Centrifugal pump design and analysis
Aim: Perform CFD analysis of centrifugal pump
Objective:
- create the 3-D model of centrifugal pump
- perform CFD analysis of centrifugal pump
- perform parametric study by increasing mass flow rate
- obtain performance diagram
Therotical Background:
Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow. The rotational energy typically comes from an engine or electric motor. They are a sub-class of dynamic axisymmetric work-absorbing turbomachinery The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward into a diffuser or volute chamber (casing), from which it exits.
Common uses include water, sewage, agriculture, petroleum and petrochemical pumping. Centrifugal pumps are often chosen for their high flow rate capabilities, abrasive solution compatibility, mixing potential, as well as their relatively simple engineering. A centrifugal fan is commonly used to implement a vacuum cleaner. The reverse function of the centrifugal pump is a water turbine converting potential energy of water pressure into mechanical rotational energy.
Geometry of problem:
Input data:
- Fluid: Water
- Flow type : Internal
- Rotation : Local region averaging
Boundary conditions :
Inlet : environmental pressure=101325 pascal
outlet: mass flow rate /outlet velocity=10m/s
Procedure:
- create the 3-D model of centrifugal pump
- create simulation with flow simulation
- use moving referance method
- angular velocity of volume around impeller is 1000 radian/second
- define boundary condition
- insert goal that we want and run simulation
- perform parametric study by varrying outlet velocity
Data obtained:
|
Design Point 1 |
Design Point 2 |
Design Point 3 |
Design Point 4 |
Design Point 5 |
|
|
Velocity normal to face(Outlet Velocity)[m/s] |
10 |
15 |
20 |
25 |
30 |
|
SG Av Total pressure1[Pa] |
1200657.68 |
1836805.587 |
735977.1723 |
9959994.6128 |
507948.8129 |
|
SG Mass Flow Rate 1 [kg/s] |
-0.443914859 |
-0.664423617 |
-0.887430155 |
-1.100701987 |
-1.332325356 |
|
Outlet Velocity |
Pressure Ratio |
Mass Flow Rate (Kg/s) |
|
10m/s |
11.84957 |
0.443915 |
|
15m/s |
18.12786 |
0.664424 |
|
20m/s |
7.26353 |
0.88743 |
|
25m/s |
9.829703 |
1.100702 |
|
30m/s |
5.013065 |
1.332325 |
Cut plot:
Conclusion:
- As mass flow rate increases the pressure ratio attains maximum and the decreases with increase in mass flow rate
- At low velocity / low mass flow rate we can attain maximum pressure ratio
Result:
- CFD analysis of Centrifugal pump has been done successfully.