Gas-liquid Flow Characteristics And Structure Optimization Of Venturi Atomizer

The emission of sulfur dioxide has become one of the urgent problems in the world today.The sulfur dioxide emitted in the flue gas combines with water vapor and oxygen to form acid rain.Acid rain has a serious impact on human ecological environment.The current desulfurization methods in the world mainly include three methods: dry method,semi-dry method,and wet method,and the most widely used method is the limestone-gypsum method.The self-priming venturi sprayer occupies an important position in wet desulfurization due to its own unique advantages.The self-priming Venturi sprayer has an efficient gas-liquid mass transfer efficiency,and does not need to be connected to external energy during injection,which can effectively reduce the cost of desulfurization.And has a very high desulfurization efficiency,therefore,the desulfurization efficiency of self-priming Venturi sprayer research is particularly important.In the desulfurization process of the self-priming Venturi sprayer,its own atomization effect determines the final desulfurization efficiency,and the outlet particle size distribution has become a key indicator to measure its atomization effect.In the atomization process of the self-priming Venturi atomizer,the existing simulation results do not unify the two atomizations,and the initial conditions of the second atomization use empirical formulas,which inevitably produce a certain deviation from the actual atomization process.In addition,the research on the particle size distribution of the self-priming Venturi sprayer is mainly focused on the particle size distribution of the outlet,and the particle size distribution inside the self-priming Venturi sprayer has not been studied.This paper uses the VOF-DPM coupling model in Fluent to unify the primary atomization and secondary atomization in a complete simulation process.The atomization process simulation of the self-priming Venturi sprayer can be more close to the actual atomization process.The research shows that the particle size of the outlet of the self-priming Venturi sprayer will decrease with the increase of the inlet pressure.In addition,the particle size distribution on the different sections of the diffusion section of the self-priming Venturi sprayer was studied,and it was found that the particle size distribution on the section of the diffusion section at different distances from the throat experienced a decrease and then increase.On the upper and lower half areas of different sections of the Venturi sprayer,the particle size distribution is not uniform.The average particle size of the upper half area is significantly smaller than the average particle size of the lower half area.The possible reason for speculation is that some large liquids The drop will move to the lower half of the area under the influence of gravity,resulting in the phenomenon that the particle size of the lower half is significantly larger than that of the upper half.In the end of this paper,the structure of the self-priming Venturi sprayer was optimized according to the existing problems.By adding an air inlet at the bottom of the diffusion section,the liquid film deposited on the bottom wall of the diffusion section was provided with kinetic energy to enable it to return to Participating in atomization to the center of the diffusion section,the final result shows that the new structure of self-priming Venturi sprayer can effectively reduce the amount of liquid film deposited on the bottom of the diffusion section,and on different sections of the self-priming Venturi sprayer diffusion section,The particle size distribution in the upper and lower half is more uniform,and there is no obvious increase in the particle size of the droplet on the cross section of the diffusion section close to the outlet.