Design and Analysis of Air Release Valve for High Pressure Hydro Power Plants

The combination valves are extensively used in hydro power plants to protect the penstock pipe during filling or emptying process. The project consists of design, development & validation of Air release valve/ Anti vacuum valves for pressure rating PN40 and for a size of 80mm valve. During initial filling of penstock, the water which flows into the empty penstock, displaces the air & pushes it to be higher elevation. If the air at this location is not removed from Penstock the flowing water compress the air to such an extent that penstock pipe may burst. Similarly during emptying of penstock pipe, the penstock pipe has to be filled with air at a rate equal to emptying rate. In the absence of air supply, vacuum is created & the penstock pipe collapses. Hence all Hydro power plants irrespective of the power generating capacity is compulsorily required to use this device to protect penstock pipe. The present research focuses on three main factors: 1) Effect of loads acting on pressure release valve, 2) Linear static analysis and bilinear analysis will be carried by applying boundary conditions using ANSYS software. The linear static analysis is carried out to know the structure is safe at certain value of pressure acting on valve.