TITLE: ENERGY LOSS IN PIPE AND FITTINGS

OBJECTIVE:

Ø To determine the loss of head due to friction in incompressible flow in a horizontal pipe

Ø To determine the friction factor of a pipe

Ø To determine the loss of head in sudden expansion and sudden contraction of pipe

Ø To determine the loss coefficient in sudden expansion and sudden contraction of pipe

Ø To determine the losses of energy (head losses) in different configuration of pipes

THEORY:





L


Bernoulli’s Equation:


v1 = v2 = v constant diameter pipe

= pressure head at 1

= pressure head at 2

= horizontal pipe

FRICTION LOSS (DARCY’S EQUATION)

Where:

F is friction factor

L is length of the pipe

V is velocity of the flow in the pipe

D is the inside diameter of the pipe

G is the gravitation acceleration and

Losses in sudden expansion and sudden contraction of pipe

Bernoulli’s equation:

(Pressure heat at 1)

(Pressure heat at 2)

(Horizontal Pipe)

Where :

= is the cross-section area of the pipe at section 1

= is the cross-section area of the pipe at section 2

Loss Coefficient

Continuity equation


Q=A1v1=A2v2 v1=(A2/A1)v2

APPARATUS:

Ø Adjustable measurement system

Ø Back wall

Ø Ball cocks for shutting off part sections.

Ø Double pressure gauge

Ø Drain

Ø Inlet (concealed)

Ø Measurement object-flow measurement

Ø Measurement object-shut-off devices

Ø Tubular steel frame with suction pads

PROCEDURES:

Part A: Loss of Head Due to Friction in PVC 20 x 1.5 pipes

1. Temperature of the room was recorded.

2. The length and inside diameter of the pipe were recorded.

3. All valves were closed except those that will let the water flows from the tank to section pipe 2 and return back to the tank. The direction of the flow in the pipe was verified.

4. Manometer hoses were connected to the pressure tapping points of the pipe.

5. The pump was switched on. Air bubbles were removed from the apparatus.

6. the valve on the left side of the pipe was adjusted in order to have the difference of manometer level of 10mm. The value was recorded.

7. The volume flow rate (Q) was measured and recorded.

8. Steps 6 and 7 were repeated for the difference of manometer level of 20mm, 40mm, 80mm, 120mm, 160mm, 240mm.

Part B: Flow Through Sudden Expansion of Pipe from PVC 20 x 1.5 pipes to

PVC 32 x 1.8 pipes

1. Inlet and throat diameters of the pipe 1 were recorded.

2. All valves were closed except those that will let the water flows from the tank to

section pipe 1 and return back to the tank. The direction of flow in the pipe 1 was verified.

3. The manometer hoses were connected to the pressure tapping points of the pipe 1.

4. The pump was switched on. Air bubble was removed from the apparatus.

5. The valve was adjusted on the left side of the pipe 1 to a certain position.

6. The valve of h1 and h2 were measured and recorded.

7. The actual volume flow rate (Q actual).

8. Step 6 to 8 for 5 values of Q actual were repeated.

Part C: Flow Through Sudden Contraction of Pipe from PVC 32 x 1.8 pipes to

PVC 20 x 1.5 pipes

1. Inlet and throat diameters of the pipe 2 were recorded.

2. All valves were closed except those that will let the water flows from the tank to

pipe 2 and return back to the tank. The direction of flow in the pipe 2 was verified.

3. The manometer hoses were connected to the pressure tapping points of the pipe 2.

4. The pump was switched on. Air bubble was removed from the apparatus.

5. The valve was adjusted on the left side of the pipe 2 to a certain position.

6. The valve of h1 and h2 were measured and recorded.

7. The actual volume flow rate (Q actual).

8. Step 6 to 8 for 5 values of Q actual were repeated.

DATA AND CALCULATION:

Part A: Loss Of Head Due to Friction In PVC 20x1.5 Pipe

Pipe length

L = 800 mm

= 0.8M

Pipe inside diameter

d =17mm

= 0.017M

Pipe cross-section area

A= 0.502

Volume measure

Time observed

Q

V

Measure No.

(lites)

(s)

(lites/s)

(

(

(mm)

(mm)

(mm)

(m)

1

1

14.03

0.0713

59.9

58.8

1.1

0.0011

2

1

14.00

0.0714

60.5

58.5

2.0

0.002

3

1

11.37

0.0880

62.1

58.1

4.0

0.004

4

1

8.97

0.1115

65.8

57.5

8.3

0.0083

5

1

8.91

0.1122

69.0

57.0

12.0

0.012

6

1

8.10

0.1235

72.5

56.5

16.0

0.016

7

1

6.81

0.1468

78.5

55.5

23

0.023

Part B: Loss Of Head Due to Sudden Expansion of Pipe from PVC 20 x 1.5 pipes to

PVC 32 x 1.8 pipes

Upstream pipe inside diameter

Volume measure

Time observed

Q

V

Measure No.

(lites)

(s)

(lites/s)

(

(

(mm)

(mm)

(mm)

(m)

1

1

14.03

0.0713

59.9

58.8

1.1

0.0011

2

1

14.00

0.0714

60.5

58.5

2.0

0.002

3

1

11.37

0.0880

62.1

58.1

4.0

0.004

4

1

8.97

0.1115

65.8

57.5

8.3

0.0083

5

1

8.91

0.1122

69.0

57.0

12.0

0.012

6

1

8.10

0.1235

72.5

56.5

16.0

0.016

7

1

6.81

0.1468

78.5

55.5

23

0.023

DISCUSSION

Through the experiment, the objective had been achieved and as follows:

o To determine the loss of head due to friction in incompressible flow in a horizontal pipe where from the experiment, the data is______ while from theoretical calculation is______.

o To determine the friction factor of a pipe where from the experiment, the data is______ while from theoretical calculation is______.

o To determine the loss of head in sudden expansion and sudden contraction of pipe where from the experiment, the data is______ while from theoretical calculation is______.

o To determine the loss coefficient in sudden expansion and sudden contraction of pipe where from the experiment, the data is______ while from theoretical calculation is______.

o To determine the losses of energy (head losses) in different configuration of pipes where from the experiment, the data is______ while from theoretical calculation is______.

CONCLUSION

  • As a conclusion the experiment were successfully carried out, even though the data collected are varies with theoretically equation because the different are minute and can be negligible.

  • The different between experiment data theoretically equation are mainly due to human and servicing factors such as:

a. Parallax error – occur during captured the value of water level, h1 and h2.

b. Bubble inside the pipe line was not properly flushed during bleeding.

  • The are no relative motion between the fluid particles. The only stress will be normal stress which is equal to the pressure.

RECOMMENDATION

There are a lot of possibilities for an experiment will having an error and as per discuss above. Therefore it is recommendation are as follows:

a. Change to the new equipment and apparatus.

b. Built the platform when taking the parallax error.