河海大学党委书记唐洪武教授做《平原河流水沙模拟测控技术与应用》学术报告

IAHR副主席、悉尼科技大学James Ball教授为唐洪武教授颁发证书

Abstract: China leads the world in the sizes and difficulties of designs and constructions of river-related projects, e.g., water conservancy structures, waterway structures and bridges. Due to the influence of complex river flow and sediment transport, the critical design parameters of large and medium-sized river-related projects shall be determined by physical models. Therefore, the results of these projects directly depend on the measurement and control accuracy of physical model tests. However, In the plains of eastern China with advanced economy, there are densely covered rivers which are connected to lakes and oceans. These rivers usually have a gentle hydraulic slope with to-and-fro water flow. There are also many river-related projects, e.g., locks, pump stations and bridges. These characteristics of plain rivers cause the great difficulties in the measurement and control of water and sediment parameters, including the requirements of (1) high measurement accuracy of flow and sediment parameters due to the large area of the prototype and the large scale of the physical model, (2) high control accuracy of the tidal boundary with a broad open boundary, and (3) standardization and integration of multi-parameters and multi-instruments. Technologies of measurement and control for physical models of plain rivers were developed to solve these bottleneck problems (i.e., high precision, high response speed, high integration). They consist of (1) measurement technologies for water level and flow velocity, i.e., an infrared water level meter which can eliminate errors of mechanical water level instruments caused by water surface tension and motion inertia of the probe (Figure 1), a synchronous measuring technique of the whole flow field, local flow field and point velocities (Figure 2), and a high frequency sampling method with the conventional particle image technology which can largely increase the sampling frequency; (2) measurement technologies for sediment and bed morphology, i.e., a method for separating fine sediment, measuring of angle of repose and settling speed, a laser sediment concentration meter which is suitable for measurement of a large variation range of sediment concentration, and an optical terrain measuring instrument which can identify the real bed surface affected by the high-concentration sediment layer near the bed; and (3) control technology of tidal discharge with a high accuracy which can accurately model the open boundary of the ocean area (Figure 3). Furthermore, a standard of data interaction between different measurement instruments was proposed, and then a multi-terminal system of flow and sediment measurement and control was developed (Figure 4). These technologies were applied to physical models for planning and designing optimization of many important river-related projects, e.g., regulation of branch channels in Nanjing reach of the Yangtze River and studies on proposal of construction of the Yongjiang Lock, and their key design parameters were scientifically determined.