Numerical Simulation And Structural Optimization Of New Horizontal Circumfluent Cyclone Dust Collector

A new horizontal circumfluent cyclone dust collector was proposed based on the study of cyclone dust collector to improve the separation efficiency,especially for the separation of small particles.The advantages of simple structure and wide application of cyclone dust collector were retained by the horizontal circumfluent cyclone dust collector.The issues of short circuit flow and secondary reentrainment were solved by changing the filter's structure.All aspects performance of the filter was improved.The study on horizontal circumfluent cyclone dust collector was carried out by means of structure design,numerical simulation and orthogonal test.The main work is as follows.The structure and size of the new filter were designed based on the idea of horizontal circumfluent cyclone dust collector.The initial geometric model was obtained.The flow field of the new filter was more stable and the turbulence of the flow field was greatly reduced.The filter model was simplified by reasonable assumptions.The numerical simulation of flow field in the horizontal circumfluent cyclone dust collector was carried out by reynolds stress model(RSM)provided by ANSYS Fluent.The distribution of velocity and pressure was analyzed under the condition of fixed inlet velocity with 22m/s.The results showed that the majority of total velocity was occupied by tangential velocity,which was beneficial to the separation efficiency;The axial velocity was small,but it played a significant role in the internal and external flow movement;The radial velocity was the smallest and local position had large value,With the help of guide tube,its influence to the flow field was reduced.The symmetry of the velocity and pressure distribution was well performed and the flow field was more stable because of the symmetry of the horizontal structure.The pressure was mainly static pressure,and the minimum was near the axis of the main cylinder and partial area was negative pressure.The pressure increased along the radius direction and reached the maximum near the cylinder wall.The main reason for the pressure drop was that the pressure greatly changed in the volute inlet pipe and the long and narrow exhaust pipe.The study on particle trajectory tracking used discretephase model(DPM)based on the study of gas flow field.The result showed that the separation efficiency of the filter to 1~5?m particles could reach more than 90%,which was greatly improved compared with the traditional cyclone dust collector.With the combination of orthogonal experimental and numerical simulation,research was conducted to test the influence on inlet size(A),ash outlet size(B),exhaust pipe diameter(C),spacing of dust separator tube(D),diameter of draft tube(E)and length of draft tube(F)with the fractional collection efficiency and pressure drop as the assessment criteria.The result showed that the optimized structure(A3B5C3D4E3F2)of the horizontal circumfluent cyclone dust collector obtained by integrated balance method can raise the fractional collection efficiency of 2?m particles to 97.01% with pressure drop only 1386 Pa,which could effectively deal with the separation problem of small particles.