Laser Detection Of Toxic Pollutant Gases Simulation Study

Make use of the Monte-Carlo simulation, the physical of the laser detect the hazardous pollution gas is simulated, and the characteristics of the laser scatter in the hazardous gas of DMMP are researched, then the gas particles are detected and identified in the paper. The theory model of the laser transmission in the hazardous gas of DMMP is constructed on the basis of the Monte-Carlo simulation theory, and then using the theory of laser scatter, the variation of fluence rate and the diffuse reflectance with space and time are simulated when the two laser beam with different distribution (the flat beam and the Gaussian beam) incidences the DMMP. The variation of diffusive intensity with delay time are compared when the radius of gas particles are different, we conclude that the characteristics of gas particle's scatter are influenced by the radius of particles. In order to research the transmission of laser in the DMMP, the solution of the diffusion equation in frequency domain is set up. Through Fourier transform, the time-resolved reflectance is computed. The time-resolved reflectance between the solution of DMMP diffusion equation and Monte-Carlo simulation are compared. The result shows that the result of diffusion equation accords with the Monte-Carlo simulation.