Optimization of Cooling Channel for Spark Plug Based on Conjugate Heat Transfer Simulation

Abstract

Air cooling channel is very important to avoid the ablation of ignition spark plug by reducing the temperature on the end face, and thus increase the service life of the spark plug. For a typical aero-engine ignition spark plug, coupled simulation model describing the flow in the air cooling channel as well as the heat transfer overall the spark plug has been established with a CFD software. Orthogonal experiments have been performed to analyze the influence of the design parameters on the air flowrate and end surface temperature On the basis of orthogonal experiment, the cooling channel is optimized by multi-factor analysis of variance The results demonstrate that: (1) The most important issue that influence the overall flowrate in cooling channel and the maximum temperature on the ignition end face is the number of holes on end face, and second one is the outlet diameter, while the influence of inlet diameter is not significant. (2) There is a better structural design for the cooling channel of the spark plug. The optimized air cooling channel increases the volume flow rate by 52.21% compared to the original scheme, which helps maintain the maximum temperature of the ignition end face of the spark plug below 368.2°C.