Research On Joint Energy Dissipation Of Ski-Jump With Hydraulic Jump

"Big discharge,tall water head and narrow canyon" have been the characteristics of water power exploitture,which denotes the difficulty of water power exploitture is increaseing,also brings challenging problem to research of flood discharge and energy dissipation.Based on analysis of traditional energy dissipator and making use of their virtues, this paper advances a new type energy dissipator named joint energy dissipation of ski-jump with hydraulic jump.The following contents are researched:(1) Based on analysis of traditional energy dissipator and summarizing their advantages and disadvantages,joint energy dissipation of ski-jump whir hydraulic jump is advanced creatively;(2) The difference between this new type energy dissipator and joint energy dissipation of flaring gate pier with others are strictly differentiated,three manners of rising and their applicable confine are put forward at the same time;(3) Based on momentum equation,hydraulic calculation formula of joint energy dissipation of ski-jump with hydraulic jump are educed and indispensable condition M_max =0.3849＞M is given,the effect of h₁ to the result is calculated,which is very small and can be ignored;(4) Based on enduced formula and given conditions,the relationship of q,αandΔh is computed and listed in tables,from which it can be seen water deep after hydraulic jump is receded and longth of stilling basin is shorten largely,so the cost of project can be saved excessively;(5) Discharge capacity of spillway,pressure along the line and water depth are measured,which indicate the request of flood release is met,pressures are all positive,water surface wave is small and flow pattern is rather better.The positions where cavitation and cavitation erosion occur easily are researched,the result indicates the possibility of occuring cavitation erosion is very low;(6) The result of experiment on energy dissipation indicates that the effects of joint energy dissipation rised by flaring gate pier is very excellent,which agree with compution result perfectly,the flow patern is rather better in stilling basin and depth of scouring is receded badly;(7) Through model experiment,relation of reservoir water level and discharge of spillway tunnel is gotten,pressure along the line and water depth are measured,the result of which meet request and water surface wave is small.Joint energy dissipation of ski-jump with hydraulic jump rised by part side shrinkage adding small jet bucket is applied to energy dissipation of spillway tunnel,experiment result indicates this type of energy dissipation runs well and energy is dissipated fully.