Gate valve simulation parametric study

In this project, a gate valve is simulated and a parametric study is conducted to measure the mass flow rate at the outlet for different lift conditions of the gate disc. A gate valve uses a gate disc to control the water flow, the gate valve is usually adjusted by a hand wheel. First, the geometry of the gate valve is modified by extruding the pipe portion both sides by 800mm. Then the gate valve is moved up by using the move function and component selector, it is moved by 5mm initially. This distance of the upward movement is called the lift of the gate disc. The lift of the gate disc is parametrised and the fluid volume is extracted by using the update in context option. After the fuid volume extraction all the solid geometries are supressed for physics. The fluid volume is then meshed by giving an element size of 0.006m. A steady state simulation is carried out with gravity enabled to act along z-axis with a value of -9.81m/s^2. Under the materials tab water is added and the cell zone condition is updated to water as water flow is to be simulated. Then the air under materials tab is deleted. A pressure of 10Pa is given at inlet by selecting inlet as pressure-inlet. A realizable k-epsilon model with scalable wall function is used for turbulence modelling. Then under definitions a flux report is defined to calculate mass flow rate from the outlet, this flux report is also set as output parameter. The solution is intialized using standard method with inlet as reference and the simulation is run. After this, parameters is opened in workbench and the necessary lift value is given to get the respective output parameter.

Geometry from which the fluid volume is extracted:

Mesh:

Number of nodes in the mesh is 83642 and the number of elements is 413274.

The outputs obtained after simulation from the parametric simulation for various lift values:

For 5mm lift design point the outlet mass flow rate is : -0.12313kg/s

5mm lift geometry cross-section:

5mm lift velocity contour animation:

For 10mm lift design point the outlet mass flow rate is : -0.14958kg/s

10mm lift geometry cross-section:

10mm lift velocity contour animation:

For 15mm lift design point the outlet mass flow rate is : -0.18965kg/s

15mm lift geometry cross-section:

15mm lift velocity contour animation:

For 20mm lift design point the outlet mass flow rate is : -0.23957kg/s

20mm lift geometry cross-section:

20mm lift velocity contour animation:

For 25mm lift design point the outlet mass flow rate is : -0.29926kg/s

25mm lift geometry cross-section:

25mm lift velocity contour animation:

From the results we can see that the mass flow rate increases as the lift increases, but the sign is negative because fluent reports the flow leaving from the pipe or an enclosed geometry to free space as negative.