Numerical Calculation on Infrared Characteristics of the Exhaust Plume Outside Axial-Symmetrical Nozzle

摘要

For mastery of infrared radiation spectral characteristics and intensity distribution of exhaust plume of an axial-symmetrical Nozzle, this paper used software Fluent6.3 to simulate the 3-D exterior flow field of the axial-symmetrical nozzle, and obtained the data of the flow field such as temperature, pressure and density, and established the columniform area of computing infrared radiation according to the characteristic of the axial-symmetrical nozzle plume. Then by the finite volumetric method(FVM) and the narrow band model of gases infrared radiation, the spectral characteristic and the total intensity distribution in 3?5m of exhaust plume infrared radiant were calculated. The results show that the infrared radiation intensity distribution is axial-symmetrical, and the infrared radiation intensity is the feeblest in axial direction and is stronger in p/6?p/3 direction, meanwhile, two peaks of plume infrared radiation emerge in 2.7m and 4.3m, and the infrared detector by 4.3m is in favor of detecting an aircraft.