Numerical Simulation And Structure Optimization Of The Venturi Powder Ejector

Powder spray technology as a kind of surface treatment technology is increasingly used in industrial production.The coating has the advantages of less pore, better anti-corrosion performance, thicker film coating, and etc. Because of low efficiency of the powder ejector, the inner flow field in the venturi powder ejector and the gas-solid two phase flow coupled of powder particles are numerically simulated. Meanwhile, the author analyzes the flow field and finds out the characteristics of gas-solid coupled flow in the powder ejector.According to these results, the author uses a method of function of gas dynamics to design a new powder ejector to improve the efficiency of the particle conveying.First of all,this paper studies the development of the venturi powder ejector and gives a simulation method of venturi powder ejector based on computational fluid dynamics theory. Then,the numerical simulation needs ICEM software to repair the geometry model and generate unstructure mesh to finish the preprocessing task.Based on the preprocessing, standard two equation turbulence model,the density of explicit solver is selected as a steady numerical simulation analysis of the venturi powder ejector.In addition,observe the powder ejector flow field,it acquires the information about velocity vector, static pressure, temperature. At last, adopt the euler-Lagrange model to simulate the venturi powder ejector, it can give us the particles trajectories.Based on the method above, two kinds of commonly used powder ejector are simulated and an experiment is designed to test the powder ejector’s work efficiency.The test result shows that the numerical simulation method is adapt to the study of venturi powder ejector’s work efficiency.Aiming at the problems of powder ejector, this paper designs a new powder ejector through the function of gas dynamics.It has a more reasonable geometry. The simulation indicates that the new design solves the problem of flow field, such as eddy, particle flow hampered. Furthermore,changing the parameters of the structure and researching the powder ejector performance, this paper gains the relationship between the structure parameters and performance, which is beneficial to improve the work efficiency of powder ejector.Currently, the study of venturi powder ejector is still in the stage of experiment. It wastes a lot of resources. Therefore, this paper adopts numerical simulation,experimental validation and optimization design, which greatly reduces the period of product development cycle, providing a reference for the powder spray technology. The method used in the paper is also suitable for other ejectors.