Project

Centrifugal pump design and analysis

Objective: To create a centrifugal pump and analyze the performance by observing the mass flow rate and pressure ratio.

Definitions:

Pressure ratio: Outlet total pressure/ Inlet total pressure.
Mass flow rate: In physics and engineering, it is the mass of a substance which passes per unit of time. It is a scalar quantity.
Centrifugal Pump: They are a sub-class of dynamic axisymmetric work-absorbing turbomachinery. They are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow.

Dimensions:

Procedure:

Initially, a Centrifugal Pump Model is created as per suggestion given in course videos.
Lids were created at both ends of the pump so that the model can be watertight.
Local region (averaging) rotation type and water as fluid are selected.
Rotational speed is set to 1000 rpm.
The boundary conditions are set as Environmental Pressure of 101325 Pascal’s at the inlet lid and exit velocity of 15m/s at the outlet lid.
Exit velocity is taken as inlet parameter for the parametric study within a range of 15-25m/s.
Automatic mesh level-3 with advance channel refinement is selected.
Surface goals, Flow trajectories, Cut plots are set as per requirement and number of iterations is set to 500.
Finally, the Simulation is run and the results are obtained.

Results:

At velocity: 15m/s,

At velocity: 17.5m/s,

At velocity: 20m/s,

At velocity: 22.5m/s,

At velocity: 25m/s,

Velocity normal to face (Outlet Velocity 1) [m/s]	15	17.5	20	22.5	25
Avg Inlet Total Pressure[Pa]	325183.6115	455051.3412	173078.673	606929.4597	722607.0402
Avg Outlet Total Pressure [Pa]	2787559.793	4040623.188	1876612.132	3831903.293	3659534.707
SG Mass Flow Rate [kg/s]	-0.739033413	-0.855105532	-0.989130312	-1.104709678	-1.21509238
Pressure Ratio	8.572264082	8.879488582	10.84253824	6.313589218	5.064349644

Animations:

At velocity: 15m/s

Observation:

As we know mass flow rate is directly proportional to the velocity, so if the outlet velocity increases the mass flow rate increases with it.
The mass flow rate obtained is negative at the outlet that is because mass leaving the body is always taken as negative whereas the mass entering the body is taken as positive.
For the comparison purpose, positive values of mass flow rate are used.
Pressure ratio fluctuations are due to the interaction between the impeller and the volute casing.
In this study, we did not use the splitters, but the use of splitter blades decreases the pressure fluctuations because it allows a better circumferential pressure distribution.
The number of blades also has a huge impact on pump efficiency and total pressure, the perfect number of blades can be found experimentally.

Ship work like this
in your own course.