Comparative Study on fractal model and spherical model of fire smoke particles for light scattering

• 1、School of Electronic Science and Applied Physics, Hefei University of Technology
• 2、State Key Laboratory of Fire Science, University of Science and Technology of China

Abstract：It is important to research light scattering from fire smoke particles by numerical calculation. Traditionally, spherical or spheroid models were used to approximate the shape of smoke particles for light scattering calculations. But actually, smoke particles have a similar fractal structure, which is different from spherical structure. Using the discrete-dipole approximation method, the light scattering Muller matrices were computed for the randomly oriented fractal aggregate, as well as the spherical particle with the same volume of aggregate, and then both normalized Muller matrix elements were compared. The results indicate that the angle distributions of the normalized matrix elements 、 and have significant differences between the fractal model and spherical model. We can discriminate spherical non-fire aerosols from smoke particles, using the difference of between fractal model and spherical model.

Keywords： Smoke detection fire smoke particle fractal model spherical model