Research On The Influence Of The Restrictive Structure Under The Sand Outlet On The Performance Of The Cyclone Separator

Under high pressure conditions,the bottom sand outlet of the cyclone separator is different from the free sand under normal pressure conditions.It must be equipped with a certain restrictive structure,such as a sand collecting drum.The amount of sand collected in the sand collecting drum is an important factor that affects the restriction structure,and further affects the performance of the separator,including separation efficiency and pressure drop.Due to the high pressure,it is difficult to directly measure the amount of sand in the sand drum.This article discusses the relationship between the amount of sand collected and the pressure drop of the separator,and provides an idea for on-site monitoring of the amount of sand.The main research contents and conclusions are as follows:(1)Based on the working nature of the cyclone separator,a model with a restricted structure was established,and the model was simplified,and the computational fluid dynamics software FLUENT was used for numerical simulation.By analyzing the cloud diagrams of different sand collection speeds,it can be known that during the initial sand settling,the center of the separator swings,but as the sand collection accumulates,the entire flow field becomes gradually stable.Through the CFD-Post post-processing software to analyze the particle movement trajectory,it is found that as the diameter of the solid particle increases,the possibility of its separation will increase.(2)Comparing the seven sets of test results,when the cyclone separator starts to work,as the sand storage increases,the separation efficiency begins to show an increasing trend.When the height of the sand collection is within 80%,the separator is in the optimal working range.Then as the amount of sand collected increases,the separation efficiency decreases.By analyzing the sand collection-pressure drop curve graph,with the gradual accumulation of sand at the bottom of the cyclone separator,the pressure drop tends to become larger as a whole.After the sand collection height accounted for more than 87.8%,the pressure drop increased significantly.(3)In the simulation of the impact of sand collection on the performance of the cyclone separator,it is found that the pressure drop has a significant non-linear relationship with the sand collection.Through MATLAB regression analysis,the pressure drop is proportional to the thirdorder polynomial of the sand collection.The study found that as the amount of sand collection increases,the pressure drop also increases rapidly,that is,when the cyclone separator is performing sand removal operations,as the amount of sand collection increases,the pressure drop of the separator increases.(4)Based on the above research,it can be seen that when the height of the sand collection is within 80%,the cyclone separator is in the optimal working range.Based on this,a sand monitoring idea is proposed,which is specifically as follows: Using this optimal working interval and combining with the actual size of the sand collecting bucket to determine the amount of sand to be collected during sand discharge,the value of this amount of sand is brought into the regression equation fitted in the text,and the set can be obtained.The pressure drop value under the sand volume.In actual work,by measuring the inlet and outlet pressure difference of the cyclone separator,when the pressure difference is close to the calculated pressure drop value,the operation is stopped and the sand is discharged in time.