Assessing the safety of shut-off elements

A difficulty during the assessment of safety shut-off elements for hydro plants is that the exact impacts are unknown. Loads occur which are difficult to estimate, particularly during highly transient states such as pipe rupture. Using modern CAE tools, the behaviour of the flow in the penstock pipes can be investigated more precisely. The coupling of the pressure surge and the CFD simulation make it possible to investigate pressure surge and flow problems for entire hydro plants and to calculate the corresponding boundary conditions for the CFD simulation. The results of the CFD simulation then indicate the hydrodynamic and hydrostatic effects on the shut-off element.