Infrared properties of hybrid rocket engine plume were studied by establishing a theoretical model of infrared radiation in 2~12μm wavelength.The pressure

temperature and concentration of each component of flow field were considered as the input parameters.The spectral radiation parameters of the particle were calculated by the Mie scattering model.The thermal radioactive transfer equation was discredited by using the finite volume method(FVM).Finally

the moderate resolution atmospheric transmission (MODTRAN) model was used to calculate the infrared radiation attenuation in the atmosphere.The results indicate that the transmission conditions

height

angle and particle size exert important effect on the distribution of spectrum radiance.The results contribute to providing reference for further research of target tracking and hybrid rocket motors design.