Analysis Of Air Flow Around The Cylinder Of Comber And Study On The Structure Of Impurity Removal Channel

The structure of cylinder air duct of comber is complex.The high speed rotating cylinder and brush will produce the airflow boundary layer on its surface and affect the air flow in the machine,in addition,the influence of other components cause the air flow in the comber to be complex and variable.The air flow in the comber can not be effectively controlled,which will affect the cotton web quality.There are more hooked-fiber,bubbles,disorderly web,broken web phenomenon in the cotton web.With the increase of comber speed,the influence of air flow on the cotton web quality becomes more serious.Therefore,it is of great significance to study the air flow in cylinder air duct of comber to improve the cotton web quality and make the air flow in the comber adapt to the high speed.To solve the above problems,according to the structure of the cylinder air duct and the movement of the components in the comber,the air flow law is analyzed by stages with theoretical analysis method,The influence of 90°,110° and 130° cylinder combing arc surface on the air flow in cylinder air duct,web quality and combing noil were discussed.STAR-CCM+ is used to simulate the air flow in cylinder air duct,and analyze the air flow law and its influence on cotton web quality.STAR-CCM+ is used to simulate the air flow in cylinder air duct when the cylinder speed is 400,500,600 r/min and the cylinder combing arc surface is 90°,110° and 130° respectively,analyze the influence of cylinder speed and cylinder combing arc surface on the air flow in cylinder air duct and the cotton web quality.Design a new type of cylinder impurity removal channel,analyze the air flow law in the new type of cylinder air duct and its influence on the cotton web quality with theoretical analysis method.Simulate the air flow in the new type of cylinder air duct with STAR-CCM+ software,analyze the air flow law in the new type of cylinder air duct and its influence on the cotton web quality.The results show that:(1)in the brush cleaning stage,there is an upward air flow in the area between the cylinder,the front wall and the triangular air flow plate,and a vortex isformed under the detaching roller,which makes the end of the cotton web poured into the machine by the detaching roller floats upward,which has a bad impact on the lapping of the cotton web.(2)In the pre cylinder combing stage,the cotton web between the nipper and the detaching roller gradually thins until it breaks,and part of the air flow enters the cylinder air duct through the cotton web between the lower nipper and the later detaching roller,taking part of the short fiber and the spinning fiber away to form the noil.(3)With the increase of cylinder speed,the air velocity in the area between cylinder,front wall and triangular air flow plate increases,and the upward flow of air increases before detaching and lapping;and when the cylinder speed is 500,600 r/min,there is obvious vortex in this area,which has an increasing impact on cotton web lapping.(4)Compared with 90°cylinder(constant speed),the air flow in the 110° cylinder(constant speed)air duct has a greater impact on the cotton web quality,and the amount of fiber brought into the noil by air flow is less.Compared with the 110° cylinder(constant speed),the air flow in the 110°cylinder(variable speed)air duct has less influence on the cotton web quality,and the amount of fiber brought into the noil by air flow is less.Compared with the 110° cylinder(variable speed),the air flow in the 130° cylinder(variable speed)air duct has a greater impact on the cotton web quality,and the amount of fiber brought into the noil by the air flow is less.(5)The new structure of cylinder impurity removal channel can improve the adverse effect of air flow in the original cylinder air duct on the cotton web quality through the air flow channel formed between the brush air hood and the front wall,so that the air flow in the comber can adapt to high-speed and high-quality production.