油膜厚度测量是流体润滑理论研究的重要内容及难点之一，是大型高速设备状态监测的关键，但这一问题却因测量方法和技术的限制一直没有得到很好解决。利用超声波的穿透和反射特性对油膜厚度进行直接测量是一种新方法。前期研究发现，传感器中心工作频率和测量精度有着密切的联系，传统的陶瓷块体换能器因其中心频率低而难以实现薄油膜的测量。为此提出一种相控阵AlN压电陶瓷薄膜油膜形状测量方法，应用AlN压电陶瓷薄膜厚度中心频率超高的优势提高测量精度，结合相控阵原理提高对测量区域的分辨率。因此需要弄清相控阵陶瓷膜超声传感器的工作机理，建立相控阵油膜形状测量模型，研究传感器设计及应用中存在的关键问题，实现油膜形状的可视化。项目的研究可为油膜形状测量开辟一条新途径，为润滑理论研究提供一种强有力手段，为关键设备状态监测提供新的方法。

Measurement of lubricant film thickness and shapes is an important and difficult research areas of machine lubrication and wear,it is a key problem of large and high speed equipments condition monitoring,but this problem has never been satisfactorily resolved because of the limitations of the measuring method and techniques on line, even if in the laboratory, this problems did not get a satisfactory solution too. It is a new methods to measure the oil film thickness by the use of penetrating and reflecting characteristics of ultrasonic waves. Previous study found that the higher centre operating frequency of the sensor could signifcantly imporve the measurement accuracy,it was difficult for the traditonal piezoelectric block transducers to be used to detect the thinner oil film thickness because of their low centre freqencies. So a new ultrasonic phased array pizoelectric AlN film oil film shape measurment method is proposed,its high centre frequency could improve accuracy and the phased array methods could be used to increase resolution of measurement filed.So it is necessary to study the mearsuring mechansims of the phased array ultrasonic ceramic film oil film sensor, build the measuring model for phased arrary methods, study the key problems on the design and use of the new kind oil film sensor, completed the visualization of oil film. With the studing of this project,a new researching way of lubricant film shape is open up. These new technologies could provide a powerful means and measures for the study of lubrication theory and new method for equipment real-time condition monitor too.