MEHB221

Liquids Mechanics Lab

2014

Experiment No . your five

HEAD REDUCTION DUE TO PIPE FRICTION

Objective

To confirm that Darcy-Weisbach equation can be used to predict the top loss due to friction with flow of water through a smooth lose interest pipe.

Device

Fluid Friction Apparatus, FM100.

Hydraulic Table, FM110.

Synopsis of theory

For water flowing by using a circular water pipe, the head damage due to the scrubbing can be determined using Darcy-Weisbach equation.

h = 4fLu2

2gd

Or perhaps

h sama dengan О»Lu2

2gd

Where

T = duration of pipe between tappings (m) = 1m for all water lines

d = internal diameter of the water pipe (m)

u = imply velocity of water through the pipe (m/s)

g = 9. seventy eight (acceleration as a result of gravity, m/s2 )

farreneheit = pipe friction agent [ (British) 4f = О» (American) ]

The value of Reynolds number Re may be calculated employing this equation: Re = ПЃud

Вµ

Wherever (assume temp = 20ВєC)

Вµ = dynamic viscosity = 1 ) 002 x 10-3 kg/m. s

ПЃ = density = 998 kg/m3

1

MEHB221

Fluids Mechanics Lab

2014

Methods

1 .

2 .

3.

some.

5.

6.

Open fully the circulation control valve and inlet isolating device. Make sure that gateway valve and globe valve are shut down.

Switch on the main switch pertaining to hydraulic bench and digital pressure indication. Open totally the outlet control valve.

Wide open the separating valve to get the test tube No . 1 .

Insert both manometer pipes (from digital pressure indicator) into the tapping valve of pipe Number 1 .

several. Switch on the pump of hydraulic counter.

8. Let the water circulation through the system for a while.

on the lookout for. Note down the reading within the differential pressure indicator. 15. Close the drain, use a stopwatch to time a great amount of water moving into the testing tank and calculate the flow price.

11. When it is carried out, open the drain and let the water movement into the sump tank. doze. Change the stream rate of water by simply adjusting wall socket control valve to acquire different differential box pressure studying.

13. Again, take the differential pressure examining and gauge the flow level. 14. Attain at least six psychic readings for different flow prices.

15. Turn off the pump and shut the isolating valve for test tube No . 1 . 16. Duplicate the above techniques for evaluation pipe Number 2 (repeat procedures four to 14). 17. Turn off the pump and close the separating valve intended for test water pipe No . 2 . 18. Duplicate the above procedures for check pipe Number 3.

19. Switch off the pump and shut the isolating device for evaluation pipe No . 3. 20. Switch off the main switch and shut the inlet separating valve.

Info, Observation and Results

п‚·

п‚·

Record the effects on the effect sheet provided.

Calculate the flow price (Q), speed (u) and Reynolds amount (Re).

To get

Q sama dengan V by 10-3

To

And

u = 4Q

ПЂd2

п‚·

Calculate the friction element (f) making use of the following formula then calculate О»: Intended for laminar stream

f sama dengan 16

Re

2

MEHB221

Fluids Mechanics Lab

For turbulent flow

п‚·

2014

f sama dengan 0. 079

Re0. 25

Calculate the theoretical mind loss together with the following formula: h sama dengan О»Lu2

2gd

п‚·

Estimate the percentage mistake between the assumptive and experimental values.

п‚·

Plot the graph of friction element, f vs . Reynolds number, Re for each test water line in one graph (Graph 1).

Analysis and Discussion

п‚·

п‚·

п‚·

п‚·

Explain about head loss in pipe (including head damage due to friction). Comment on the end result and compare the assumptive with the trial and error values. Comment on Graph one particular and evaluate your graph with the moody diagram. List the possible sources of errors and security precaution.

Consequence Sheet

Volume

V

[L]

Time

T

[s]

Stream

rate (Q)

[ m3/s ]

Velocity

u

[ m/s ]

Re

farrenheit

О»

Test out pipe Number 1 size = zero. 006 m

Test water pipe No . two diameter sama dengan 0. 010 m

Evaluation pipe No . 3 size = zero. 017 m

Theoretical

mind (hth)

[ meters H2O ]

Exp. head

loss (hexp)

[ millimeter H2O ]

Pipe length M = you m

3

Exp. head

loss (hexp)

[ m WATER ]

Percent

Problem

[%]

MEHB221

Fluids Technicians Lab

4

2014

MEHB221

Fluids Technicians Lab

almost 8

1

2014

9...