Hydraulic structure for water flow control

Abstract

A hydraulic structure having walls ( 1 ) creating a downstream narrowing passage in a streaming surface water. The downstream ends ( 4 ) of the walls ( 1 ) are edged in order to generate vortices ( 2 ) dissolving from the edges ( 4 ) downstream which dissipate the energy of the flow created by a level difference between the entry and the exit of the passage.

1 . Hydraulic structure for water flow control in a running surface water, wherein two wall members constitute a water passage effectively narrowing downstream, the ground of the bed of the surface water decreases downstream in the passage, and the downstream end of at least one of the wall members constitutes an edge after which the width of the bed is effectively widened so that the energy of flow of the height difference of the ground between the ground upstream and downstream is dissipated by essentially vertical vortices created at or near the edges. 
     
     
         2 . The hydraulic structure according to  claim 1 , wherein a section thereof comprising the passage is constructed as a minimum energy loss (MEL) structure until the water surface has dropped to the intended level. 
     
     
         3 . Hydraulic structure according to  claim 1 , wherein the wall members are substantially impermeable to water. 
     
     
         4 . Hydraulic structure according to  claim 1 , wherein the wall members are substantially vertically erected with respect to the direction of flow. 
     
     
         5 . Hydraulic structure according to  claim 1 , wherein front surfaces of the wall members which front surfaces create the passage have an about mirror-symmetrical shape with respect to the streaming direction of the surface water. 
     
     
         6 . Hydraulic structure according to  claim 1 , wherein the edge at the downstream end of the wall member has an angle of at least 30° with respect of the main direction of the flow. 
     
     
         7 . Hydraulic structure according to  claim 1 , wherein after the downstream ends of the wall members the bed of the surface water is widened at least up to the width of the entry of the passage. 
     
     
         8 . Hydraulic structure according to  claim 1 , wherein the narrowing of the passage and the sloping of the ground is substantially continuous. 
     
     
         9 . Hydraulic structure according to  claim 1 , wherein the wall members are essentially convex towards the passage. 
     
     
         10 . Hydraulic structure according to  claim 1 , wherein the backside of at least one of the wall extends by at least 80° to the front surface of the wall members with regard to the direction of stream of the water in order to create a space of calm water behind the wall member, the angle being defined in the plane of the surface of the water. 
     
     
         11 . Hydraulic structure according to  claim 1 , wherein in the passage a fish pass is arranged the bottom of which constitutes the deepest level in the passage so that in case of even low water, at first the fish pass if provided with water. 
     
     
         12 . Hydraulic structure arrangement comprising at least two hydraulic structures according to  claim 1  in one or more of a parallel arrangement, a consecutive arrangement, and an arrangement where at least two hydraulic structures are placed in stacked manner, with the stacked hydraulic structures laid out for different water levels. 
     
     
         13 . Hydraulic structure arrangement according to  claim 12 , wherein at least two hydraulic structures differ in at least one of width, length depth, so that the hydraulic structure arrangement is capable to deal with an enlarged range of flow rate or volume flow of the surface water. 
     
     
         14 . Hydraulic structure according to  claim 1 , wherein a hydroelectric device is present, the hydroelectric device having an inlet at the upstream end of the passage or further upstream, and an outlet at the downstream end of the passage or further downstream so that the hydroelectric device can generate electric current in using the level difference upstream and downstream of the hydraulic structure. 
     
     
         15 . Hydraulic structure according to  claim 1 , wherein the edge at the downstream end of the wall member has an angle of at least 60° with respect of the main direction of the flow. 
     
     
         16 . Hydraulic structure according to  claim 1 , wherein the edge at the downstream end of the wall member has an angle of at least 90° with respect of the main direction of the flow. 
     
     
         17 . Hydraulic structure according to  claim 1 , wherein the edge at the downstream end of the wall member is substantially constituted by a blade like element. 
     
     
         18 . Hydraulic structure according to  claim 1 , wherein the backside of at least one of the wall extends by at least 90° to the front surface of the wall members with regard to the direction of stream of the water in order to create a space of calm water behind the wall member, the angle being defined in the plane of the surface of the water. 
     
     
         19 . Hydraulic structure according to  claim 1 , wherein the backside of at least one of the wall extends about parallel to the front surface of the wall members with regard to the direction of stream of the water in order to create a space of calm water behind the wall member, the angle being defined in the plane of the surface of the water.