Numerical Simulation Of Gas-solid Two-phase Flow In Spouted Bed Under Swirling Effect

Spouted beds is widely used in many fields today,as an efficient gas-solid contactor,it is used in particle drying,coating,combustion and gasification of waste,chemical reaction,pyrolysis,etc.With the deepening of research on spouted bed technology,researchers from different countries have also proposed many different spouted bed structures.For example: the jet spouted bed,guide tube spouted bed,multi-nozzle spouted bed,spouted fluidized bed,etc.These studies are based on several conventional spouted beds,but few people add cyc lone techniques to spouted bed for research.We all know,the main reaction in the spouted bed is concentrated in the annulus region,at the same time,due to the large accumulation of particles and the high density in the annulus region,the movement speed of the particles is relatively small,and particles lack of lateral movement.This shortcoming affects the processing efficiency of particles in the spouted bed.In this paper,we add a cyclone to the spouted bed,hoping to improve this shortcoming of the spouted bed.In this paper,the gas-solid two-phase flow law in a spouted bed equipped with a cyclone nozzle is simulated.We simulate the gas-solid two-phase flow law in a spouted bed by selecting different sizes of cyclone nozzles.First,we change the blade tilt angle of the cyclone,and select the cyclone blade tilt angle to be ?=86°,?=80°,and ?=76°.The study found that when ?=86°,the gas kinetic energy loss in the spouted spout bed is relatively small,the lateral disturbance of the particles is larger,the radial velocity of the particles is larger,the gas turbulence energy in the bed is greater,and the flow field uniformity of the particle velocity in the bed is the highest.O n the other hand,the total pressure drop in the cyclone spouted bed is larger than that of the conventional spouted bed.Further,we change the inlet angle of the cyclone to study the gas-solid two-phase flow law in the spouted bed with different inlet angles of cyclone.We set the inlet angle of the cyclone to ?=60°,?=45° and ?=30° for numerical simulation,after analysis,it is found that when ?=45°,the particle concentration curve in the spouted bed is better,the cyclone effect is better,and the radial velocity of the particles is larger.That is,when ?=45°,the cyclone blade has less obstructive effect on the inlet gas,and has larger disturbance effect on the particles.The gas turbulence energy between particles is the most intense,and the flow field uniformity of the particle velocity in the bed is the highest.Finally,we explore the influence of different gas flow distribution of cyclone on the gas-solid two-phase flow law in the spouted bed by changing the ratio of the inner and outer diameter of the cyclone.We found that,when ?=0.526,particle volume fraction and particle velocity are batter than other kinds of cyclone spout beds.When ?=0.526,the gas turbulent energy in the spouted bed is the largest,and the flow field uniformity of the particle velocity is better.