattern of portfire which has a especially discharge characteristic and highly discharge energy to increase the reliability of retrofires and extend the concentration limit of retrofires. So many researchers are taking up with studying it.The work process of plasma ignition is that it firstly lights up the start-up oil and form ignition torch to ignite the main oil in the combustor. There are much complicated and exquisite physical and chemical processes when the oil and the air been mixed, which including complex mid-process with cracking and recombining reactions and different reaction velocities. At present for some theories of the combustion are not mature and the partial differential equations are so complicated, it is very difficult to get the accurate flow field distribution. So it limits the combustion theory to design combustion equipment.With the rapid development of computational fluid dynamics and combustion theory and computer application, applying a numerical method to simulate the complicated processes in the plasma ignition is possible. Using numerical simulation can estimate the parameters, which are not easy to measure from experiments, can improve the reliability and reduce the cost. So the numerical simulation is a new pattern way to study the inner mechanism of the plasma ignition.In this paper, on the basis of analyzing comprehensively a lot of relative bibliographies, constituting some basic conservation equations in Cartesian system which reflect the flow law and building and applying many mathematical models of physical and chemical reactions in the plasmaignition: applying KNGk-e two equations turbulence model to calculate the turbulence parameters; applying limited velocity chemical reaction model and multi-step reaction to calculate diffusion combustion model and applying discrete ordinates model to simulate the radiation heat transfer. During the numerical simulation, there are applying the curvilinear coordinates for the complex geometry of the computational field; applying the mixing format to disperse the equations; applying SIMPLEC algorithm method to solve pressure-velocity coupling and applying the multi-grid scheme to obtain converged solution.This article had simulated five states of the steady reaction flow and obtained the turbulent reacting flow field distribution of parameters, including temperature and pressure and turbulent kinetic energy and its dissipation rate and turbulent viscosity and velocity and density and mixture fraction of products. Especially there are many parameters representing the plasma ignition characteristic on the outlet, for example: energy flow and temperature and so on, and study out the related curves. These results are significant to design and improve the plasma ignition.