Strengthen The Crescent Rib Steel Fork Tube Fluid-structure Interaction Analysis

Bifurcation is one of the key components of underground project of hydroelectric station, whose design has received highly recognition all through the ages for its complicated structure form and stress condition. With the development of high-head, deep-bury hydroelectric station and storage hydroelectric station in recent years, the design of bifurcation is more and more important and arduous in order to satisfy the large size of bifurcation. Steel bifurcations with inner crescent rib is widely used for underground bury pressure pipe for its less head loss, uniform stress distribution, smooth outer and small excavating cross-section. Today, there are two common-use calculation methods for the design of bifurcation, one is structural mechanics method and the other is finite element method, some project has used structural mechanics method for design and finite element method for checking. However, these methods do not consider the interaction of fluid and solid and the flow in bifurcation.Thus, the research achievements of bifurcation, the design method of steel bifurcations with inner crescent rib, the calculation of water hammer, the k-εturbulent model, the SIMPLEC method and the calculation principal of fluid-solid interaction are introduced in this paper. Furthermore, the numeric simulation of steel bifurcations with inner crescent rib considerating fluid-solid interaction in normal condition and water hammer condition are done through commercial finite element software ADINA.The achievements are listed as follow according to the calculation results of ADINA:(1) The discrete model of Steel bifurcations with inner crescent rib is established.(2) The water hammer varies from the shutdown time of the gate of the pressurepipe in hydroelectric station, and the fluid-solid interaction calculation of Steelbifurcations with inner crescent rib is finished according to the different water hammer situation for response.(3) The turbulent flow field of Steel bifurcations with inner crescent rib under fluid-solid interaction condition is analyzed by using the k - e turbulent model.(4) The crescent rib has an optimizational effect on the stress distribution of Steel bifurcations with inner crescent rib. Based on the calculation results, the crescent rib can restrain the deformation of Z direction of Steel bifurcations with inner crescent rib for the max stress occurs in the crescent rib.