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CERTIFICATION OF APPROVAL
Drag Reduction on How to Improve Fuel Consumption of a Vehicle
by
Kamarul Ariffin B Kasnin
A project dissertation submitted to the Mechanical Engineering Programme
Universiti Teknologi PETRONAS in partial fulfilment of the requirement for the
BACHELOR OF ENGINEERING (Hons) (MECHANICAL ENGINEERING) Approved by,
_____________________
(Ir Dr Masri Bin Baharom)
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UNIVERSITI TEKNOLOGI PETRONAS TRONOH, PERAK
NOVEMBER 2010
CERTIFICATION OF ORIGINALITY
This is to certify that I am responsible for the work submitted in this project, that the original work is my own except as specified in the references and acknowledgements, and that the original work contained herein have not been undertaken or done by unspecified sources or persons.
___________________________________________
KAMARUL ARIFFIN KASNIN
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ABSTRACT
Automotive aerodynamics is the study of the aerodynamics of road vehicles. The main concerns of automotive aerodynamics are reducing drag (though drag by wide wheels is dominating most cars), reducing wind noise, minimizing noise emission, and preventing undesired lift forces and other causes of aerodynamic instability at high speeds.
The aim of this project is to provide a study on the aerodynamics profile of a vehicle (Perodua Viva) and ways to reduce drag to improve its fuel consumption. The methods used to reduce the drag are by tapering the rear, covering the wheel wells and also by having a smooth, lowered underbelly. A drag coefficient is a number that indicates the car’s aerodynamics smoothness. A bigger, bulkier car often has higher coefficient of drag. Higher drag coefficient causes the car to do more work when driven. More work done by the engine causes more fuel to be burned. Often we see that for two vehicles with the same engine capacity driven at the same speed, the car having bigger coefficient of drag will consume more fuel.
In order to achieve the lowest fuel consumption as possible, the car will undergo several modifications that will reduce its coefficient of drag, thus reducing the engine’s need for more fuel.
This project is also performed as part of the Perodua Eco Challenge Competition, where institutes of higher learning are given a Perodua Viva each, and they are required to modify them to obtain as little fuel consumption as possible. The team which records the most distance travelled using only a litre of fuel is the winner.
Overall, the project has achieved a reduction of drag of about 22% and the fuel consumption improves from 18.9 km/l to 25.7 km/l.
iv ACKNOWLEDGEMENT
First of all, my deepest gratitude to Allah S.W.T because of His blessing and mercy, I manage to finish the Final Year Research Project. I would like to give my highest appreciation to my project supervisor, Ir. Dr. Masri Baharom for his knowledge, support and guidance for the 30 weeks during this project been conducted.
A highest recognition goes to the Perodua Eco Challenge supervisors, Ir Dr Masri B Baharom and Dr Zainal Ambri Abdul Karim, as well technical assistance from Mr Saifuddin for involving directly or indirectly in the project. I would like to thank all Mechanical Engineering Department technicians their precious guidance, help and encouragements.
Apart from that, I would like to give credits to my colleagues who give excellent cooperation in completing this Final Year Research Project. Not to be forgotten, to my family for their boundless support from the beginning till the end of this project. Lastly, thank you to all parties who participate directly or indirectly in completing this project.
Your contributions are highly appreciated.
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TABLE OF CONTENTS
ABSTRACT ……….…... iii
LIST OF ABBREVIATIONS……….vi
CHAPTER 1: INTRODUCTION …..………....1
1.1 Background of Study ...……….……1
1.2 Problem Statement………....1
1.3 Objectives and Scope of Study ………....2
CHAPTER 2: LITERATURE REVIEW ……….4
CHAPTER 3: METHODOLOGY ………...13
CHAPTER 4: RESULTS AND DISCUSSIONS………..25
CHAPTER 5: CONCLUSION………...40
REFERENCES ………..42
Appendix……….…43
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LIST OF ABBREVIATIONS
Cd Coefficient of Drag CL Coefficient of Lift PEC Perodua Eco Challenge
CFD Computational fluid dynamics AWTE Automotive Wind Tunnel NSMB Navier-Stokes Multi-Block
UTP University of Technology Petronas Cp Coefficient of Pressure
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LIST OF FIGURES/PICTURES
Figure 1: streamlined Maybaches in the 1930’s Figure 2: standard Honda Civic CX
Figure 3: aerodynamic Civic (Aerocivic) Figure 4: concept car by Bentley
Figure 5: a Pagani Zonda undergoing a wind tunnel test Figure 6: a scaled wind tunnel used by nascar
Figure 7: a scale model of a Nascar race vehicle
Figure 8: sample result of a Nascar’s wind tunnel experiment Figure 9: Fuel economy for some cars.
Figure 10: taping strings for tuft test Figure 11: vehicle undergoing tuft test Figure 12: installing diffuser
Figure 13: side air ducts to channel air from front Figure 14: A standard Perodua Viva
Figure 15: UTP PEC’s Modified Perodua Viva Figure 16: UTP PEC’s Perodua Viva (rear view).
Figure 17: a DL2 data logger used in the coast down test.
Figure 18: An example of a wind tunnel graphical user interface and data measurement.
Figure 19: vehicle undergoing coast down test
Figure 20: Track visualization generated from DL2 Data Logger
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LIST OF TABLES
Table 1: Summary of Test Results
Table 2: sample data from coast down test Table 3: Fuel Consumption Test Results
LIST OF GRAPHS/PLOTS
Figure 1: Plot of Speed vs Time for coast down test Figure 2: Drag vs Speed
Figure 3: Power vs Speed
Figure 4: Plot of fuel consumption for different vehicle configurations
