Analysis of the Gas-Solid Interphase Fluctuating Energy Interaction in Fluidized Bed

Large-eddy simulation with subgrid-scale (SGS) turbulent kinetic energy model was used for simulated gas turbulence, and second-order moment model was used for simulated anisotropy characteristic of particles. Huilin- Gidaspow drag model was used for simulated gas-solid interphase force. The large-eddy simulation of gas-second- order moment of particles two-fluid model (LES-SOM model) was presented. Based on Simonin gas-solid interphase fluctuating energy second-order interaction model, considering the gas-solid fluctuating energy transfer between SGS turbulent kinetic energy of gas and SOM of particles, the gas-solid interphase fluctuating energy second-order interaction item was proposed, and revised Simonin gas-solid interphase fluctuating energy second-order interaction model is established for LES-SOM model. The simulations compared with Koch model and revised Simonin model were researched for the distributions of gas-solid interphase fluctuating energy with particles concentration. The effects of gas-solid interphase fluctuating energy on concentration and velocity of particles were analyzed, which showed that fluctuating energy had little effect on macro parameters. The effects of gas-solid interphase fluctuating energy on SGS turbulent kinetic energy of gas and SOM of particles were analyzed, which showed that fluctuating energy had significant effect on micro parameters. The simulation results showed that the value of SGS turbulent kinetic energy and SGS energy dissipation was larger with considering gas-solid interphase fluctuating energy second- order interaction item, and the value of SOM was also larger. Compared with the effect of fluctuating energy second-order interaction on SOM of particles, the simulations with revised Simonin model are lower than with Koch model at high particles concentration since revised Simonin model considers the effect of collision dissipation between particles, and higher at low particles concentration since revised Simonin model considers the effect of gas turbulent fluctuation energy to particles movement.