Analysis of influence of secondary flow in sand sampler on the collecting range of sand
Secondary flow is a common physical phenomenon in engineering practice,which is a secondary flow relative to the mainstream.In order to study the influence of secondary flow on airflow velocity and different particle sizes of sand particles in a sand sampler,this paper uses a combination of numerical simulation and experimental verification to analyze the flow field characteristics before and after secondary flow is weakened,taking the wind-sand separator of the shunt-hedging and multi-stage expansion sand sampler as the research object.The research results indicate that before secondary flow is weakened,sand with a particle size greater than 0.083 mm are completely collected,while sand with a particle size less than 0.083 mm are mostly collected.After secondary flow is weakened,the distribution range of high-speed airflow becomes larger,and the flow field seems to become unstable.The airflow velocity inside the exhaust pipe significantly increases,and only sand with a particle size greater than 0.12 mm are completely collected,and the range of sand being completely collected is significantly reduced.