Energy Dissipation Characteristics Of Multiple Three Dimensional Wall Jets For Shiplock Filling And Emptying System

Shiplock is one of the main types of inland navigation structures and it occupies a pivotal position in the water transportation of our country.The water system that controls the frequent operation of locks is the heart of a shiplock and Its design level directly affects the operation efficiency and reliability of the shiplock.The lock wall promenade road and the multi-branch water supply system are one of the main types of distributed water conveyance system.It has many advantages,such as simple structure,low cost and good flow condition,so it is widely used in actual shiplock engineering.The type of water conveyance system involves the jet structure not only has the general characteristics of multiple turbulent jets,but also the special case of multiple three-dimensional wall jets,and its flow characteristics are affected by more complicated boundary conditions.The energy dissipation mechanism is more complex,and has attracted much attention of scholars.In order to clarify the flow characteristics and energy dissipation characteristics of the three-dimensional wall jet and the key control factors that affect the energy dissipation effect of the sidewall and multi-branch water supply system,this paper uses the RNG ?-? turbulence model and SIMPLEC algorithm in fluent numerical simulation software to simulate the energy dissipation characteristics of multiple three-dimensional wall jets.The main research contents and research results as follows:1.A constant multiple three-dimensional wall jet model has been designed according to the scale of 1:50.36 calculation conditions combinated with different number of branch holes,branch hole spacing,the momentum flux ratio and radial distance are calculated.The energy dissipation characteristics,energy dissipation mechanism and energy dissipation effect of the three-dimensional multiple wall jet in the filling and emptying system of shiplock are mainly studied.2.There are mainly three ways of elimination of filling and emptying system of three-dimensional multiple wall jet: the first one is the formation of a kidney shaped vortex on formed by around the reverse shearing action;the second is consumed by the collision of the jet with the opposite wall of the branch hole;the third is throughing the mixing of two jets in the gate,a strong turbulent flow is formed to dissipate energy.3.Exhibition of shiplock filling and emptying system of three dimensional multiple wall jet to speed wide half value increases with the increase of radial distance,and the maximum increases with the increase of radial distance.Prior to entering the convergence zone,the expansion of the parallel double hole is basically the same as the single-stranded jet stream.However,after entering the convergence zone,the space of the perforation determines the location of the virtual source and the width of the expansion.The momentum flux ratio is affected the exhibition to speed wide in the region of 10(27)y(7)A^ 0.5(8)? 22.7,and the momentum flux ratio is larger while the exhibition to speed wide is smaller.4.In actual engineering,when the distance between the two perforations is same,the larger the radial distance,the better the energy dissipation effect of the three-dimensional multiple wall jet.However,when the radial spacing is greater than 30 m,the radial spacing has no obvious influence on the energy dissipation effect.When radial spacing is greater than or equal to 20 mm and the perforation spacing is less than 80 mm,the hole spacing has little influence on the energy dissipation effect,and the optimum radial distance is 10 m,the distance between the two holes is 4m.Furthermore,with the increase of the momentum flux ratio,the energy dissipation effect is better,but when the momentum flux ratio is greater than 0.6,the energy dissipation effect is basically the same,which can be applied in practical engineering.5.In practical engineering,when the hole spacing is less than or equal to 4m,the bigger the aperture ratio is,the better the energy dissipation effect is;When the hole spacing is 5m,the energy dissipation effect is better when the aperture ratio is 1.67;When the hole spacing is 6m,the aperture ratio should be less than 0.3,and the aperture ratio should be less than 0.35 when the hole spacing is 7m.