Validation cases are the best way to evaluate how a numerical simulation compares to a physical problem that has been measured experimentally. In this blog post, we will review two important performance parameters for incompressible flow through an industrial scale butterfly valve; the flow coefficient (Cv) and the torque coefficient (CT).
Valve Geometry
Meshing of the Butterfly Valve
A 3D hexahedral SnappyHexMesh was used and refinement was done in three places: upstream, downstream, and in the vicinity of the valve. A layer mesh was used on all wall regions for more accuracy.

Simulation Setup
Tool Type: OpenFOAM
Analysis Type: Incompressible Steady State
Turbulence Model: k–omega SST
Fluid: Water (ν =10-6 m2/s)
Boundary Conditions:
Results of the Validation
A comparison of the flow coefficient (Cv) and the torque coefficient (CT) over the opening angle ranging from 20 to 85 degrees can be seen in the plots below.
From these plots, it can be seen that the performance parameter values from the numerical analysis performed on the SimScale platform match well with the experimental values from the team of Xue Guan Song [1].

This validation case is freely available in the SimScale Public Projects library and can be found and imported into your workspace here.
To avoid large data, the import project only contains results for angles 20, 50 and 85 degrees.
Discover all the simulation features provided by SimScale. Download the document below.
References
- Xue Guan Song, Young Chul Park NUMERICAL ANALYSIS OF BUTTERFLY VALVE: PREDICTION OF FLOW COEFFICIENT AND HYDRODYNAMIC TORQUE COEFFICIENT Proceedings of the World Congress on Engineering and Computer Science 2007 WCECS 2007 October 24-26, 2007 San Francisco USA.