Simulation Research On Optimization Of Distributor And Particle Properties In Gas-soljd Fluidized Bed

Fluidized bed is widely used in energy,chemical industry and other fields because of its advantages of free flow.In order to ensure the uniform distribution of solid particles in the fluidized bed,it is necessary to optimize the distribution plate and particle propeaties.in this paper,the Standard k-ε turbulence model combined with Euler-Euler model is used to simulate a typical two-dimensional flow dynamic fluidized bed.The simulation results are compared with the expeimental data to judge the applicability of the model,Four kinds of distribution plates with openings are arranged at the inlet of the model,and various physical Quantitics are analyzed and compared,so as to determine the optimal distribution plate opening form of the fluidized bed,the effects of different inlet velocity,particle properties and the arrangement of inlet holes on gas-solid two-phase flow were studied.Through analysis and comparison,the research mainly includes the following conclusions:(1)Through the analysis and comparison of the model validation,the Euler-Euler model is selected with Standard k-ε Dispersed turbulence model can well simulate the flow characteristics of gas-solid two-phase flow in two-dimensional fluidized bed.(2)The flow field characteristics and particle distribution characteristics in a fluidized bed with four kinds of perforated gas distributor plates with an opening rate of 10.5%were studied.Compared with the other three working conditiong,the particle volume fraction and velocity non-uniformity coefficicnt of distributor plate are generally smaller than those of the other three working conditions,and the bed expansion ratio is larger,which can make the relative motion between solid particles and gas more stable,Increasing the contact time of gas and solid,and because there is no circulation above the distributor,the problem of particle accumulation and blockage near the distributor can be effectively solved.(3)The inlet velocity of the fluidized bed is 5m/s,the initial filling height of particles is 0.5m,the particle density is 1500kg/m3,and the particle size is 200μm is the optimal inlet velocity and particle properties for a given fluidized bed.(4)Through the simulation analysis of the flow field characteristics and particle volume fraction distribution in the three-dimensional fluidized bed,it is concluded that the centralized arrangement of the gas distributor inlet is better than the decentralized arrangement,which well verifies the simulation results of the two-dimensional fluidized bed.