【作者】 袁泉；

【导师】 杨建国；

【作者基本信息】 武汉理工大学 ， 轮机工程， 2005， 硕士

【摘要】 船舶柴油机是船舶的动力心脏,其安全稳定的运行是保证航运安全的关键。通过对船舶柴油机进行在线状态监测和故障诊断,能及时发现设备存在的故障隐患、避免突发性故障停机和安全事故的发生。 实时监测系统是对机械设备运行状态进行评估和故障诊断的交互系统。在柴油机性能监测与分析系统中通过测量柴油机缸内气体压力信号、上止点信号和飞轮瞬时转速信号,计算得到柴油机指示参数作为性能评价的依据;在挖泥船液压设备状态监测系统中,通过测量关键点的油压变化信号,结合油液中颗粒污染物浓度分析评价当前设备的运行状态。状态监测与故障诊断系统采用三层结构,第一层为数据采集模块,第二层为状态监测模块,第三层为分析与预测模块。系统开发在虚拟仪器平台上进行,仪器的操作面板直观的显示监测数据及分析结果。软件系统具有集成度高、界面友好、操作方便和运行速度快等优点。 监测系统的数据存储通过后台数据库系统来完成,对数据库结构的设计是监测系统设计的重要组成部分。SOL Sever2000是Windows操作系统下的数据库开发平台,在其上设计数据表单和存储控制,使监测系统的后台存储模块得到了极大的简化。 通过示功通道测量柴油机缸内压力示功图是对其缸内燃烧过程进行分析评估的重要方法。对测量得到的示功图信号进行处理是其它数据处理的前提,文中阐述了在VC++软件开发环境中开发的示功图信号处理程序的程序结构和计算流程。 最后为了验证柴油机性能监测方法的正确性,进行了模拟故障试验研究。在4135型柴油机试验台架上测量柴油机缸内气体压力示功图和缸盖振动信号,模拟了排气门漏气和高压油管漏油故障下的柴油机工作状态。研究结果证明结合瞬时转速分析、气缸压力示功图分析、缸内燃烧放热率分析和振动分析能诊断出柴油机高压油管漏油和排气门漏气故障。更多还原

【Abstract】 The main marine diesel engines are usually the hearts of the ships, therefore, to ensure their running security and stability is the key to guarantee the manufacture. With on-line monitoring and diagnosing of marine diesel engines, the hidden fault can be discovered to avoid the stopping running of the power train and the occurrence of accident suddenly, and the prescient state maintenance before the fault taking place can be realized.On-line monitoring and diagnosing system is an intelligent system on monitoring condition and diagnosing fault. The system is composed by hardware parts, such as sensors, data acquisition card, and software parts. Dependability and validity are the standard to estimate a monitoring system. In the marine diesel engine performance monitoring system, three channels signals, which are air pressure in the diesel cylinder, the top dead center (TDC) and instantaneous speed of the diesel engine, were scanned, by which some important indicated parameters were worked out. In the dredger hydraulic monitoring system, the oil pressure of the important points on the hydraulic pipeline and the amount of the contamination particles were integrated to evaluate the state of the hydraulic system. Three levels frame are adopted in the monitoring and diagnosing system. The first level is the data acquisition module, the second level is the monitoring module, and the third level is the analyzing and predicting module. To establish the monitoring and fault diagnosis platform, virtual instrument is adopted. Measurement Studio for LabVIEW is used to realize the signal processing and analyzing, and the monitoring data and analyzing result are directly displayed by virtual instrument panel. The software system has high integration, friendly interface, easy operation and high running speed.The data storage of the monitoring system is carried out by background database (DB) system, so the design of the DB frame is an important part of a monitoring system. The SQL Sever2000 is an excellent DB developing platform, by which the storage table and storage control module were designed, and theprogram code were simplified.The indicator diagram of a diesel engine (I.C. engine) contains a lot of information as to the condition of the engine, and the combustion efficiency, which can be used to diagnose the combustion faults and other faults affecting the air pressure in the cylinder. The indicator diagram signal of the diesel engine are processed and analyzed by the gear averaging, wave filtering, and whole cycle averaging methods. The diagram frame and calculating flow, developing on the Visual C++ platform, were described.Finally, in order to verify the correctness of the monitoring methods, experiment the fault of exhaust valve leakage and high pressure fuel pipe leakage were simulated, had been carried out. The results indicate that the pressure indicator diagram and cylinder head vibration power spectrum can obviously reflect the fault information.更多还原