Design and Analysis a New Spoiler for Ump Rev Using Cfd
Total Page：16
File Type：pdf, Size：1020Kb
DESIGN AND ANALYSIS A NEW SPOILER FOR UMP REV USING CFD MUHAMMAD NAJMUDIN BIN MOHD TAIB A report is submitted in partial fulfillment of the requirements for the award of the degree of Bachelor of Mechanical Engineering Faculty of Mechanical Engineering Universiti Malaysia Pahang. - - :i NOVEMBER 2007 vi ABSTRACT This thesis presents the design and develops new rear spoilers to overcome a drag force that is created because of low pressure zone at the rear hack. With the new design of rear spoiler for the Proton iswara Hybrid Electrical Vehicle (BV) UMP, the performance of the car had increased from the aspect of acceleration and also from the aspect of handling of the car, the controlled speed of this research is from 80 km/hr to 110 km/hr. The design of rear spoiler is based on the type of the car used, therefore aerodynamic shape of the body and the point of the rear spoiler is important in this research. In this research 2 spoilers have been choosing that are squareback and fastback rear spoilers. According to that reason, low pressure zone will be annihilated slowly if one of the rear spoilers is put at the rear back of the car. Refer to data testing obtained, using squareback spoiler will reduce more low pressure zone than using fastback spoiler. Based on the analysis, the suitable place to mount the rear spoiler is at the point where squareback spoiler is mounted and it synchronized with the shape of the Proton Iswara HEy. It will give additional information to the performance car researcher to continue on this research thoroughly about the effect of spoiler on any HEY car and eventually to Malaysia's first HEV race car. In the future, this factor will give benefit to the Malaysia car developer especially HEY car developer. vii ABSTRAK Tesis mi telah merekabentuk spoiler belakang barn bagi mengatasi masalah kewujudan daya tarikan yang wujud di zon belakang kereta. Dengan adanya spoiler belakang mi juga prestasi kereta Proton Iswara jenis Hybrid Electrical Vehicle (HEV) UMP mi akan rneningkat dari segi kelajuan dan pemanduan semasa berada di dalam kelajuan 80 km/sejjarn hingga 1110 krn!sejarn. Rekabentuk spoiler belakang mi berpandukan jenis kereta dan faktor-faktor seperti bentuk yang aerodinamik dan kedudukan spoiler belakang itu. Di dalam kajian mi dua buah spoiler belakang telah dibentuk iaitu jenis 'squareback' dan jenis 'fastback'. Menurut kajian mi, dengan kehadiran salah satu spoiler belakang mi masalah kewujudan zon tekanan tinggi di belakang kereta dapat dikurangkan dengan banyaknya. Daripada data ujikaji barn mi, dngan kehadiran spoiler jenis 'squareback' dapat mengurangkan zon tekanan tinggi lebih banyak berbanding spoiler jenis 'fastback'. Berpandu kepada analisa, kedudukan spoiler yang strategik adalah pada kedudukan spoiler jenis 'squareback' berbanding spoiler jenis 'fastback'. mi adalah disebabkan rekabentuk kereta Proton Iswara HEy yang sesuai dengan spoiler jenis 'squareback' mi. mi memberikan satu isyarat kepada para pengkaji berkaitan prestasi kereta untuk nieneruskan kajian dengan lebih mendalam terhadap kesan spoiler belakang pada kereta jenis HEY di Malaysia seterusnya untuk kereta lumba jenis HEY keluaran Malaysia. Semoga pada masa akan datang, faktor mi akan mendatangkan nilai yang mendalam terhadap bidang kenderaan terutamanya j enis HEV. vi" TABLE OF CONTENTS CHAPTER TITLE PAGE SUPERVISOR DECLARATION STUDENT DECLARATION DEDICATION iv ACKNOWLEDGEMENT v ABSTRACT vi ABSTRAK vii TABLE OF CONTENTS vii LIST OF FIGURES xi LIST OF TABLES xiii LIST OF SYMBOLS xiv LIST OF APPENDICES xv 1 INTRODUCTION 1.1 Spoiler I 1.2 Problem Statement 3 1.3 Project Objectives 4 1.4 Project Scopes 4 2 LITERATURE REVIEW 2.1 Introduction 5 2.2 Aerodynamics 7 x 2.2.1 Definition 7 2.2.2 Classes of Aerodynamic Problem 7 2.2.3 The Dynamic of Airflow and 8 Its Effects on Automobiles 2.2.4 Automotive Aerodynamics 8 2.3 Flow Separation through a Road Vehicle 9 2.3.1 Introduction 9 2.3.2 Flow Separation Process 9 2.3.3 External Flow 10 2.3.4 Boundary Layer Development 12 2.3.5 Laminar & Turbulent Flows 13 2.3.6 Drag Coefficient 14 2.4 Pressure Difference 14 2.5 Rear Spoiler 15 2.5.1 Introduction 15 2.5.2 Effect of Rear Spoiler 16 2.6 Hybrid Electrical Vehicle (HEY) 18 2.6.1 Development of HEV 18 2.6.2 Types of HEV 19 2.6.3 Battery Requirements for HEY 20 2.7 Computational Fluid Dynamics (CFD) 23 2.7.1 Introduction of CFD 23 2.7.2 COSMOS Floworks (Introduction) 23 2.7.3 Computational Domain 24 2.7.4 Meshing 25 2.7.5 Analysis Type 26 3 METHODOLOGY 3.1 Introduction 28 3.2 Project Methodology 28 3.3 Verify the FYP title given with supervisor 31 3.4 Searching information for literature review 31 x 3.4.1 Book and magazine 31 3.4.2 Related journal 32 3.4.3 Internet source 32 3.4.4 Discuss with supervisor and lectures 32 3.5 Measure the dimension of HEV Proton Iswara 33 3.6 3D Solid Modeling 34 3.6.1 HEV Proton Iswara's Body 34 3D Solid Modeling 3.6.2 Rear Spoiler Design 35 3D Solid Modeling 3.7 Air Flow Analysis 37 3.7.1 Simulation Air Flow Analysis 37 3.8 Data Gathered from Results 38 4 RESULTS AND DISCUSSION 4.1 The Information Regarding 39 The Result Obtained 4.2 The Effect of Fastback and Squareback 40 Rear Spoiler on REV Proton Iswara 4.2.1 Results View atllOkmjhr 40 4.2.2 Data table and graph at 110 km/hr 43 4.2.2.1 Analyze for the Side View 43 4.2.2.2 Analyze for the Rear View 46 5 CONCLUSION 5.1 Conclusion 50 5.2 Recommendations for Future Works 51 REFFERENCES 53 APPENDIX 54 xl LIST OF FIGURES FIGURE NO. TITLE PAGE I.I. The Rear Spoiler I 1.2 Aerodynamic flow around the car 2 2.1 Overview diagram for Literature Review 6 2.2 Flow separation process 10 2.3 Boundary layer 11 2.4 Flow around a vehicle (schematic). 11 2.5 Flow through a plate 12 2.6 Velocity boundary layer development on a flat plate 13 2.8 Pressure Differences at Car 15 2.9 Fastback Rear Spoiler 15 2.10 Two-dimensional flap as simulation model 16 for a rear spoiler 2.11 Drag lift pollars for different rear 17 spoiler arrangements 2.12 Pressure increase at the rear of a vehicle due to 17 a rear spoiler 2.13 Isobars on a fastback, with and without spoiler 18 2.14 11EV Drives Train Examples. 20 2.15 Examples for battery configurations for different 20 EV and 11EV drive trains xli 2.17 Power profile of a 1130 kg car onNEDC 22 2.20 External Flows on COSMOS Floworks 26 3.1 Flow chart of project methodology 30 3.2 Proton lswara full models with dimension 35 3.3 Squareback full model and dimension 36 3.4 Fastback full model and dimension 36 4.1 Car without spoiler (Side view) 40 4.2 Car with fastback rear spoiler (Side View) 40 4.3 Car with squareback rear spoiler (Side View) 41 4.4 Car without spoiler (Rear view) 41 4.5 Car with fastback rear spoiler (Rear View) 42 4.6 Car with squareback rear spoiler (Rear View) 42 4.10 Car without Spoiler vs. With Fastback Spoiler 44 4.11 Car without Spoiler vs. With Squareback Spoiler 45 4.12 Different Graph for car with and without Spoiler 45 4.16 Car without Spoiler vs. With Fastback Spoiler 47 4.17 Car without Spoiler vs. With Squareback Spoiler 48 4.18 Different Graph for car with and without Spoiler 48 xlii LIST OF TABLES FIGURE NO. TITLE PAGE 2.7 Drag Coefficient for Different Bodies 14 (Cd,c = D/qk Subcritical Flow) 2.16 PNGV definition/requirements of batteries for HEy 21 2.18 Cell size for 200-300 V, 1 kW h power 22 assist HEV battery 2.19 HEV battery requirements 23 3.1 Proton Iswara Specifications from Proton 33 Sdn. Bhd. web 4.7 Car without Rear Spoiler 43 4.8 Car with Fastback Spoiler 43 4.9 Car with Squareback Spoiler 44 4.13 Car without Rear Spoiler 46 4.14 Car with Fastback Spoiler 47 4.15 Car with Squareback Spoiler 47 xiv LIST OF SYMBOLS Cd Drag Coefficient V Velocity Re Reynold Number V Viscosity Shear Stress U Gradient 'rs Surface Shear Stress FD Surface Drag Force S Cross Sectional Area w Watt V Volt xv LIST OF APPENDICES APPENDIX TITLE PAGE A Solid Work design 54 B Results from the simulation 60 C Point Parameters 62 CHAPTER 1 INTRODUCTION 1.1 Spoiler A spoiler is an aerodynamic device attached to an automobile whose intended design function is to 'spoil' unfavorable air movement across a body , of a car in motion. This can result in improved vehicle stability by decreasing lift or decreasing drag that may cause unpredictable handling-in a-car at high speed. Spoilers are often fitted to race and high-performance sports cars, although they have become common on passenger vehicles, as well. Some spoilers are added to cars primarily for styling purposes and have either :littie ae'rodyhimi& ,'bene'fiti or even make the aerodynamics, worse. Figure 1.1: The rear spoiler 2 Spoilers are often incorrectly confused with, or even used interchangeably with wings. Automotive wings are devices whose intended design is to actually generate downforce as air passes around them, not simply disrupt existing airflow patterns. Spoilers generally work by disrupting the airflow going over a car.