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