Research On Numerical Simulation Of Synthesis & Growth Of Titania Nanoparticle

Considering the superior characteristics that nano-material has performed, the preparation methods is getting more attention. The CVD method is one of the many methods to produce the nano-material, which could get high purity and better thermal stability particles. This method could be widely used in industry. Commodities such as carbon blacks, pigmentary Titania are typical products of this method.In this paper, the simulation of the process of particle growth integrated the basic theories of fluid and particle dynamics.Using the commercial CFD-code FLUENT, the simulation of the flame is calculated and the flame structure feature is obtained by analyzing the results under difference cases, which provides good foundations for the next section. The combustion reaction occurs in a single step, the calculated results show that the RNG k-εturbulent model produces reasonable predictions for the temperature field and the shape of the flame with the Non-Equilibrium wall function in comparison with other method, the reaction velocity is calculated with eddy-dissipation model.Then the math model of particle dynamics complied with C is calculated by FLUENT &it's UDF. The process of nucleation and dilution is imported into collision model. The process of nucleation is supposed that all the reaction products of TiCl₄ transform to free molecule monomers which are the primary particles and the primary particles grow in the flame. Considering the small size of the particles, their motion obeys to the rule of gas motion and the effects between particle and gas are neglected.The simulation results show that the prediction matches the experiment. At the same time, the effect of the fame field to the particle is analyzed. It indicates that temperature is the dominant factor in the process of particle. The residential time affects the particle diameter as well. The dilution restrains the velocity growth.