Analyzing the ultraviolet radiation of hydroxyl radical chemiluminescence in a motor plume using improved local equilibrium method coupled with Monte Carlo method

Because of high false alarm rate of the infrared equipments, ultraviolet warning technology arouses greater attention. In this paper, a method of calculating hydroxyl (OH) radical chemiluminescence in a motor plume is put forward combining the improved Local Equilibrium method with the Monte Carlo method (iLEMC). The simulation method is validated by testing a hydrogen-oxygen engine. Meanwhile, comparison is made between the local equilibrium method and the improved local equilibrium method. The results suggest that the iLEMC method is accurate and efficient and the ultraviolet radiation of the plume is mainly from the OH radical chemiluminescence. These conclusion and results will greatly helpful for analysis, design and optimization of the UV warning systems and also the technique of UV stealth for aircrafts.