# Pelton Lab

```1. OBJECTIVES
To test the Pelton Turbine at different loads and spear valve settings and produce curves that
show the turbine performance and the effect of different spear valve settings.
2. METHODOLOGY
1. Create three blank results table.
2. Adjust the spring balances to give no load and make sure that they show 0 (zero).
3. Fully shut the spear valve (turn it fully clockwise).
4. Start the hydraulic bench and slowly open its control valve while opening the spear
valve (turn it anticlockwise) until the bench flow is at maximum and the spear valve is
fully open.
5. Use the Hydraulic Bench to measure the initial flow for reference. Note the inlet
pressure.
6. Use the optical tachometer to measure the maximum (no-load) speed of the turbine.
To do this, put the tachometer against the clear window at the back of the turbine and
use it to detect the reflective sticker on the drum.
7. Slowly increase the load in steps to give at least six sets of results. At each step, record
the turbine speed and the reading of each spring balance. Stop when the speed
becomes unstable or the turbine stops rotating.
8. Repeat the test with the spear valve approximately half (50%) open and approximately
quarter (25%) open. The exact amount of spear valve opening is not important, as long
as long they are different from each other to compare the effect.
DATA COLLECTION
50%
Speed
(rev/min)
Left Balance (N) Right Balance (N) (Nm)
Power (W)
Efficiency (%)
328.98
0
0
0
0
0
221.66
0.2
0.4
0.0065
0.1509
40.45
203.47
0.25
0.5
0.008125
0.1731
46.41
177.25
1.5
2
0.01625
0.3016
80.86
131.22
1.6
2.2
0.0195
0.2675
71.72
101.82
1.75
2.7
0.0308
0.329
88.25
62.28
2.25
3
0.0244
0.159
42.62
26.73
2.5
3.7
0.039
0.109
29.27
0
3.25
4.6
0.043875
0
0
DATA ANALYSIS
After computations were made below are the graphs for 50% thrust showing Speed VS torque,
Power and efficiency, respectively.
SPEED VS TORQUE
Speed (rev/min) VS Load (Torque) (Nm)
0,05
0,045
0,04
0,035
0,03
0,025
0,02
0,015
0,01
0,005
0
0
50
100
150
200
250
300
350
SPEED VS POWER
Speed (rev/min) VS Power (W) Power (W)
350
300
250
200
150
100
50
0
0
2
4
Speed (rev/min)
6
Power (W)
8
10
SPEED VS EFFICIENCY
Speed (rev/min) VS Efficiency (%)
100
90
80
70
60
50
40
30
20
10
0
0
50
100
150
200
250
300
350
```