Design and analysis of Centrifugal Pump using SolidWorks
Aim:
To design and analyze the flow within a Centrifugal Pump using SolidWorks.
Objective:
- To create a 3D model of a centrifugal Pump using SolidWorks.
- Then to run a Parametric Study for different velocities.
- Then to obtain the relationship between Pressure ratio and mass flow rate i.e., Performance diagrams for the analysis.
Theory:
Centrifugal pump is a hydraulic machine which converts mechanical energy into hydraulic energy by the use of centrifugal force acting on the fluid. These are the most popular and commonly used type of pumps for the transfer of fluids from low level to high level.
It is used in places like agriculture, municipal (water and wastewater plants), industrial, power generation plants, petroleum, mining, chemical, pharmaceutical and many others.
When a certain mass of liquid is made to rotate by an external source, it is thrown away from the centrifugal axis of rotation and a head is impressed which enables it to rise to a higher level. Centrifugal Pumps can be used for viscous and non-viscous liquids and has higher efficiency.
Software Used:
SolidWorks
CAD Model Dimensions:
- Impeller Diameter = 0.02 m
- Outer casing Diameter = 0.04 m
- Inlet pipe Diameter = 0.015 m
- Outlet pipe Diameter = 0.01 m
- Inlet pipe Length = 0.07 m
- Outlet pipe length = 0.075 m
- Shell Thickness = 0.001 m
Procedure :
- Initially a 3Dmodel of Centrifugal Pump with given input dimensions is designed having a total numbers of blades equal to 5.
- In order to setup flow inside the model, Lids are created at both ends of inlet and outlet.
- Then Flow Simulation Add on is chosen
- Then a new project in flow simulation is created.
- The Working fluid is set as Water and Rotation is selected.
- Then the rotating speed of the region equal to 1000rad/s is set.
- The Boundary conditions at Inlet is set as Environmental pressure 1 bar and Outlet as outlet velocity as 10 m/s.
- The surface goals of mass flow rate and total pressure at inlet, total pressure at outlet to find pressure ratio is inserted.
- A parametric study is performed to obtain the pressures for various outlet velocity values, Simulation is done with the velocity values of 10m/s, 15m/s, 20m/s, 25m/s, 30m/s in Input variables to study its nature.
- For Output parameters the surface goal of total pressure inlet , surface goal of total pressure outlet, surface goal of mass flow rate at 1 kg/s, and the Cut plot of pressure and velocity is added to the study.
- Flow Trajectories for Pressure and Velocity is inserted to evaluate results.
- Finally the obtained results are plotted.
CAD Model:
Results:
1.PARAMETRIC STUDY:
1.1.Case(1) At Velocity = 10m/s:
Pressure Plot
Velocity Plot
1.2.Case(2) At Velocity = 15m/s:
Pressure Plot
Velocity Plot
1.3.Case(3) At Velocity = 20m/s:
Pressure Plot
Velocity Plot
1.4.Case(4) At Velocity = 25m/s:
Pressure Plot
Velocity Plot
1.5.Case(5) At Velocity = 30m/s:
Pressure Plot
Velocity Plot
There is always a low velocity and pressure region near the impeller in all the cases and this is due to the water being pushed from that region due to rotation of impeller.
The negative results is due to the sign convention of water going out of the fluid domain. The mass flow rate is considered as positive here.
2.GOAL PLOTS (Performance diagram):
2.1. Velocity vs mass flow rate:
2.2. Velocity vs pressure ratio:
2.3. Mass flow rate and Pressure ratio at all five studies:
Pressure ratio = Outlet total pressure/ Inlet total pressure
References:
- https://en.wikipedia.org/wiki/Centrifugal_pump
- https://www.powerzone.com/resources/glossary/centrifugal-pump
Conclusion:
From the First plot it could be initially seen that, the velocity is small and so the mass flow rate is also small, when the velocity increases the mass flow rate also increases. Velocity is directly proportional to the mass flow rate.
Outlet velocity is inversely proportional to pressure as outlet velocity increases, the total average outlet pressure value gets decreased.