Numerical Simulation Of Radiation Characteristic Parameters Of Aggregated Particles

The multi-particle aggregates participate in such heating, cooling and otherprocesses in the nature and production practices. And the multi-particleaggregates applied in the power machinery, chemical metallurgy, aerospacetechnology and many other industrial sectors importantly. Therefore, the study ofheat transfer characteristics of the multi-particle aggregates is of greatsignificance.In this paper, numerical simulation is used to simulate and analyze theradiation characteristics of the multi-particle in the different scale parameter andporosity with two geometries arrangement which include spherical geometricarrangement and ellipsoidal geometric arrangement based on GMM theory，DDA method and T-matrix method first. Then, the T-matrix method is applied tocalculate the radiation characteristics of the random arrangement of the particlesagglomerate, the DDA method is used to calculate the radiation characteristics ofthe cylindrical particles agglomerate. The radiation characteristics of the multi-particle aggregates obtained by the three different numerical simulation arecompared, respectively. Numerical simulation is used to simulate and analyze theradiation characteristics of the multi-particle in the different scale parameter andporosity with the determination of the geometry based on GMM theory DDAmethod and T-matrix method, and study the impact of various factors on theradiation characteristic parameters of the multi-particle aggregates.The studies have shown that the particle has larger influence on others whenthe scale parameter and porosity are smaller. With the scale parameter, theporosity increases, the interaction between the particles decreases. The number ofthe multi-particle aggregates influence the radiation characteristics in the smallerscale parameter, too. The relative deviation is only concerned with the number of particles when the scale parameter is large enough. Similarly, the influence of theshape of the multi-particle aggregates is larger when the scale parameter andporosity are smaller.For the T-matrix method, when the parameters are the same as ones of theGMM theory, the results are consistent; for the DDA method, in the establishedmodel range, the results with those of the other two methods have remained thesame, however, the relative deviation is slightly large.