Week 9 - Parametric study on Gate valve.

Aim:- We have to perform a parametric study on the gate valve simulation by setting the opening from 10 % to 80%.

• Obtain the mass flow rates at the outlet for each design point.
• Calculate the flow coefficient and flow factor for each opening and plot the graph.
• Discuss the results of the mass flow rate and flow coefficient.

Objective:- Perform the parametric study on gate valve and analyse the mass flow rate and plot the velocity countour.

Thoery:-gate valve, also known as a sluice valve, is a valve that opens by lifting a barrier (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

Main parts of Gate valve

1. bonnet

2. spindle

3. gate disk

4. flange

5. handle wheel

CFD:-Computational fluid dynamics or CFD is the analysis of systems involving fluid flow, heat transfer and associated phenomena such as chemical reactions by means of computer-based simulation.

Practical application in current scenario

• aerodynamics of aircraft and vehicles: lift and drag
  • hydrodynamics of ships
  • power plant: combustion in internal combustion engines and gas
  turbines
  • turbomachinery: flows inside rotating passages, diffusers etc.
  • electrical and electronic engineering: cooling of equipment including
  microcircuits
  • chemical process engineering: mixing and separation, polymer moulding
  • external and internal environment of buildings: wind loading and
  heating/ventilation
  • marine engineering: loads on off-shore structures
  • environmental engineering: distribution of pollutants and effluents
  • hydrology and oceanography: flows in rivers, estuaries, oceans
  • meteorology: weather prediction
  • biomedical engineering: blood flows through arteries and veins

CFD Work Flow:- CFD codes are structured around the numerical algorithms that can tackle fluid flow problems. In order to provide easy access to their solving power all commercial CFD packages include sophisticated user interfaces to input problem parameters and to examine the results

Its threee step process
(i) a pre-processor

involves defination of geometry, grid generation, selection of phenomenon that need to model

(ii) a solver

intergration of governing equation, discretisation and solution

(iii) a post-processor

ploting of contour, graphs and making movies.

In solving fluid flow problems we need to be aware that the underlyingphysics is complex and the results generated by a CFD code are at best asgood as the physics (and chemistry) embedded in it and at worst as good asits operator with CFD

Solving and Modeling Approch:-

There are no way present to understand and analyse the effeciveness of the mixiing tee model.

1. analytical approch

2. simulation approch

3. experimental approch

using analytical approch and experimental approch is time consuming and high cost senario. this could be eliminated by using simulation approch in which we can analyse the system with the actual codition we are intrested in.

To do this we are using ansys fluent solver

we are using fluid flow analysis using Fluent solver because we are interested in the total effectiveness of the fluid in the mechnical tee model, here we are using two different models to analyse the effectiveness of the mixing of fluid.

Approch we are using.

1. We need to open Ansys workbench

2. Choose the Appropiate Solver

3. Assign Appropiate name

4. Choose geometry and select new spaceclaim model.

5. Load the appropiate file

6. Implement the geometrical operation

7. Apply the mesh and provide name selection

8. Choose setup, select the appropiate model

9. Initalisation and running the simulation

10. Result making i.e. countour plots graphs

1. Opening Ansys workbench

2. Choose the Appropiate Solver

now extract the volume.

now suppress the solid parts for physics

We done with geometry part

5. Meshing

for meshing we uses the default mesh length

Provide name selection

6. Setup

Settings

Solver	Steady State
Energy Equation	Off
Model	Laminar,RNZ<SWRIL>Standard
Inlet	Pressure Inlet
Outlet	Pressure Outlet
Material_(Fluid)	Water
Cell Zone Condition	Water
gravity	Enable in Z direction -9.81m/s^2

it will create mass flow rate as parametric outlet

Now we can run the simulation for 200 iteration.

7. Parametric Window

8.Result

For 10mm lift

Velocity contour	Velcoity Vector

For 20mm lift

Velocity contour	Velcoity Vector

For 30mm lift

Velocity contour	Velcoity Vector

For 40mm lift

Velocity contour	Velcoity Vector

For 50mm lift

Velocity contour	Velcoity Vector

For 60mm lift

Velocity contour	Velcoity Vector

For 70mm lift

Velocity contour	Velcoity Vector

For 80mm lift

Velocity contour	Velcoity Vector

Inferences:-

1. as we increase the valve opening we find that mass flow rate increases

2. as we increase the valve opening we find that velocity decreases

3. as we increases the valve opening overall pressure increases.