Optimized Design Of Airflow Channel For Foreign Fiber Sorter

As foreign fibers in cotton reduce the quality of products,cotton spinning companies currently use foreign fiber sorters to detect and reject foreign fibers.However,the unreasonable structure of the foreign fiber sorter leads to a decrease in the rejection rate of foreign fibers.In this paper,the problem of large amount of cotton falling and serious energy loss in the process of removing foreign fibers from the nozzle of foreign fiber sorter is analyzed.In addition,the problems of uneven distribution of cotton flow velocity and unreasonable distribution of cotton flow caused by unreasonable structure of cotton conveying channel are studied.The key is to optimize the design of the nozzle tube structure and the cotton channel structure.By analyzing the relationship between airflow velocity and wall section,based on the principle of supersonic speed of Laval nozzle,the plate on the nozzle is designed as a profiled Laval nozzle with a rectangular cross section.Then,combined with the numerical simulation method,the flow field changes in the nozzle plate are analyzed.For the problem of profile transformation of the profiled section Laval nozzle,the section conversion is performed by the equal length and other cross-sectional area conversion method.The initial position of the profile conversion and the width to length ratio of the nozzle outlet are determined by numerical simulation.It is verified that the quality of the nozzle flow field before and after the deformation has not changed due to the change of the profile,which ensures the quality of the nozzle flow field.By analyzing the influence of structural changes of the cotton channel on energy loss,based on the theoretical calculation method of energy loss,the angle of the cotton inlet of the cotton channel,the radius of curvature of the pipe,and the angle of the pipe are optimized.And design a diffuser between the cotton inlet and the vertical bend.Combined with the numerical simulation method,the variation of airflow velocity and the variation of cotton flow distribution in the cotton conveying channel are analyzed.The accuracy of numerical and theoretical calculations is determined by numerical simulation.The optimized nozzle outlet axis velocity is analyzed by the experiment of the speed measurement test bench,and the numerical simulation results and the accuracy of the experimental results are analyzed.The optimized nozzle plate is verified to make each outlet speed uniform and achieve optimal rejection speed,reduce inlet pressure,and reduce energy loss.In this paper,the theoretical calculation,numerical simulation and experimental verification method are used to optimize the structure of the nozzle plate and the cotton conveying channel of the foreign fiber sorting machine.Through theoretical calculation,numerical simulation and experimental verification method,this paper optimizes the structure of the nozzle plate structure and the cotton conveying channel structure of the foreign fiber sorter,and solves the problems existing in the original nozzle plate and the cotton conveying channel.So the optimization scheme is feasible.