Method for measuring effective internal sectional area of each hole of oil nozzle of diesel engine

Abstract

The invention discloses a method for measuring the effective actual internal area of each hole of an oil nozzle of a diesel engine, relating to the technical field of diesel engine injectors. On an injection pump test table, a force sensor with a certain area of thrust surface, which is arranged at a position apart from each orifice axis of an injector to be measured, is used for measuring spray momentum. According to the law of conservation of momentum, the measured force is equal to fuel momentum which is sprayed from each orifice; and meanwhile, the pressure of an oil nozzle pressure chamber and the needle lift are measured, thus calculating the changes of the effective actual internal area of each hole along with the changes of the time and the needle lift. The method can be used for preferably detecting the injector and controlling the quality so as to improve the performance of the diesel engine; and the method can be applied to detecting and controlling the quality of each hole of the injector in injector manufacturers and checking the quality of multi-hole injectors in diesel engine manufacturers.

Description

technical field [0001] The invention relates to the technical field of fuel injectors for diesel engines, and in particular proposes a method for measuring the effective flow cross-sectional area of ​​each hole of a multi-hole fuel injector. Background technique [0002] The fuel supply of diesel engines is generally to use the method of fuel injection to generate fine oil droplet groups, the purpose is to increase the evaporation and gasification area of ​​fuel and increase the heat release of combustion. This is a rather complex issue, and its complexity is mainly manifested in: [0003] 1) The fuel injection process is a dynamic process. The general speed of modern engines is 3000-6000rpm, up to tens of thousands of revolutions, the fuel injection time is quite short, and the fuel injection rules in a few milliseconds are also different, because the actual situation must be considered in the analysis of fuel injection; [0004] 2) Fuel spray is not only affected by the ...

AI Technical Summary

Problems solved by technology

[0005] 3) The oil droplets in the main part of the oil beam are very dense, and a liquid core will be formed from the outlet of the injector, and its length is affected by the structure of the injector. The current research on the relationship between the two is not deep enough

The effective flow cross-sectional area or flow coefficient of each hole of the orifice injector has an important influence on the fuel injection combustion and emission of the diesel engine, but it is difficult to measure, which makes it difficult for the injector manufacturer to detect and control the quality of the injector, and the diesel engine manufacturer The quality of the fuel injector can only be judged after the diesel engine is tested

[0009] In China, the method of measuring the flow rate of each hole of the orifice injector and the testing equipment used are still backward. Although there is a method of measuring the flow rate of each hole with a steady-state volumetric method, it is inconvenient to install and is affected by the diesel temperature and foam. The impact is relatively large, and it is not consistent with the actual working state of the fuel injector

Images