Centrifugal pump design and analysis
Objective:
To design a centrifugal pump and Obtain the relationship between Pressure ratio and mass flow rate
Description:
Centrifugal pump:
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, from which it exits
Simulation:
A simulation is an approximate imitation of the operation of a process or system; that represents its operation over time. Simulation is used in many contexts, such as simulation of technology for performance tuning or optimizing, safety engineering, testing, training, education, and video games.
flow trajectory:
In fluid mechanics, metrology, and, oceanography a trajectory traces the motion of a single point, often called a parcel, in the flow.
Model:
Parameters:
Internal flow simulation
Steady-state study
Pressure: 101325KPa
Temperature: 293.2K
Medium: Water
Rotation: On and 1000 rad/s
Boundary conditions:
Inlet pressure: 101325KPa
Outlet velocity at exit: 10m/s
Procedure:
- First, create a 3d model of the centrifugal pump.
- The Rotating Region is selected and the speed is set to 1000 rpm.
- The Inlet Boundary Condition is set as an Environmental Pressure of 1 bar.
- The Outlet Boundary Condition is the Exit Velocity of 15 m/s.
- The Surface Goal is set in the Inlet and the Outlet faces.
- Then the Mesh is created for the model and the Automatic mesh level is set into 3 and Advanced Chanel refinement is selected.
- Run the Simulation and the cut plots are created for the Pressure and Velocity and get the values for the goals.
- Then open parametric study then type the output parameters as 10,20,30,40,50 and provide all the value and plot the graph
Design parametric study:
The design parametric study has been conducted with 5 levels and they are 10,20,30,40,50 and the above goals and plots are obtained.
Design point at 10 m/s:
velocity:
pressure:
Velocity-flow trajectory:
pressure-flow trajectory:
Design point at 20 m/s:
velocity:
pressure:
Velocity-flow trajectory:
pressure-flow trajectory:
Design point at 30 m/s:
velocity:
pressure:
Velocity-flow trajectory:
pressure-flow trajectory:
Design point at 40 m/s:
velocity:
pressure:
Velocity-flow trajectory:
pressure-flow trajectory:
Design point at 50 m/s:
velocity:
pressure:
Velocity-flow trajectory:
pressure-flow trajectory:
Final results:
Parametric study:
Plot-1 inlet pressure:
Plot-2 outlet pressure:
Mass flow rate:
Pressure Vs Mass flow rate:
Flow trajectory video:
Result:
Hence the simulation is performed by using flow simulation and the above result is obtained and,
- The negative sign is due to the outlet region. 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.