Numerical Simulation on the Laser Induced Oxygen Spark under Different Ambient Conditions

As a new type of ignition technique, laser induced spark ignition can be widely used in the ignition system of internal combustion engines and aero-engines. In this paper, laser induced oxygen spark evolution has been numerically studied with a two-dimensional, unsteady, multi-components and time-accurate model under different ambient temperatures and pressures. The chemical kinetics between species has been considered. A commercial software Fluent is used to solve the problem. Results show that both ambient conditions have great effect on the maximum temperature and maximum pressure of oxygen spark initially, but the effect decreases with time going on. The maximum velocity and maximum electron number density are also prominently influenced by ambient conditions. For the relationship between shock wave radius and time, ambient temperature plays an important role while ambient pressure is insignificant. These results above will be the foundation for the applications of laser induced spark ignition in the future.