Propagation and Development of Nonlinear Long Waves in a Water Saving Basin

Abstract

The water saving lock layout plays a key role in addressing the navigation hydraulic problems with high dams. However, the study of the propagation and development of nonlinear long waves induced by ship-lock operation in a water saving basin has received less attention so far. Specially, the mechanisms governing the formation of secondary waves and the impact of these waves on the impoundments of the basin are still not fully understood. In the present study the entire evolution of a nonlinear long wave in a water saving basin was numerically simulated. The wave shape, wave celerity and wave force were analyzed. It was found that the leading edge of a long wave propagated along the water saving basin with a celerity which varied with time and space. Two distinct stages could be recognized and defined: a rapid acceleration phase characterized by a sharp increase in the celerity with propagation distance and a gentle acceleration phase where the long wave propagated in a more gradual manner. Moreover, the water surface slop of a long wave front equal to 0.045 could be used as an estimate of the occurrence of secondary waves. Furthermore, the present results highlighted the wave force on the impoundments of a water saving basin was controlled by wave nonlinearity. These results may provide theoretical guidance and technical support for the hydraulic design and operation of water saving locks.