Study Of The Extinction Performance Of Artificial Bioaerosol

In recent years,with the continuous development of optical detection systems and guided weapons,the interference ability of traditional matting materials to these weapon systems has decreased significantly.As a new direction of the development of matting materials,artificial bioaerosol has been proved to have significant extinction performance.However,the study of its extinction performance in practical application environment is not sufficient.The effects of environment on its broadband extinction performance have not been studied.The actual attenuation has not been analyzed in combination with the extinction performance and the floating performance in various environments.This paper focuses on the above issues and conducts research from three aspects:(1)Aiming at the problem of broad working band of the targets in practical application,the optical band(0.2?14?m)extinction performance of artificial bioaerosol has been calculated and the relationship between extinction performance and several factors of bioaerosol has been analyzed.It is found that the complex refractive index determines the extinction performance of aerosols in different bands.Increasing the radius of original particles and decreasing the porosity of agglomerated particle can enhance the broadband extinction abilities of bioaerosol.The structure details and the number of original particles in an agglomerated particle have little impacts on the broadband extinction performance of bioaerosol directly when the porosity is constant.(2)Aiming at the problem of environmental diversity in practical application,for extinction performance,the effects of relative humidity on the broadband extinction performance of artificial bioaerosol have been studied.The simulation results and experimental datas from a smoke box experiment show that as the relative humidity values above 70%,artificial bioaerosol shows greater broadband extinction abilities with the increase of humidity.The range of the extinction performance enhancements is determined by the spectral absorption coefficient of artificial bioaerosol.(3)Aiming at the problem of environmental diversity in practical application,for floating condition,a combined model of "Sedimentation-Diffusion" for various environments is established to simulate the bioaerosol floating condition.The results show that the floating performance of artificial bioaerosol is significantly affected by environmental factors,under the same release conditions,the effective extinction area size and the variation trend of it are determined by two factors: atmospheric stability and wind speed.The main innovations of this paper are as follows:(1)The relationships between several factors of bioaerosol and the broadband extinction performance of artificial bioaerosol are analyzed and the conclusions are applicable to the extinction performance analysis of all particles with condensed structure.(2)The variation model of artificial bioaerosol extinction performance with environmental humidity factors is established and the extinction performance of several typical humidity conditions is analyzed.(3)A combined model of "Sedimentation-Diffusion" is established for the artificial bioaerosol,and the floating performance of bioaerosol is studied under various environmental conditions.