Parametric study on Gate valve

Introduction:

Gate valve can be defined as a type of valve that uses gate disks and the disk moves perpendicular to the flow to start or stop the flow in a piping.

It is the most commonly used valve in the industry. These valves are either in fully open or closed condition. when the gate valve is fully opened, the disk is completely removed. In this position there is no obstruction in the flow, due to this there will be no pressure drop accross the gate valve.

Geometry setup:

The given gate valve geometry contains only solid boundary. The inlet and outlet portions of the domains were also given short to study effect of the flow across the gate valve. Therefore, first the inlet and outlet portions were extended using pull option. Then, the fluid volume was extracted using appropriate edges. Then using the move option the disk of the gate valve was moved upwards by 10 mm. The move was parametrized to conduct parametric study.

The parametric study was conducted for different positions of gate valve given below:

• 0 mm
• 5 mm
• 10 mm
• 15 mm
• 20 mm
• 25 mm

The geometry setup for the gate valve is given below:

Original Geometry:

Extended geometry:

Extracted fluid volume:

Mesh:

Mesh size: 7 mm

No of cells: 376718

Simulation setup:

The setup for the simulation was done in FLUENT. The setup was run for 300 iterations. the setup used a gravity enabled model with viscosity model as k-epsilon (realizable). Average mass flow rate was calculated at the outlet and was also parametrized. After the completion of the simulation the parametric study was conducted.

Inlet conditions:

Gauge pressure inlet: 10 pa

outlet conditions:

Gauge pressure outlet: 0 pa

Operating conditions:

absolute pressure: 101320 pa

Simulation results:

Case 1: 0 mm

Geometry:

animation:

Case 1: 5 mm

Geometry:

animation:

Case 1: 10 mm

Geometry:

animation:

Case 1: 15 mm

Geometry:

animation:

Case 1: 20 mm

Geometry:

animation:

Results:

The mass flow rates for different cases of gate valve are:

• 0 mm = -0.102 kg/s
• 5 mm = -0.123 kg/s
• 10 mm = -0.148 kg/s
• 15 mm = -0.188 kg/s
• 20 mm = -0.236 kg/s