Experimental Research On Monitoring And Diagnosis Technology Of Cylinder-piston Ring For High Speed Diesel Engine

As high-speed diesel engines are widely used as power plants in engineering machines, generators and trucks, the high requirements of the safety and reliability should be satisfied. Due to the complicated structure and the various serious working conditions, and the long-term continuous operating of a high-speed diesel engine, it is easy to cause a economic loss and to put staffs safety in danger once fault occurs. With the fast development of the computer science and the information technology, the development of the diesel engines put forward to the automation and integration, the monitoring and diagnosis methods is improving better. Timely potential failure information of the diesel engine is monitored and the measures are taken, the safety and reliability of the diesel engine is improved and economy is assured. In the thesis, WP10-240 diesel engine selected as the research object, the experimental research on monitoring and diagnosis technology of cylinder-piston ring for a high speed diesel engine was carried out, the main contents and results follows:1.The method of monitoring and diagnosis for a diesel engine was presented in the paper, the priciple of diagnosing cylinder-piston ring faults was analyzed, the theoretical basis was offered for guiding the faults simulated test of the a cylinder-piston for the high-speed diesel engine.2.Three typical faults were simulated on WP 10-240 type diesel engine, which included a misfire on single cylinder, wearing of the liner and piston ring wear. The cylinder pressure signals, Top Dead Centers (TDC) signals, and speed signals and the cylinder block surface vibration signals of the diesel engine were measured and analyzed; the feature parameters were abstracted, the interactive relationship between the feature parameters and the faults was established.3.The cylinder pressure signals were processed by the diesel engine equal-crank angle, the multi-period average and the smooth handling methods, the surface vibration signals on the engine block on combustion section were selected and analyzed. The feature parameters were abstracted, and the fault diangosis critera were obtained by comparing with of the feature parameters.4.The instantaneous angular speed signals of the diesel engine were processed by the period average, tooth average and smooth handling methods, the instantaneous angular speed signals of a single cylinder misfire, the wearings of the cylinder and piston ring were analyzed. The fault diangnosis critera of the instantaneous speeds for misfire were obtained. The possibility of diagnosing other faults by using instantaneous angular speed was investigated.