Exp 5 Head Loss Due To Friction 2014
MEHB221
Fluids Mechanics Lab
2014
Experiment No. 5
HEAD LOSS DUE TO PIPE FRICTION
Objective
To verify that Darcy-Weisbach equation can be used to predict the head loss due to friction with flow of water through a smooth bore pipe.
Apparatus
Fluid Friction Apparatus, FM100.
Hydraulic Bench, FM110.
Summary of theory
For water flowing through a circular pipe, the head loss due to the friction can be calculated using Darcy-Weisbach equation. h = 4fLu2
2gd
Or h = λLu2
2gd
Where
L = length of pipe between tappings (m) = 1m for all pipes d = internal diameter of the pipe (m) u = mean velocity of water through the pipe (m/s) g = 9.81 (acceleration due to gravity,m/s2 ) f = pipe friction coefficient [ (British) 4f = λ (American) ]
The value of Reynolds number Re can be calculated using this equation:
Re = ρud µ Where (assume temperature = 20ºC) µ = dynamic viscosity = 1.002 x 10-3 kg/m.s ρ = density = 998 kg/m3
1
MEHB221
Fluids Mechanics Lab
2014
Procedures
1.
2.
3.
4.
5.
6.
Open fully the flow control valve and inlet isolating valve.
Make sure that gate valve and globe valve are closed.
Switch on the main switch for hydraulic bench and digital pressure indicator.
Open fully the outlet control valve.
Open the isolating valve for the test pipe No. 1.
Insert the two manometer tubes (from digital pressure indicator) into the tapping valve of pipe No. 1.
7. Switch on the pump of hydraulic bench.
8. Let the water flow through the system for a while.
9. Note down the reading on the differential pressure indicator.
10. Close the drain, use a stopwatch to time a certain amount of water flowing into the measuring tank and calculate the flow rate.
11. Once it is done, open the drain and let the water flow into the sump tank.
12. Change the flow rate of water by adjusting outlet control valve to get different differential pressure reading.
13. Again, take the differential pressure reading and measure the flow rate.
14. Obtain at least six readings for various flow rates.
Fluids Mechanics Lab
2014
Experiment No. 5
HEAD LOSS DUE TO PIPE FRICTION
Objective
To verify that Darcy-Weisbach equation can be used to predict the head loss due to friction with flow of water through a smooth bore pipe.
Apparatus
Fluid Friction Apparatus, FM100.
Hydraulic Bench, FM110.
Summary of theory
For water flowing through a circular pipe, the head loss due to the friction can be calculated using Darcy-Weisbach equation. h = 4fLu2
2gd
Or h = λLu2
2gd
Where
L = length of pipe between tappings (m) = 1m for all pipes d = internal diameter of the pipe (m) u = mean velocity of water through the pipe (m/s) g = 9.81 (acceleration due to gravity,m/s2 ) f = pipe friction coefficient [ (British) 4f = λ (American) ]
The value of Reynolds number Re can be calculated using this equation:
Re = ρud µ Where (assume temperature = 20ºC) µ = dynamic viscosity = 1.002 x 10-3 kg/m.s ρ = density = 998 kg/m3
1
MEHB221
Fluids Mechanics Lab
2014
Procedures
1.
2.
3.
4.
5.
6.
Open fully the flow control valve and inlet isolating valve.
Make sure that gate valve and globe valve are closed.
Switch on the main switch for hydraulic bench and digital pressure indicator.
Open fully the outlet control valve.
Open the isolating valve for the test pipe No. 1.
Insert the two manometer tubes (from digital pressure indicator) into the tapping valve of pipe No. 1.
7. Switch on the pump of hydraulic bench.
8. Let the water flow through the system for a while.
9. Note down the reading on the differential pressure indicator.
10. Close the drain, use a stopwatch to time a certain amount of water flowing into the measuring tank and calculate the flow rate.
11. Once it is done, open the drain and let the water flow into the sump tank.
12. Change the flow rate of water by adjusting outlet control valve to get different differential pressure reading.
13. Again, take the differential pressure reading and measure the flow rate.
14. Obtain at least six readings for various flow rates.