Feb 26, 2016

Feb 26, 2016

Feb 26, 2016

# An Experiment on Hydraulic Jump

## Objectives of the experiments:

1. To create the hydraulic jump.

2. To verify the questions of fluid flow.

3. To determine the slatrility & characteristics of the hydraulic jump obtained in the lab using Impulse momentum & specific energy equations.

4. To compare measured flow depths with theoretical results.

## Theoretical background:

Hydraulic jumps are very efficient in dissipating the energy of the flow to make it more controllable & les erosive. In engineering practice, the hydraulic jump frequently appears downstream from overflow structures (spillways), or under flow structures (slvice gates), where velocities are height. A hydraulic jump is formed when liquid at high velocity discharges into a zone of lower velocity only if the 3 independent velocities (y1, y2, fr1) of the hydraulic jump equation conform to the following equation:

Y2 = y1/2 [-1+√1+8Fr2 ]

Fr2 = 92/9y3

## Apparatus:

• Glass walled flume with sluice gates & a spillway arrangement
• Point gauges
• Manometer & scales
• Pump

Also See: Water Hammer

## Procedure for Hydraulic Jump Experiment:

1. I started the pump to supply water to the flume.

2. Then I closed the tail gate to allow water to accumulate and to develop hydraulic jump.

3. I adjusted the position of the hydraulic jump by adjusting the amount of closure of slvice gate.

4. I then measured the depth of the bed of flume by using a point gauge.

5. In the next step , I measured water surface level before it had crossed the spillway.

6. Then I measured height of spillway & the depth of water over the spillway.

7. Using the point gauges I then determined the water surface levels downstream of the jump.

8. Then I measured y1 & y2.

9. I repeated the measurement steps again for a different flowchart.

## Results:

 S.No Hm(m) Y1(mm) Y2(mm) Lj(m) H(mn) H1(mn) H2 1 0.8 342 46 2 6.5 24 106 0.45

## Sources of errors:

### Human errors:

1. Errors occurred during measurements i.e. by taking erroneous reading of depths or in micrometer.
2. Errors occurred in operation of slvice gates.

### Instrumentation error:

• Leakage from the flume
• Assumptions of ideal conditions did not prevail:
• Ideal conditions which prevailed in the theoretical equations were not there and frictional forces also had some effect on the experiment.