Detection System Of Spray Shape For Gasoline Engine Injector Based On Machine Vision

As the core component of the automobile engine,the quality of the fuel injector has a direct effect on the efficiency of the engine and the fuel economy.The spray shape of the fuel injector is an important factor affecting the performance of the engine.Therefore,it is of great significance to study the detection technology and evaluation method of spray shape of fuel injector in gasoline engine.According to SAE J2715-2007 promulgated by Society of Automotive Engineers and QC / T 967-2014 enacted by National Technical Committee of Auto Standardization,this paper designs detection system for spray shape of gasoline engine injector based on machine vision technology,including constant temperature and pressure control system,fuel injection control system,high-speed photogrammetric visual inspection system and H-R(High-Resolution)handling and analysis system.The detection system has studied the test method of spray shape of gasoline engine injector.The main tasks include:(1)The design and development of detection system for spray shape of gasoline engine injector based on machine vision,The system mainly includes fuel control module,spray transient image acquisition module and image processing analysis module,which are integrated with GDI(Gasoline-Direct Injection)and PFI(Port Fuel Injection)injector.(2)The high speed photography method is used to study the spray shape of GDI injector.The Phantom series high-speed camera from Vision Research Company detects SOF(Start of Fuel)and obtains spray images at the standard delay time.Combined with the image processing algorithm,the spray shape parameters such as spray angle,spray bend angle and spray tip penetration are calculated and analyzed.(3)According to the standard requirements,this article has designed the H-R processing analysis system for the detection of PFI injector.Firstly,the mass distribution of fuel was collected by collection vessel,the fuel quality of collecting vessel unit was collected by H-R system one by one,and the mass distribution of fuel spray in the small holes of each collecting unit was analyzed.This article gives a detailed detection method and algorithm implementation.(4)The stability of the system is verified by the complete spray shape detection based on the existing six-hole GDI injector and the four-hole dual-stream PFI injector.At the same time,the influence of on start of fuel,spray angle,spray tip penetration and so on under different pressures of GDI injector was also analyzed.The spray shape characteristics of the GDI injector and PFI injector were compared,the results show that the injection pressure of the GDI injector is high,the atomization effect is good,and the oil bundle is relatively loose.It has broad prospects in the future.