Centrifugal Pump Demonstration Unit: Energy Efficiency and Conservation

CENTRIFUGAL PUMP DEMONSTRATION UNIT
(CH3132 - Energy Efficiency and Conservation)

INSTRUCTED BY

: Mr. M.A. THARANGA NAME INDEX NO GROUP DATE OF PER DATE OF SUB : T.R.MUHANDIRAMGE : 090334 H :E : 2012-03-30 : 2012-04-24

RESULTS AND DISCUSSION Exercise 1 :-Understanding the basic characteristic curves of a centrifugal pump.
1. Total head against the flow rate

At 70% At 50%

2. Mechanical power changes with the flow rate

At 70% At 50%

3. Pump efficiency against the flow rate

At 70% At 50%

Predicted head and predicted flow rate
Using affinity laws we can predict the flow rate and total head values of the pump when it is operating at the 50% speed, using values obtained at 70% speed.

1

2

n1 - The pump speed (n1=70) n2 - The pump speed of the predicting occasion (n2=50) Q1 - The flow rate at n1 speed (L/s) Q2 - The flow rate at n2 speed (L/s) - (predicting value) Ht1 - The total head at n1 speed (m) Ht2 - The total head at n2 speed (m) – (predicting value)

Flow rate at 70% experimented data
0.00 0.13 0.20 0.29 0.40 0.49 0.58 0.69 0.80 0.90 1.00 1.14

Flow rate at 50% predicted data
0.000 0.095 0.142 0.209 0.285 0.352 0.417 0.494 0.569 0.645 0.711 0.816

Head at 70% experimented data
3.63 3.68 3.66 3.55 3.56 3.49 3.49 3.40 3.28 3.15 2.96 2.62

Head at 50% predicted data
1.851 1.879 1.869 1.812 1.817 1.780 1.779 1.733 1.671 1.610 1.508 1.337

The comparison between the predicted values obtained from affinity laws and the measured vales (total head against flow rate graph) at 50% pump efficiency

Predicted data Experiment data

Theoretical curves for total head, mechanical power and efficiency

DISCUSSION
1) Compare the head, power and the efficiency curves obtained with the theoretical curves and discuss about the similarities and the differences. Three graphs were plotted using the values obtained from the practical which were total Head, power. And the efficiency against the flow rate at different pump