Experimental study on microscopic and macroscopic characteristics of diesel spray with split injection
Experimental study on microscopic and macroscopic characteristics of diesel spray with split injection
复制标题
DOI：
10.1016/j.fuel.2016.01.083
复制
发表时间：
2016-06-15
期刊：
影响因子：
7.4
通讯作者：
Wyszynski, Miroslaw L.
中科院分区：
文献类型：
--
作者：
Wang, Ziman;Xu, Hongming;Wyszynski, Miroslaw L.
采用近场超高速成像技术、高速成像技术和相位多普勒粒子分析仪（PDPA）等技术，系统研究了柴油机分次喷射喷雾的微观和宏观特性。结果表明，单次喷射时，喷雾贯穿过程可分为四个阶段，这在很大程度上取决于喷射压力和环境压力。采用分次喷射策略时，第一次喷射的尾流速度高于外围气体速度所产生的“尾流驱动力”会使第二次分次喷射发生畸变，而第一次分次喷射产生的“空气驱动力”会使第二次羽流对称。此外，第二次喷射在初始阶段表现出较低的宏观穿透和喷雾面积，但在后期阶段表现出较高的宏观穿透和喷雾面积。此外，较高的注射压力导致更好的分散和更小的液滴。强烈的碰撞（包括主碰撞和二次碰撞）导致较大的液滴分裂注射比单次注射。较低的有效喷射压力，由于较低的喷射器开度的分流喷射策略被认为是部分负责较大的液滴尺寸。(c)2016爱思唯尔有限公司版权所有
The microscopic and macroscopic characteristics of diesel spray with split injection strategy were systematically investigated by employing ultra-high speed imaging in the near-field, high speed imaging and Phase Doppler Particle Analyzer (PDPA) techniques. It was found that for single injection there were four stages for the development of spray penetration, largely depending on injection pressure and ambient pressure. With split injection strategy, the "wake driving force" caused by higher speed of the wake of the first injection than that of periphery gas tended to distort the second split injection, whereas the 'air driving force' caused by the first split injection tended to make the second plume symmetric. Furthermore, the second split injection showed lower macroscopic penetration and spray area during the initial stage but higher macroscopic penetration and spray area at the later stage than the first injection. In addition, higher injection pressure lead to better dispersion and smaller droplets. The strong collision (both primary collision and secondary collision) caused larger droplets for split injection than for single injection. Lower effective injection pressure due to lower injector opening for split injection strategy was believed to be partly responsible for the larger droplet sizes. (c) 2016 Elsevier Ltd. All rights reserved.