中文摘要：

从6DK20型船用中速柴油机结构特点出发，研制了热电传感器，测取了典型磨损状态下各负荷工况下的热点信号，分析了热电信号的指向性，比较了主轴承不同磨损量、不同负荷情况下，柴油机发火时刻对应的热电信号峰值变化情况。结果表明：热电信号真实地反映了主轴承的磨损及运行状况，具有良好的故障指向性及瞬变性；应用热电技术在线监测主轴承磨损具有很好的工程实用性。

英文摘要：

Based on the structural characteristics of 6DK20 type medium-speed marine diesel engines, a thermoelectric sensor was developed, the thermoelectric signals under typical wear states with varied load conditions were measured, and the thermoelectric signals＂ directivity was analyzed. Moreover, the different signal peaks corresponding to diesel ignition timing under different wear level of main bearing and different load conditions were compared. The results prove that the thermoelectric signal is a true reflec- tion of the state of the main bearing wear and running condition, boasts good fault directivity and transient nature. The application of thermoelectric technology in online monitoring of main journal bearing wear has good engineering practicability.