文档介绍:南京航空航天大学
硕士学位论文
柴油机高压共轨电控燃油喷射系统数值模拟计算
姓名:蔡珍辉
申请学位级别:硕士
专业:车辆工程
指导教师:杨海青
20080101
南京航空航天大学硕士学位论文
摘要
随着全世界环保意识的逐年加强,能否满足日益严格的排放法规和日益提高的
用户使用要求,决定了内燃机生产厂家的兴衰成败。因此拥有低油耗、低价格、低
排放、低噪声和高性能的新型内燃机是各厂家追求的目标。被誉为二十世纪内燃机
关键技术三大突破之一的柴油机高压共轨系统成为了研究的热点,它在改进柴油机
并优化其性能的过程中,起着决定性作用。在当前所有的燃油喷射系统中,柴油机
高压共轨系统能有效地降低发动机油耗、排放并提高发动机动力性。该系统具有喷
油压力独立控制、喷油定时灵活控制和喷油量可灵活控制的特点。
本文介绍了高压共轨系统的特点及国内外发展现状,并详细介绍了高压共轨系
统的构成及基本原理。利用仿真计算和试验验证的方法,研究了高压共轨系统的喷
射特性和共轨内压力波动的影响因素。首先建立了高压油泵、共轨和喷油器的数学
模型,利用模块化分析方法,最终建立了数值模拟模型;然后在油泵试验台上对高
压共轨系统进行一系列试验,所得到的试验结果与计算结果进行对比可知,两者总
体变化趋势比较吻合,说明本数值模拟模型能够达到仿真的目的和要求。
最后,通过独立地改变喷油始点、电磁阀开启脉宽、喷油器结构参数进行仿真
计算,得到了各参数对系统喷射特性和共轨内压力波动的影响情况,为系统设计和
改进提供了依据。
关键词:仿真计算,电控,高压共轨,柴油机
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柴油机高压共轨电控燃油喷射系统数值模拟计算
ABSTRACT
With the future emission legislation challenging goals will be defined for Diesel
engine manufactures. Lowest emissions with highest engine performance, low noise level,
low fuel consumption and attractive costs are defining the targets of their development
activities for future engine. A fuel injection system assists this development and es
the decisive factor to reach targets. The electronic-controlled high-mon rail
diesel injection system is more effective in emission reduction and engine performance
improvement among all of the fuel injection system currently. This new system has the
features of adjustable injection pressure, injection quantity and injection rate.
This paper introduces the advantages of the high-mon rail fuel injection
system, the domestic and foreign researches; and ponents of system and how they
work in detail. With the simulating calculation and experiment, the detail analysis has
been done on injection characteristic and dynamic pressure characteristic inside rail. First,
the numerical models of high-pressure pump, rail and injector is founded, using the
calculating method of model unit, the simulating model is developed. By experimented on
the mon rail