Development of a parallel relief valve synchronized with Francis guidevanes

The design of a parallel relief valve synchronized with Francis turbine guidevanes was successfully developed, as a result of research in Slovenia. Various insertions for the valve were developed to change the flow rate characteristic with no effect on synchronization with the guidevane hydraulic oil cylinder. Flow in the valve was numerically analysed for several openings and for three insertions. The parallel relief valve was installed at several powerplants and the case of a small hydro plant in Uganda is presented here.