基于AVL的发动机燃烧状态分析与故障诊断研究

Research on Combustion Analysis and Fault Diagnosis of Engine Based on AVL

发动机缸盖振动信号中蕴含着大量的能够反映缸内燃烧状态的信息,但由于发动机的工作过程复杂,缸盖振动信号分析难度大;而缸内压力虽然能够直观反映燃烧情况,但存在测量困难等问题。通过缸盖振动信号获取缸内燃烧情况的方法仍是研究的重点。本文旨在通过AVL仿真模拟和实验研究的方法探究发动机缸盖振动与缸内燃烧状态之间的关联,从而在没有条件获得缸内压力的情况下,利用缸盖振动信号特征变化实现在线监测诊断发动机燃烧状态分析与故障诊断。研究成果通过现场发动机燃烧故障的实际应用验证了本文方法的可行性和有效性。

Vibration signal measured on the engine cylinder head contains abundant information of combustion condition. However, due to the complexity of the engine operation, the vibration signal normally can be analyzed with difficulty; the in-cylinder pressure is difficult to obtain though it reflects the combustion condition directly. So the main emphasis of the research is still the acquisition of combustion condition by the vibration signal. The purpose of this paper is to study the relationship between the cylinder head vibration and the combustion condition by AVL simulation and experiment, in order to realize the on-line monitoring and the fault diagnosis of the engine combustion condition without in-cylinder pressure data, by means of analyzing the changes of characteristics of vibration signal measured on the engine cylinder head. The results of the research have been proved to be feasible and effective through the application of combustion fault in an actual engine.