Innovative gates for reduction of hydrodynamic forces

Abstract

High head gates are required to resist and operate under high head conditions. Due to the value of the hydraulic vertical load the design of the gate is a matter of special concern. Those special forces occur during operation of gates.<br />This dissertation contributes with new geometrical design approach. The new type of construction was tested in Laboratory of Hydraulic Engineering Institute, University of Technology Vienna. Appropriately scaled model experiments were effectively used to evaluate the hydrodynamic performance of a gate system for different boundary conditions. Those are gate slots depth, distance between upstream or downstream gate leaf face and wet well wall, different water heads and opening ratios.<br />Besides experimental investigation at the, a commercial CFD program (Ansys) has been applied for calculation of hydrodynamic forces. The evaluated results of experiments were compared with the results of the numerical solution. For the investigated gate type a good agreement between the numerical results and the test results was obtained.<br />Finally the result of this effort is the gate which safely operates and closes with assistance negative downpull forces. The downpull forces reduction amounts up to 90%. There is no risk of appearance of negative downpull forces which inhibit closure or cause catapulting action. The innovative gates are very usefull in practice of gate design