Centrifugal pump design and analysis

Aim - To design a Centrifugal pump and simulate the Flow and obtain Pressure drop, Pressure Ratio and Mass Flow rate.

Obtain performance diagram and obtain the relationship between Pressure ratio and mass flow rate and explaination of results.

• Pressure ratio = Outlet total pressure/ Inlet total pressure.

Objective - To understand the relation between Pressure and MAss Flow rate.

The dimensions of the pump are as follows.

• The diameter of the Volute casing is 90 mm.
• The thickness of the Volute casing is 15 mm.
• Rotary blade diameter is from 40mm to 80mm.
• A number of blades=5.
• The diameter of the inlet suction cylinder is 30 mm.
• Length of the inlet suction cylinder is 80 mm.
• The diameter of the delivery pipe is 10 mm.
• The shell of thickness 1mm is made.
• Water is considered as working fluid.
• Surface roughness is taken as zero.
• Gravity is not considered.
• Internal type of simulation is taken.
• The rotational feature is considered in this analysis.

Geometry -

Boundary conditions

• Inlet suction pipe is maintained at environmental pressure [101325 Pa].
• The outlet discharge pipe is maintained at some velocity 10 [m/s].
• A domain or cylindrical structure is made around the rotor which completely covers the rotor from all the sides.
• The dimensions of the domain, diameter 86mm and thickness 11mm.
• A rotational feature which was considered for analysis is given to this domain.
• The rotational speed of this domain is 1000 rad/sec.

A parametric study is done considering the input parameters such as Velocity normal to the face taking 6 values between 10m/s to 30m/s. They are 10, 14, 18, 22, 26, 30 m/s respectively.. Output parameters obtained are Total pressure at inlet Total pressure at outlet and outlet and mass flow rate.

We need to control the Calculation Creteria thi is important because if we set it to default, we will not get good results so we are setting the iteration here, and we will be providing a value of 500.

Results: -

Parameteric study: -

(equation goal = pressure ratio as legend) in parameteric study

here at

design point 1 = outlet flow velocity is 10 m/s

design point 2 = outlet flow velocity is 14 m/s

design point 3 = outlet flow velocity is 18 m/s

design point 4 = outlet flow velocity is 22 m/s

design point 5 = outlet flow velocity is 26 m/s

design point 6 = outlet flow velocity is 30 m/s

parameteric study goal table: -(equation goal is pressure ratio)

plot between mass flow rate and pressure ratio: -

plot for pressure ratio corresponding to the parameteric design point: -

Design point 1: -

velocity contour

pressure contour

flow trajectory

Design point 2: -

velocity contour

pressure contour

flow trajectory

Design point 3: -

velocity contour

pressure contour

flow trajectory

Design point 4: -

velocity contour

pressure contour

flow trajectory

Design point 5: -

velocity contour

pressure contour

flow trajectory

Design point 6: -

velocity contour

pressure contour

flow trajectory

Conclusion: - we can see that velocity defined at the outlet is not constant as well (some flow lines are in different color) meaning that those are having different values as well.

Another thing is that, Due to improper/bad design of pupm we can see from the flow trajectory that there are some line at the shaft, which are not behaving as the other trails, resulting in flow disturbance, but as it is minor and dosent affect the overall flow pattern,we an neglect it.

At last point of design we can see that the results is very different as expectation. This is also due to ba design of pump.