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MAJOR ASSIGNMENT SUBJECT-R.A.C.
TOPIC –ANALYSIS OF CENTRIFUGAL PUMP
SUBMITTED BY SUBMITTED TO
MOHAMMAD SHAHBAZ MR. ADITYA MISHRA
U.I.D.-K10611 ASST. PROFESSOR M.E.
BRANCH-M.E. DEPT. CPU
WHAT IS CENTRIFUGAL PUMP?
WORKING MECHANISM OF A CENTRIFUGAL PUMP
POWER AND EFFICIENCY CALCULATION.
COMPONENTS OF CENTRIFUGAL PUMPS
ADVANTEGAES AND DISADVANTAGES OF CENTRIFUGAL PUMPS
Convert the mechanical energy into hydraulic energy by centrifugal force on the liquid
Constitute the most common type of pumping machinery
Used to move liquids through a piping system
Has two main components:
1. Stationary componets, casing, casing cover and bearings2. Rotating components, impeller and shaft
Classified into three categories ; Radial Flow, Mixed Flow, Axial Flow
Simplest piece of equipment in any process plant
Energy changes occur by virtue of impeller and volute
Liquid is fed into the pump at the center of a rotating impeller and thrown outward by centrifugal force
The conversion of kinetic energy into pressure energy supplies the pressure difference between the suction side and delivery side of the pump
Liquid flow path inside a centrifugal pump
•The power supplied to the pump:
Where m=mass flow rate, kg/s H= total discharge head, N.m/kg =efficiency
…………(1)
•The power delivered to the fluid:
…………(2)
•From equations (1) and (2) efficiency:
nq is the specific speed for a unit machine that is geometric similar to a machine with the head Hq = 1 m and flow rate Q = 1 m3/s
43q HQ
nn
qs nn 55,51
Three basic components:
Volute, casing, bodyor Diffuser
Impelleror impellers
Driver (motor)
Centrifugal Pumps
Vanes
Direction ofrotation
Centrifugal Pumps
• Open• Semi-open• Closed
- Single suction- Double suction
• Non-clogging• Axial flow• Mixed flow
Maximum efficiency lies in the range:
2000<NS<3000High head, low capacity
pumps:500<NS<1000
Low head, large capacity pumps:
NS>15000
Centrifugal Pumps
Rotation
Impeller
Blades
Vt
V
r
V
s
Vr = Radial Velocity
Vt = Tangential Velocity
Vs = Vector Sum Velocity
Centrifugal Pumps
Suction Eye
Cutwater
Arrows represent thedirection of water flow Discharge
Nozzle
Advantages
Simple in construction and cheapHandle liquid with large amounts
of solidsNo metal to metal fitsNo valves involved in pump
operationMaintenance costs are lower
Disadvantages
Cannot handle highly viscous fluids efficiently
Cannot be operated at high headsMaximum efficiency holds over a
narrow range of conditions