J-type device needs to open the engine casing when using J-type cleaning device in the cleaning operation, which is shown in Fig.
By taking the scanning electron microscopy pictures of the water jet, he draws a conclusion that the fan nozzle was extremely sensitive to small variations in standoff distance.īy investigating and studying aero-engine cleaning status of Aircraft Maintenace & Engineering Corporation in Chengdu and Beijing, we learned they used J-type device and handheld device to do the aero-engine cleaning operation. They conducted some cleaning and erosion experiments to investigate the performance of them in jet coverage, which were based on the same input. Zhong and Han compared the performance of four water-jet nozzles, including standard cone-jet nozzle, fan-jet nozzle, a cavitating jet nozzle and a resonating jet nozzle. Arruda and Lawson observed the outflow of nozzle by injecting a steady flow. Then the water-jet characteristic of three fan nozzles was studied under different pressure, which was simulated with fluent. first established the geometric three-D model of fan nozzle and defined some main parameters of it. , who put up a design principle of nozzle to simulate the jet characteristic. The water-jet characteristic was influenced by the structure of different nozzles, which was drawn a conclusion by Chunyan et al. The size and velocity of droplet are the most important factors affecting engine cleaning process. Mund and Pilidi summarised the design parameters of online cleaning system, including droplet size and velocity, jet direction, temperature tolerance and cleaning frequency.
Now, online cleaning of aero-engine is the main way to slow down the engine performance declination, to extend the working time of aero-engine and to reduce the maintenance costs. This phenomenon causes the decline of aero-engine aerodynamic performance or the aero-engine surge, which will seriously lead to the aero-engine flameout in flight. Some of particles will gradually adhere to the surface or edge of gas path components to form deposition, which increases the wall boundary layer thickness and surface roughness of the gas path components in flow channel. The larger the incision angle and the nozzle area ratio are, the smaller the spray angle becomes.Īero-engine inhales air continuously during the working process, the particles suspended in the air will inevitably be inhaled into the engine. The jet shape is mainly determined by the nozzle area ratio and incision angle. Finally, the simulation results and orthogonal test results are verified by the injection experiment of the fan nozzle. The former two have more influence on the spray angle than the others. The results of the two analysis methods consistently show that the main order of influence of the geometric parameters of fan nozzle on spray angle is nozzle area ratio, nozzle incision angle, nozzle exit thickness, offset and nozzle convergence angle. The sensitivity of nozzle contraction angle, nozzle area ratio, nozzle incision angle, nozzle exit thickness and offset to the influence of fan nozzle spray angle was verified by range analysis and variance analysis. In order to determine the significance and importance order of the jet performance caused by fan nozzle's geometric parameters of aero-engine online cleaning equipment, the orthogonal experiment method, standard k –ɛ turbulence model and volume of fluid (VOF) two-phase flow algorithm are used to research the jet of fan nozzle. IET Generation, Transmission & Distribution.IET Electrical Systems in Transportation.IET Cyber-Physical Systems: Theory & Applications.IET Collaborative Intelligent Manufacturing.
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