The Research Of Gasoline Engine Fuel Injector Spray Characteristics Detection Method

Fuel injector is the core component of gasoline engine,which quality directly influences the working efficiency and comprehensive performance of the gasoline engine.Spray characteristics of injector is an important factor to affect combustion quality of gasoline,its spray mist shape and degree of atomization both have key influence on the combustion efficiency of gasoline.So the spray characteristics of gasoline engine fuel injector on comprehensive test research is of great significance.According to SAE J 2715 issued by the American society of automotive engineers and GB/T 25363-2010 standard published by China machinery industry federation,this paper designs and builds a set of spray characteristics test experiment platform of the gasoline engine,including fuel injection system,visual monitoring system,the spray characteristics of measure and other auxiliary equipment in order to study GDI and PFI injector characteristics.Main work includes:1)Design and build the inlet type spray form distribution test system hardware platform,gives the detailed test process and data processing algorithm implementation;2)High-Speed imaging technology is used to study GDI spray macroscopic characteristics.Phantom series High-Speed cameras of company Vision Research's is chosen to capture the transient spray image at a given moment,combined with image processing algorithms,calculate the size of the spray angle and the penetration in this image.3)Study the microscopic characteristics of both injector.Use a laser spectrometer collect the light energy distribution of different droplets size,and then obtain the particle size distribution directly by computer.4)Conduct a complete test of PFI and GDI injector.The experimental results show that spray along PFI injector axis was dispersed into two beams,which quality concentrated on the right.The degree of separation does not exceed 10 °.Comparatively,GDI spray was single with 0.06 ms delay time.The spray fully develop at 1.5ms after injector starts working,at Which time the spray angle and penetration distance is 51.4 °,74.4 mm.PFI spray particle size range is about 90?m,far greater than GDI spray,the latter is only 35?m.