DISCHARGE RATES OF DIFFERENT PARTICLE SIZE GROUPS DURING RESERVOIR OPERATION OF THE YELLOW RIVER

摘要

Size-group discharge calculation in reservoirs on sediment laden river (hereinafter referred to reservoir size-group calculation) is an important part of scouring and silting calculation in hydrological models.The calculation results of reservoir sedimentation are closely related to the reservoir operation mode. The establishment of a correct size-group discharge relationship and accurate calculation of deposition in reservoir and outflowing sediment grading are important to both the reservoir operation scheme and fluvial process calculation for the downstream river channel. On the basis of past studies, by means of empirical analyses of over forty-year observed data of Sanmenxia Reservoir, the reservoir size-group discharge relationship is established. The data of different periods of Sanmenxia, particularly hyper concentrated flows and initial operation of Xiaolangdi Reservoir show that such relationship is practical to calculation of size-group discharge for reservoir sediment mathematic model research and sediment discharge design for silt-laden reservoirs. The results have been adopted by the operation mode research of Xiaolangdi and Guxian reservoirs on the Yellow River, the study topic 98-928-02 (already approved by the state authority) of the national "Ninth-five Year Plan" and included in sediment volume of Manual of Hydraulic Energy Design.