1. Internal Incompressible
Introduction to Fluid Mechanics
Chapter 8
Internal Incompressible
Viscous Flow
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2. Main Topics Entrance Region Fully Developed Laminar Flow 
Between Infinite Parallel Plates
Fully Developed Laminar Flow in a Pipe
Turbulent Velocity Profiles in
Fully Developed Pipe Flow
Energy Considerations in Pipe Flow
Calculation of Head Loss Solution of Pipe Flow Problems Flow Measurement   
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3. Entrance
Region
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4. Daerah berkembangnya profil kecepatan dari linier di hulu menjadi parabolik disebut entrance region, sedangkan daerah dengan profik kecepatan berbentuk parabolik disebut fully developed region.

5. Fully Developed Laminar Flow Between Infinite Parallel Plates
Both
Plates
Stationary
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6. Problems 8.1
Standar air enters a 150 mm diameter duct. Find the volume flow rate at which the flow becomes turbulent. At this flow rate, estimate the entrance length required to establish fully developed flow

7. Fully Developed Laminar Flow Between Infinite Parallel Plates
 Both Plates Stationary
Plates •
Transformation of
Coordinates
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8. Fully Developed Laminar Flow Between Infinite Parallel Plates
 Both Plates Stationary
Plates •
Shear Stress
Distribution •
Volume Flow
Rate
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9. Fully Developed Laminar Flow Between Infinite Parallel Plates
 Both Plates Stationary •
Flow Rate as a Function of Pressure
Drop •
Average and Maximum Velocities
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10. Fully Developed Laminar Flow
Between Infinite Parallel Plates
 Upper Plate Moving with Constant Speed, U
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11. Problems 8.9
Viscous oil flow steadily between parallel plates. The flow is fully developed and laminar. The pressure gradient is 1,25 kPa/m and the channel half-width is h = 1,5 mm. Calculate the magnitude and direction of the wall shear stress at the upper plate surface. Find the volume flow rate through the channel (μ = 0,50 Ns/m²)

12. Problems 8.23
Two immiscible fluids are contained between infinite parallel plates. The plates are separated by distance 2h, and the two fluid layers are of equal thickness h; the dynamic viscosity of the upper fluid is three times that of the lower fluid. If the lower plate is stationary and the upper plate moves at constant speed U = 6,1 m/s, what is the velocity at the interface? Assume laminar flows, and that the pressure gradient in the direction of flow is zero.

13. Fully Developed Laminar in a Pipe Flow
Velocity Distribution
Flow
Shear
Stress
Distribution
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14. Fully Developed Laminar Flow in a Pipe Rate Volume Flow Flow Rate as
Function of
Pressure
Drop
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15. Fully Developed Laminar in a Pipe Flow
Average Velocity
Flow
Maximum
Velocity
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16. Turbulent Velocity Profiles in Fully Developed Pipe Flow
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17. Turbulent Velocity Profiles in Fully Developed Pipe Flow
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18. Problems 8.47
A hypodermic needle, with inside diameter d = 0,127 mm and length L = 25 mm, is used to inject saline solution with viscosity five times that of water. The plunger diameter is D = 10 mm; the maximum force that can be exerted by a thumb on the plunger is F = 33,4 N. Estimate the volume flow rate of saline that can be produced.

19. Calculation of Head
Loss
Major
Losses:
Friction
Factor
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20. Calculation of Head Loss Factor Laminar Friction Turbulent Friction
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21. Calculation of
Head
Loss
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22. Calculation of Head Loss
 Minor Losses •
Examples: Inlets and Exits; Enlargements and
Contractions;
Pipe
Bends;
Valves
and
Fittings
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23. Le Calculation of Head Loss Minor Loss: Loss Coefficient, K Minor
Equivalent
Length, Le
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24. Calculation
of Head Loss
Pumps,
Fans,
and
Blowers
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25. Calculation of Head Loss Noncircular Ducts Example: Rectangular Duct
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26. Solution of Pipe Flow
Problems
Energy
Equation
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27. Solution of Pipe
Flow
Problems
Major
Losses
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28. Solution of Pipe
Flow
Problems
Minor
Losses
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29. Problems 8.73
Water flows from a horizontal tube into a large tank. The tube is located 2.5 m below the free surface of water in the tank. The head loss is 2 J/kg. Compute the average flow speed in the tube.

30. Problems 8.84
Water flows through a 25 mm diameter tube that suddenly enlarges to a diameter of 50 mm. the flow rate through the enlargement is 1,25 Liter/s. Calculate the pressure rise across the enlargement. Compare with the value for frictionless flow.

31. Flow Measurement  Direct Methods•
Examples: Accumulation in a Container;
Positive Displacement Flow meter
 Restriction Flow Meters for Internal Flows •
Examples: Orifice Plate;
Flow
Nozzle;
Venturi;
Laminar
Flow
Element
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32. Flow Measurement  Linear Flow Meters •
Examples: Float Meter (Rotameter);
Turbine;
Ultrasonic
Vortex;
Electromagnetic;
Magnetic;
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33. Flow Measurement  Traversing Methods • Examples: Pitot (or Pitot
Static)
Tube;
Laser
Doppler
Anemometer
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34. Problems 8.173
A venture meter with a 762 mm diameter throat is place in a 152 mm diameter line carrying water at 24˚C. The pressure drop between the upstream tap and the venture throat is 305 mm of mercury. Compute the rate of flow.