Experimental Study And Diagnosis Of The Typical Faults Of Diesel Engine Intake And Exhaust System

As one of the five major system of diesel engine, the intake and exhaust system is responsible for providing the sufficient air cleanly to each operating cylinders and discharging the last of the burned gases into the atmosphere, it’s the prerequisite for the normal operation of the diesel engine. Because of the job needs, diesel engine often works in the external environment of harsh conditions and poor air quality, all parts of the intake and exhaust system work over a long period of time at the internal environment with high temperature and high pressure. That often leads to intake and exhaust system faults. So, the fault diagnosis study of diesel engine intake and exhaust system has great significance.This research aims at three kinds of typical faults-the air filter clogging, the intercooler air side clogging, the exhaust pipe clogging, and establishes the online monitoring system for the typical faults of intake and exhaust system of diesel engine. then using an experimental methods of preset malfunctions, this research studies the different jam fault impact law to the influence of the diesel engine performance, and based on BP neural network technology to establish the online fault diagnosis system of the typical fault of the diesel engine intake and exhaust system. This article main research contents are as follows:1. This study established a fault simulation test bench for the typical fault of the diesel engine intake and exhaust system, it can simulate three kinds of fault-the air filter clogging, the intercooler air side clogging, the exhaust pipe clogging. And the system can online monitor seven kinds of performance parameters that are the compressor outlet temperature, the turbine outlet temperature, the compressor inlet pressure, the compressor outlet pressure, the turbine outlet pressure, the rotational speed and the load.2. The fault simulation test study: Under the various operating conditions, three kinds of law that the typical fault of the diesel engine intake and exhaust system impacts the compressor outlet temperature, the turbine outlet temperature and the rotational speed is the same. With the rotational speed and load increasing, the diesel engine is affected more seriously by clogging fault; the influence on the air filter clogging to diesel engine is little greater than that on the exhaust pipe clogging, and the influence on the intercooler air side clogging to diesel engine is obviously greater than the other two. 3. This study established an evaluation methodology of the typical fault of the diesel engine intake and exhaust system, this method can draw the safety range and maintenance range of the typical fault of the diesel engine intake and exhaust system pressure, and it provides technical support for the intake and exhaust fault diagnosis.4. This study based on BP neural network to establish a simple and efficient online diagnosis system for the typical fault of the diesel engine intake and exhaust system, the system can quickly and efficiently identify three kings of typical fault of the intake and exhaust system., so as to realize the diesel engine running condition monitoring and fault early warning.