Research On Gas Solid Flow And Solid Particle Erosion In Butterfly Valve

As an important component in the field of pneumatic conveying to control the flow and switch on or off the pipeline,the butterfly valve will be directly impacted by particles and form serious erosion.Under different opening,the gas flow field in the pipeline of butterfly valve will be different,which will change the trajectory and distribution of particles,making the erosion distribution of disc and pipe wall different.The diameter of particles and the placement of the butterfly valve will also affect the particle distribution and gas flow field in the pipeline,which will affect the erosion distribution.Therefore,combining the experiment and the numerical simulation,this paper studied the gas-solid two-phase flow and erosion distribution in butterfly valve by changing the diameter of particles,and the opening and the placement methods of the butterfly,so as to provide reference for the optimal design of butterfly valve.The main contents of this article are as follows.(1)Study on gas-solid two-phase flow and erosion characteristics in butterfly valve with different opening and particle diameter.The erosion characteristics test platform and measurement device of square tube butterfly valve were built,and the erosion test experiment was carried out.The erosion equation was added to the calculation according to the CFD-DEM theory.The gas-solid two-phase flow and erosion of DN50 butterfly valve with different openings were calculated.The particle diameter ranged from 100μm to 300μm.The results showed that the simulation results were in good agreement with the experimental results.The downstream pipeline of butterfly valve formed very complex vortices due to the gas flow separation.The particles in the pipeline will collide with the wall for many times.The erosion laws of the wall were different under different openings,and the leading edge of the valve disc suffered a very serious erosion.(2)Study on gas-solid two-phase flow and erosion characteristics in butterfly valve under different placement modes.The effects of different placement methods on particle distribution and erosion characteristics were studied.The results showed that when the opening angle of the butterfly valve was 30°,the "—" shaped particle flow and erosion marks was formed at the bottom of the pipe for the placement of horizontal valve stem.An "X" shaped particle flow and erosion marks was formed at the bottom of the pipe for the placement of vertical valve stem.The particles formed upward movement in the downstream pipeline for the placement of vertical pipe.When the opening angle of the butterfly valve was 60°,there was a large area of erosion on the front disc under all three placement methods.When the opening angle of the butterfly valve was 90°,the erosion on the back disc and front disc was almost symmetrical.From the particle accumulation before disc,the maximum erosion mass of the disc,and the erosion rate on the upper center line of the pipeline,the placement of horizontal valve stem is the best method.