Abstract
Laser ignition is insensitive to electrical disturbances and is expected to improve the safety of ignition systems by replacing classical electric ignition systems. To evaluate ignition reliability and design a laser ignition system for extraterrestrial missions, it is essential to clarify the ignition threshold in a deep space environment, where the temperature of a spacecraft could be low. The purpose of this study is to clarify the ignition threshold by obtaining the boundary of ignition/no-ignition and to construct a numerical model that simulates the ignition of the ignition charge under low-temperature conditions. The ignition threshold was obtained through laser ignition experiments conducted at -50 to -55°C. The experimental results indicate that the laser power required for ignition is higher at low temperature than at room temperature, with the power ratio ranging from approximately 1.1 to 1.25. The numerical calculations showed agreement with experimental results within 10% for standard temperatures and within 20% for low temperatures. The numerical model was confirmed to be effective for predicting ignition thresholds.
