用激光衍射法研究柴油机高压喷雾(Ⅰ)——常温常压下粒度分布特性

An Investigation on Diesel Spray at High Injection Pressure Using Laser Diffraction Method(Part Ⅰ)——Under of Ordinary Ambient Temperature and Pressure

本研究在一特制的容弹中,采用经改装的寇明斯PT 喷油系统实现了高压喷雾,喷油压力达130MPa 以上。和曾见报导的用升压器等方法获得的高压喷雾相比,这种喷雾更接近实际柴油机中的喷雾;和用增大普通油泵柱塞直径等方法获得的高压喷雾相比,这种喷雾的喷油压力要大得多。应用Malvern 2604C 型粒子分析仪对高压喷雾的粒度分布及各种影响因素进行了一系列研究。本文是这一系列研究的第一部份,着重报导在常温常压下测定的喷雾粒度随空间和时间的变化规律,因为这是进一步对其他影响因素进行比较研究的基础。结果表明高压喷雾的质量要比常规喷雾有很大的改善。同时,还揭示出在静止介质中喷雾结构的一些细节。

To investigate the diesel fuel spray behavior at injection pressuresas high as 130 MPa,a series of experimental studies were carried outin a combustion bomb with a reconstructed Cummins PT fuel systemwherein the droplet sizes were measured by the MALVERN 2604C particlesizer based on the principle of laser diffraction.The results obtained atordinary evironment temperature and pressure show that the droplet sizesin the pulsed spray vary with their position within the spray and withthe time delay related to the start of injection.It is found that thequality of atomization of fuel spray injected at high pressures wasgreatly improved.