Empirical Modeling of Electrical Discharge in an Inert Medium at High-speed Flows
Energy discharge models have been used to gain insights into the spark discharge process and early flame kernel development in spark-ignition engines. However, the existing models are reported to be applicable for a limited range of gas pressures and flow fields. This study aims to evaluate these models and propose an improved one to predict the spark ignition at pressurized conditions up to 45 bar and high-speed flows up to 32 m/s. The model captures the spark discharge behavior that has been observed experimentally in an optically accessible constant-volume combustion vessel. This includes discharge characteristics and the occurrence of the spark blowouts and re-strikes. Results indicate that the voltage and current waveforms of the spark discharge are correlated to the flow velocity across the spark plug gap. Further investigations were performed to study the stretching rate of the spark channel under the high crossflow.