CFD ANALYSIS OF CFD ANALYSIS OF CENTRIFUGAL PUMPCENTRIFUGAL PUMP

By: Dipak Pandey 10BME025

Pavan Patel 10BME031

Pujan Shah 10BME039

Guided By: Prof. S.V. Jain

Outline of PresentationOutline of Presentation

• Introduction• Objectives of Present Studies• Solid and Fluid Model• Meshing• Result and Discussion• Grid In-dependency• Cavitation Analysis

ObjectiveObjective

• CFD analysis of Centrifugal Pump in pump mode for different flow conditions in Fluent and Ansys CFX.• To plot the characteristics curves and compare it with

the model testing results.• CFD analysis of Centrifugal Pump in pump mode with

cavitation.

IntroductionIntroduction

Centrifugal Pump• Due to centrifugal action pressure is developed and it will lift

the fluid to certain height• It is widely used in industry as well as domestic level

Cavitation in pumpCavitation in pump• Cavitation can be define as the breakdown of a liquid

medium under very low pressures into vapour

Phase diagram of waterPressure plot for impeller section

Specification of PumpSpecification of Pump

Parameter Value

Rated Head 15 m

Discharge 1500 LPM

Speed 1500 RPM

Power 4.5 kW

Suction flange dia.

75 mm

Delivery flange dia.

100 mm

Impeller dia. 250 mm

TypeMedium speed, Centrifugal, Volute casing

Pump taken for CFD Analysis

(Source- Lubi Pumps)

Solid Model of Casing and Solid Model of Casing and ImpellerImpeller

Computational DomainComputational Domain

MeshingMeshingType Tetrahedral Grid

Spacing 2mm

No. of Elements in Casing 11,55,478

No. of elements in Impeller

8,10,301

Total No. of Elements 19,65,779

Spacing Elements

10 34588

5 178366

3 689111

2.7 942615

2.5 1111607

2 1965779

Data for mesh of interval 2 mm

Mesh of interval 2 mm in Gambit

Boundary ConditionsBoundary ConditionsBoundary Condition

Mass flow (kg/s) Po given (Pa)

22 170000

25 164000

26 162000

28 158000

29 152000

32 130000

34 103000

Performance curves for Pump

Pressure PlotsPressure Plots

Velocity PlotVelocity Plot

Grid IndependencyGrid Independency

Grid Independency

Spacing Elements Max Efficiency Deviation

10 34588 82.63407767 -7.409788226

5 178366 85.44033325 -4.265422058

3 689111 88.20820798 -1.16406104

2.7 942615 89.11992282 -0.142498594

2.5 1111607 88.52044789 -0.81420102

2 1965779 89.24709868 0

Vapour volume fractionVapour volume fraction

29 kg/s BEP22 kg/s Part load 34 kg/s Overload

Pressure Plot ComparisonPressure Plot Comparison

Performance CurvesPerformance Curves

Patel and Ramakrishnan [1]

Performance CurvesPerformance Curves

Patel and Ramakrishnan [1]

Performance CurvesPerformance Curves

Patel and Ramakrishnan [1]

ConclusionsConclusions

• For backward curved vanes centrifugal pump increase in mass flow rate Head decreases, Input and Output power increases

• Efficiency first increases with discharge, reach maximum efficiency at rated discharge and then decreases

• Input power required in CFD is less than model testing because leakage and friction loss are not considered.

• Maximum efficiency is found at 0.029 m3/s which is 89.24%.• In cavitation mode efficiency is 66.95%• Due to cavitation efficiency of pump reduces because for pumping of vapour more

power is required• Also due to cavitation head developed by pump is less because vapour has less density

than water

ReferencesReferences

1. Patel K and Ramakrishnan N, “CFD Analysis of Mixed Flow Pump”

Thank YouThank You