Gate Valve Parametric Study
Title: Parametric study on a Gate Valve.
Objective:
To perform a parametric study on a given Gate valve geometry to obtain and compare the mass flow rates at various lift parameters ranging from 10 to 90 mm.
Theory:
Gate valve:
A gate valve is a valve that opens by lifting a barrier or gate out of the path of the fluid. Gate valves require very little space along the pipe axis and hardly restrict the flow of fluid when the gate is fully opened. Gate valves are used to shut off the flow of liquids rather than for flow regulation. When fully open, the typical gate valve has no obstruction in the flow path, resulting in very low flow resistance. The size of the open flow path generally varies in a nonlinear manner as the gate is moved. This means that the flow rate does not change evenly with stem travel. Depending on the construction, a partially open gate can vibrate from the fluid flow.
This particular simulation was performed in four cases depending upon the lift of the valve.
Case 1: Gate valve lift = 10 mm.
Case 2: Gate valve lift = 30 mm.
Case 3: Gate valve lift = 60 mm.
Case 4: Gate valve lift = 90 mm.
Procedure:
Step 1: Geometry:
The given Gate valve geometry is as follows:
The faces of inlet and outlet are pulled to 800 mm.
The fluid volume is extracted using edge selection.
For the simulation the lift of the gate valve must be given in spaceclaim using move option for the valve itself and then is parametrised.
Case 1: Lift = 10 mm.
Case 2: Lift = 30 mm.
Case 3: Lift = 60 mm.
Case 4: Lift = 90 mm.
Step 2: Meshing.
The mesh settings are the same for all the cases, but as the geometry changes so does the mesh.
Step 3: Setup & Solution.
Parameter: Lift of the Gate valve.
Solver type: Pressure based.
Time: Steady.
Gravity: Along -ve Z axis.
Turbulence model: k-epsilon, Realizable.
Materials used: Water liquid.
Boundary conditions: Inlet: 10 Pa.
Definitions: flux- mass flow rate- create output parameter.
No. of iterations: 250.
Step 4: Results.
Case 1: Lift = 10 mm.
Residual plot:
Mass flow rate plot:
Velocity contour:
Case 2: Lift = 30 mm.
Residual plot:
Mass flow rate plot:
Velocity contour:
Case 3: Lift = 60 mm.
Residual plot:
Mass flow rate plot:
Velocity contour:
Case 4: Lift = 90 mm.
Residual plot:
Mass flow rate plot:
Velocity contour:
Image of the parametric tab:
Conclusion:
- Parametric study of a system helps in drastically decreasing the simulation time taken to perform simulation on each parameter.
- From the above results, it can be said that, with the increase in the gate valve lift the mass flow rate also increases. The negative value of the mass flow rate indicates the fluid leaving the system.
- With each lift parameter the fluid volume changes, thus changing the No. of elements in the mesh.