缸盖热状态的正常与否是保证发动机可靠工作的重要因素之一。本文以某型柴油机缸盖为研究对象，确定了高、中、低3种试验工况，采用红外测温技术，检测了实机工作状态下缸盖外表层测点温度随发动机工况的变化规律。提出相对灵敏度的概念，并结合数值仿真，确定了发动机缸盖表层温度特征区域。试验和仿真结果表明，在缸盖结构以及发动机工况一定时，缸盖的所有传热边界条件也保持一定，缸盖表层温度可综合反映其整体温度场，可作为评价其热状态的依据。该研究为实现发动机缸盖热状态的在线监测提供了新的途径，同时也拓展了红外检测技术的应用领域。

Whether thermal condition of cylinder head is normal or not is one of important factors to evaluate Engine’s reliability performance. Based on infrared temperature measurement technology, the correlative rule of outer surface temperature field of cylinder head with working condition of engine was studied on one certain diesel engine. Combined with simulation calculation, characteristic temperature field distribution was developed on outer surface of cylinder head. The results showed, simulation values were well matched with experimental values. Under same structure and heat transfer condition of cylinder head, the thermal condition performance of engine can be described by outer surface temperature values, which provides a new gist for monitoring thermal condition of cylinder head on-line. Furthermore, applied infrared temperature measurement to engine has a widely foreground.