Abstract: Unmanned underwater vehicle, which originated from ocean engineering, has been widely adopted in open water inspection of water conservancy projects, whilst it is seldom used in inspection of tunnel of hydropower station. Based on the analysis of system composition and current application cases, possible difficulties in hydraulic tunnel inspection via underwater vehicle are as below. First, multipath reflection of acoustic signal in the tunnel causes difficulties for application of underwater acoustic positioning and navigation technology. Second, clear images are difficult to be obtained by photoelectric imaging equipment because tunnel diameters of hydropower stations are often quite large. Third, if the tunnel axis is not straight, the cable would be obstructed by the friction at the turning, which leads to large resistance and even cable breakage. Forth, if the tunnel is long, magnitude of cable gravity and resistance will be very large. Possible solutions of the aforementioned difficulties are also analyzed.

Key words: unmanned underwater vehicle, tunnel of hydropower station, underwater inspection

摘要： 起源于海洋工程的无人水下航行器技术在水利水电工程开阔水域中已有较多的应用案例，但在水工隧洞检查中应用尚少。在对水下航行器系统组成、原理以及应用案例进行分析的基础上，提出水下航行器在水工隧洞检修中可能存在的困难包括：（1）声信号在隧洞内发生多途反射，导致水声技术的应用受到不同程度影响；（2）隧洞洞径大，光电成像设备较难获得洞壁的清晰图像；（3）隧洞轴线为非直线时，缆线在转弯处摩擦受阻，导致行进阻力过大，甚至可能发生缆线断裂；（4）隧洞较长时，采用ROV需克服较大的电缆重力和缆线阻力。文章对上述问题可能的解决途径进行了分析。

关键词: 无人水下航行器, 水电站隧洞, 水下检查