Study On The Abrasive Flow Polishing Process Of The Center Flow Channel Of The Auxiliary Of The Engine Fuel Nozzle

With the development of aviation machinery products in the direction of high precision,miniaturization,and density,the surface quality requirements of products are getting higher and higher.The micro-holes of the auxiliary nozzle of the aero-engine fuel nozzle are high-precision micro-holes,which require a very high surface quality.The traditional manual polishing process cannot meet its accuracy requirements,and it cannot guarantee the consistency of polishing.The working efficiency of the tiny holes in the auxiliary nozzle of the fuel injection nozzle is very low.In recent years,the automatic abrasive flow polishing process,which has been popular all over the world,uses viscoelastic abrasive to flow through the inner surface of the micro-hole of the auxiliary nozzle of the aero engine nozzle to be processed under the pressure of the abrasive flow machine tool,which can effectively remove the spray.The burr inside the center flow channel of the auxiliary nozzle of the oil nozzle ensures the consistency and uniformity of polishing,which greatly improves the operation efficiency of the inner surface of the center flow channel of the auxiliary nozzle of the engine nozzle.In this paper,the auxiliary nozzle of a certain type of aeroengine nozzle is taken as the research object,and the abrasive particle flow polishing is carried out on the central flow channel of the auxiliary nozzle of the nozzle.The following is the main research content:For the auxiliary nozzle of the fuel injection nozzle provided by the cooperative enterprise,a special abrasive flow processing fixture is designed to be used for the abrasive particle processing test of the auxiliary nozzle of the injection nozzle.According to the actual structure of the secondary nozzle of the fuel injector of the engine,the Gambit software is used to model the two-dimensional model of the central flow channel area of the secondary nozzle of the fuel injector.After the built two-dimensional model is segmented,the line and surface meshes are divided in Gambit software,and the boundary conditions such as the entrance and exit of the model are set.Finally,it is imported into Fluent software,combined with the relevant theory of computational fluid dynamics,the flow process of abrasive in the center flow channel of the auxiliary nozzle of the fuel injector is simulated,and the dynamic pressure,Velocity and turbulent energy distribution clouds.Through the obtained simulation data,the effects of different processing parameters such as abrasive grain size,abrasive volume fraction,and extrusion pressure on the center flow channel of the auxiliary nozzle of the abrasive flow polishing nozzle are analyzed.The process test of the center flow channel of the auxiliary nozzle of the abrasive flow polishing nozzle was carried out,and then the inner surface roughness of the processed workpieces under the four process parameters of abrasive particle size,abrasive volume fraction,extrusion pressure and processing time In the test,the roughness value is used as the standard for evaluating the polishing effect,and the roughness of the inner surface of the workpiece under the test of each group of process parameters is compared.The results show that the effects of abrasive particle size,abrasive volume fraction,extrusion pressure and processing time on the polished workpiece from large to small are in order of abrasive volume fraction,extrusion pressure,processing time and abrasive particle size.The best abrasive particle flow processing parameters are: abrasive volume fraction is 20%,extrusion pressure is 6.5MPa,processing time is 30 s,abrasive particle size is 48 um.The research shows that the process of removing the burr at the center flow channel of the auxiliary nozzle of the fuel injection nozzle by the abrasive particle flow is feasible.