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1.前言在柴油机等内燃机中,处于飞动状态的燃油喷雾粒径的大小和分布情况,都直接影响着燃油的燃烧效率和排气成分。但是,液体燃料的喷雾是由许多微小的粒子群组成,并容易蒸发及结合,所以要把这些微小的粒子收集起来且正确地做出测量,是非常困难而又费力的。在以前采用的测量液体燃料喷雾的粒子直径分布的方法中有撞击法(液浸法)、沈降塔法等,虽然它们各有其优点,但是都很难做到将飞动状态下的喷雾的粒子直径分布瞬时、直接地测量到数微米级的粒子直径。此外,还有用高速照像机来拍照飞动状态的方法等,可是用这样的方法要对每个微小的粒子的大小做出正确连续地测量,也是非常困难的。
1. Introduction In internal combustion engines such as diesel engines, the size and distribution of fuel spray particles in the flying state directly affect the combustion efficiency and exhaust composition of the fuel. However, the spray of liquid fuel is composed of many minute particle groups and is easy to evaporate and combine, so it is very difficult and laborious to collect these tiny particles and measure them correctly. Among the methods used to measure the particle diameter distribution of the liquid fuel spray, there are the impact method (liquid immersion method) and the settling tower method. Although each has its own advantages, it is very difficult to achieve the effect of spraying Particle diameter distribution Instantaneous, measured directly to the particle diameter of several microns. In addition, there is a high-speed camera to take a picture of flying state, etc., but in such a way to measure the size of each tiny particle correctly and continuously, it is very difficult.