中文摘要：

针对水利工程试验中水下模型地形的测量问题,分析比较了高频超声回波信号与阵列超声成像信号特征,并提出了一种超声成像测量方法。该方法直接利用高频超声成像仪获取水下模型地形的实时图像,通过分析提取图像中的地形成像亮带线,从而实现水下模型地形的快速无接触实时测量。结果表明基于高频超声成像的测量方法能够有效地规避水中悬浮粒子对水下模型地形测量的干扰,能够实现地形的实时测量,测量误差在3个像素宽（1.8 mm）以内。该方法自适应性强,速度快,分辨率高,为水下模型地形的动态分析与实时测量提供了一种有效途径,并已运用到实际工程中。

英文摘要：

As for the measurement problem of the underwater model terrain in physical model tests of hydraulic engineering, the authors analyze the characteristics of high frequency ultrasonic echoes and array ultrasound imaging signals and propose an ultrasonic imaging terrain survey approach. This approach is by using a high- frequency ultrasonic imaging device to obtain the real-time image of the underwater model terrain. A fast noncontact and real-time survey of the underwater model terrain is realized by analyzing the ultrasonic imaging signals and extracting the imaging terrain lines. The results show that the approach can effectively avoid the interference of suspended particles to model terrain survey under water flow and realize the real-time measurement for the underwater physical model terrain. The measuring error is within 3 pixels wide （about 1.8 mm） with the advantages of strong adaptability, fast speed and high resolution. This approach can provide an effective method for the dynamic analysis and real-time survey of underwater model terrain. It has been used in practical engineering.