Centrifugal Pump Essay

Sargam Jain

13110109

Group: G

CHARACTERISTICS OF CENTRIFUGAL PUMP

1. Abstract

The purpose of this experiment was to obtain characteristic (head, power, and efficiency) curves of given centrifugal pump at constant speed and the correlations would be very helpful for the performance prediction of pump working as turbine.

2. Introduction

Centrifugal pumps are mainly used to flow liquid through the piping system. It is best for the situations requiring variation in flow rates (moderate to high). The main characteristic curves of a centrifugal pump are total head (H) developed, power consumed and thee efficiency plotted as a function of the flow

3. Procedure

Opened the valves on the suction and discharge lines of the pump after filling the water reservoir to about 90% of its capacity and then switched on the pump. Adjusted the speed (R.P.M.) of the pump to make it sure that the rpm of pump remain within ±50 of 6000 rpm and then noted down the suction and discharge manometer readings. Then the valve at the bottom of the calibrated tank was closed and noted the time required for the water to rise between two marks using a stopwatch. As soon as the water level reaches the top mark the valve was opened and the energy meter reading was taken. Repeated the whole experiment with by increasing discharge pressure till it reaches the maximum discharge pressure.

4. Observations & Results Energy meter when pump is run empty (kW1) = 0.014 kW Height difference between suction and discharge pressuring tapings (Z) = 93 cm Volume of calibrated tank (V) = 12 ltr

Observation

= (m ̇*H)/75*735.3

Brake horse power of the pump

B.H.P= [kW_2 ]-[kW_1 ]

Efficiency of the pump

"η = " (F.H.P.)/(B.H.P.)*100

Table of Calculated Results

Obs. No Mass flow rate of water, m ̇

(Kg/sec) Volumetric flow rate of water, Q

(L.P.M.) Total head developed, H

(m) F.H.P

(W) B.H.P

(W) Efficiency, "η"

(%)

1 0.109 6.545 1.522 15.95 82 19.46

2 0.107 6.429 2.266 23.32 83 28.10

3 0.103 6.154 2.883 28.41 83 34.23

4 0.098 5.902 3.526 33.32 82 40.63

5 0.094 5.669 4.193 38.07 83 45.87

6 0.090 5.373 4.975 42.80 81 52.84

7 0.085 5.070 5.718 46.43 80