Modeling, CFD and FEM Calculations of a Pressure Control Valve
Sector: Energy supplySpecialist field: Fluid mechanics, Structural mechanicsGrande Dixence S.A. in Sion (Switzerland) is a leading supplier of electrical power and owner of the Grande Dixence dam in the Valaisian Alps, one of the tallest gravity dams in the world. They have to perform a design review for the maintenance of several pressure control valves, part of which is an analysis using Ansys Workbench.
Summary
Task
The devices are quite old, and the present working conditions have changed since their installation. It is therefore necessary to know the response of the structure due to the new water flow conditions.
Solution
The geometry was created with Ansys DesignModeler based on 55-year-old construction drawings. The pressure field obtained from the Ansys CFD calculation was used as the load condition on the FE model. This allowed the calculation of the stress field in the structure using Ansys Mechanical.
Customer benefits
With the contribution from CADFEM (Suisse) AG, Grande Dixence S.A. now knows the flow behavior in the pressure control valve and the structural response due to the new operating conditions.
Project Details
Task
Grande Dixence S.A. in Sion (Switzerland) is a leading supplier of electrical power and owner of the Grande Dixence dam in the Valaisian Alps, one of the tallest gravity dams in the world. They have to perform a design review for the maintenance of several pressure control valves (large hydraulic installations that evacuate water in case of overpressure in the pipes). These devices are quite old and the present working conditions have changed since their installation. It is therefore necessary to know the response of the structure due to the new water flow conditions. In order to understand this behavior, a coupled one-way fluid-structure simulation was performed.
Solution
The geometry was created with Ansys DesignModeler based on 55-year-old construction drawings. The fluid domain, including the downstream pipe section was then transferred to Ansys CFX. The new operating conditions were used to determine the model boundary conditions. With this CFD simulation, the pressure field in the fluid volume and on the internal walls of the ducts was calculated. In order to assess the structural integrity, a Finite Element Model (FE model) based on the structure of the device was built. The concrete surrounding the pipework was also considered. The pressure field obtained from the CFD calculation was used as the load condition on the FE model. This allowed the calculation of the stress field in the structure using Ansys Mechanical.
Customer Benefit
With the contribution from CADFEM (Suisse) AG, Grande Dixence S.A. now knows the flow behavior in the pressure control valve and the structural response due to the new operating conditions. This allows Grande Dixence SA to identify the most sensitive zones of the structure, which have to be carefully checked during the design review.
Images: © Grande Dixence