FACULTY: ENGINEERING EDITION:

TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:
FACULTY OF ENGINEERING TECHNOLOGY
DEPARTMENT OF CHEMICAL ENGINEERING TECHNOLOGY

FLUID MECHANICS LABORATORY

LABORATORY INSTRUCTION SHEETS

COURSE CODE BNQ 10304

EXPERIMENT NO. EXPERIMENT 4

EXPERIMENT TITLE OSBORNE REYNOLDS DEMONSTRATION

DATE
GROUP NO.
LECTURER/INSTRUCTOR/ 1)
TUTOR 2)
DATE OF REPORT
SUBMISSION
ATTENDANCE/PARTICIPATION/DISCIPLINE: /5%
INTRODUCTION: /5%
PROCEDURE: /5%
RESULTS& CALCULATIONS /15%
ANALYSIS /15%
DISTRIBUTION OF MARKS
FOR LABORATORY DISCUSSIONS: /20%
REPORT: ADDITIONAL QUESTIONS /15%
CONCLUSION /10%
SUGGESTIONS& RECOMENDATIONS /5%
REFERENCES: /5%
TOTAL: /100%

EXAMINER COMMENTS: RECEIVED DATE AND STAMP:

 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT

KOD ETIKA PELAJAR DATE:

(KEP)
JABATAN TEKNOLOGI KEJURUTERAAN KIMIA

FAKULTI TEKNOLOGI KEJURUTERAAN

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saya sendiri. Saya juga mengaku tidak menerima atau memberi sebarang bantuan dalam

menyediakan laporan ini dan membuat ikrar ini dengan kepercayaan bahawa apa-apa yang

tersebut di dalamnya adalah benar.

Ketua Nama:

Kumpulan No. Matriks:

(Tandatangan)

Ahli 1 Nama:

No. Matriks:

(Tandatangan)

Ahli 2 Nama:

No. Matriks:

(Tandatangan)

Ahli 3 Nama:

No. Matriks:

(Tandatangan)

Tarikh :________________________________
 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:

1.0 OBJECTIVES

1. To compute Reynolds number (Re).

2. To observe the laminar, transitional and turbulent flow.

2.0 LEARNING OUTCOMES

Demonstrate the ability to conduct experiments related to fluid flow by following standard operating
procedure effectively in a group.

3.0 INTRODUCTION / THEORY

The Osborne Reynolds Demonstration has been designed for students experiment on the laminar, transition and turbulent flow. It
consists of a transparent header tank and flow visualization pipe. The header tank is provided with a diffuser and stilling materials
at the bottom to provide a constant head of water to be discharged through a bell mouth entry to the flow visualization pipe. Flow
through this pipe is regulated using a control valve at the discharge end. The water flow rate through the pipe can be measured
using the volumetric tank (or volumetric cylinder). Velocity of the water can therefore be determined to allow the calculation of the
Reynolds Number. A dye injection system is installed on top of the header tank so that flow pattern in the pipe can be visualized.

The theory is named in honor of Osborne Reynolds, a British engineer who discovers the variables that can be used as a criterion
to distinguish between laminar and turbulent flow.

The Reynolds number is widely used dimensionless parameters in fluid mechanics.

UL
Reynolds number formula: R 
V

R = Reynolds number
U = Fluid velocity, (m/s)
L = characteristic length or diameter (m)
V = Kinematic viscosity (m2/s)

Reynolds number R is independent of pressure

 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:

3.1 Pipe Flow Conditions

For water flowing in pipe or circular conduits, L is the diameter of the pipe. For Reynolds number less than 2100, the pipe flow
will be laminar. For Reynolds number from 2100 to 4000 the pipe flow will be considered a transitional flow. Turbulent occur
when Reynolds number is above 4000. The viscosity of the fluid also determines the characteristic of the flow becoming
laminar or turbulent. Fluid with higher viscosity is easier to achieve a turbulent flow condition. The viscosity of fluid is also
dependent on the temperature.

3.2 Laminar Flow

Laminar flow denoted a steady flow condition where all streamlines follow parallel paths, there being no interaction (mixing)
between shear planes. Under this condition the dye observed will remain as a solid, straight and easily identifiable component
of flow.

3.3 Transitional Flow

Transitional flow is a mixture of laminar and turbulent flow with turbulence in the center of the pipe, and laminar flow near the
edges. Each of these flows behaves in different manners in terms of their frictional energy loss while flowing, and have
different equations that predict their behavior.

3.4 Turbulent Flow

Turbulent flow denotes an unsteady flow condition where streamlines interact causing shear plane collapse and mixing of the
fluid. In this condition the dye observed will become disperse in the water and mix with the water. The observed dye will not be
identifiable at this point.
 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:

4.0 EQUIPMENTS & MATERIALS

Figure 1: Unit Assembly of Osborne Reynolds Demonstration

1. Dye reservoir 5. Observation tube

2. Dye control valve, V4 6. Overflow valve, V3
3. Dye injector 7. Water inlet valve, V1
4. Head tank 8. Bell mouth
9. Water outlet valve, V2

The Osborne Reynolds Demonstration apparatus is equipped with a visualization tube for students to observe the flow
condition. The rocks inside the stilling tank are to calm the inflow water so that there will not be any turbulence to interfere with
the experiment. The water inlet / outlet valve and dye injector are utilized to generate the required flow.
 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:

5.0 PROCEDURES

5.1 Experiment A

1. Lower the dye injector until it is seen in the glass tube.

2. Open the inlet valve, V1 and allow water to enter stilling tank.
3. Ensure a small overflow spillage through the over flow tube to maintain a constant level.
4. Allow water to settle for a few minutes.
5. Let water flow through the visualizing tube.
6. Slowly adjust the dye control valve, V4 until a slow flow with dye injection is achieved.
7. Regulate the water inlet valve, V1 and outlet valve, V2 until a straight identifiable dye line is achieved. The flow will be
laminar.
8. Measure the flow rate at the outlet valve, V2 using volumetric method.
9. Repeat the experiment by regulating water inlet valve, V1 and outlet valve, V2 to produce transitional and turbulent flow.

5.2 Experiment B

1. Follow steps 1 to 6 of Experiment A.

2. By repeating the procedures to create a laminar flow, slowly increase the flow rate until the laminar flow produce small
disturbance or eddies. This will be lower critical velocity.
3. Measure the flow rate at the outlet valve, V2 using volumetric result.
4. Repeat the experiment by first introducing a turbulent flow and slowly decrease flow rate till the flow become transitional.
This will be upper critical velocity.
 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:

6.0 RESULTS & CALCULATION

Reynolds number Re (non-dimensional)

Friction Factor λ (non-dimensional)
Kinematics viscosity v mm2/sec
Pipe diameter D mm
Mean velocity U mm/sec
Higher Critical velocity Ucrit mm/sec
Lower Critical velocity Ucrit mm/sec
Flow rate Q L/s

Volume (L) Time (s) Flow rate, Q (L/s) Flow rate, Q (m3/s) Reynolds Number

If Re < 2100 is laminar flow

If 2100 < Re < 4000 is transitional flow
If Re > 4000 is turbulent flow

Kinematics viscosity for 25°C water = 0.89 x 10-6 m/s

Mean Velocity, U  Glass T ubeDiameter,D

Re 
Kinematic Viscosity, V

UD
Thus, Re 
V

QD
U Glass tube diameter (D) = 0.0156 m, Area (A) = 1.91 x 10-4 m2
AV

QD
Thus, Re 
AV

5.24476 10-6  0.0156

For laminar flow, Re   481.3
1.91 10- 4  0.89  10-6
 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:

Typical Visual Test Result

Laminar Flow Transitional Flow

Turbulent Flow
 FACULTY: ENGINEERING EDITION:
TECHNOLOGY
LABORATORY: FLUID
REVISION NO:
MECHANICS

EFFECTIVE DATE: 1/3/2014

EXPERIMENT: OSBORNE
REYNOLDS DEMONSTRATION AMENDMENT
DATE:

7.0 DATA ANALYSIS

8.0 DISCUSSIONS & CONCLUSION

Approved by / Disahkan oleh :

Prepared by / Disahkan oleh:

Signature / Tandatangan :
Signature/Tandatangan:
Name / Nama : PM. DR. ANGZZAS SARI
Name/Nama: DR. NOR FAIZAH BINTI RAZALI
BINTI MOHD KASSIM
Date/Tarikh :
Date / Tarikh :