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I/We* have read this thesis and from my/our* opinion this thesis

is sufficient in aspects of scope and quality for awarding Bachelor of Mechanical Engineering (Design & Innovation)

Signature : ………...

Supervisor Name : Mr. Ahmad Rivai

Date : ………...

Signature : ………...

Supervisor II Name : Mdm. Ernie Binti Mat Tokit

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AERODYNAMIC PERFORMANCE OF AIRCRAFT PROPELLER

MOHD MUHYIDDIN BIN MUSTAFA

This report is presented in

partial fulfillment of the requirements for the

Bachelor of Mechanical Engineering (Design & Innovation)

Faculty of Mechanical Engineering Universiti Teknikal Malaysia Melaka

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I hereby declare that this report entitled Aerodynamics Performance of Aircraft Propeller” is the result of my own research except as cited in the references.

Signature : ………...

Author’s Name : Mohd Muhyiddin Bin Mustafa

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This thesis is dedicated to my parents, Siti Fatimah Binti Salleh and Mustafa Bin Ibrahim, my brothers, sisters, Noor Masnira Binti Muhammed Salleh and other

family members who provide a loving, caring, encouraging, and supportive atmosphere. These are characteristic that contribute to the environment that is

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ACKNOWLEDGEMENTS

Alhamdulillah and Thank to Allah S.W.T. with all gracious and merciful for giving me strength and ability to accomplish this project research successfully. I would like to express my gratitude to all those who gave me the possibility to complete this thesis. I am deeply indebted to my supervisor Mr. Ahmad Bin Rivai whose help, stimulating suggestions, encouragement and guidance helped me in all the time of research for and writing of this thesis.

I owe my deepest gratitude to Mr. Yehia Abdel Monem Ahmed Eldrainy, Department of Mechanical Power Engineering, Faculty of Engineering, Alexandria University (Egypt), PHD Student and Research Assistant in Gas Turbine Combustion, Department of Aeronautical Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, UTM (Malaysia). His support at all time encourage me in finishing this project.

I acknowledge the Assoc. Prof. Ir. Dr. Shuhaimi Mansor, Head of Aeronautics Laboratory, Assoc. Prof Dr. Tholudin Hj. Mat Lazim and Mr. Abdul Basid Abd. Rahman, Laboratory Engineer, Aeronautical Engineering Laboratory, Universiti Teknologi Malaysia for their kind guidance and technical support for this project.

I also would like to thanks to Mr. Shafizal Bin Mat, Head of Design & Innovation Department, Faculty of Mechanical Engineering as well as to all lectures of Faculty of Mechanical Engineering for all their assistances.

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ABSTRACT

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ABSTRAK

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CONTENTS

CHAPTER SUBJECT PAGE

DECLARATION ii

DEDICATION iii

ACKNOWLEDGEMENT iv

ABSTRACT v

ABSTRAK vi

CONTENTS vii

LIST OF TABLES xii

LIST OF FIGURES xiv

LIST OF FORMULATIONS xvi

LIST OF ABBREVIATIONS LIST OF SYMBOLS

xvii xviii

CHAPTER I INTRODUCTION

1.1 Project Background 1.2 Problem Statement 1.3 Objectives

1.4 Scope of project 1.5 Summary

1 2 2 3 3

CHAPTER II LITERATURE REVIEW

2.1 Introduction

2.2 Introduction to Propeller

2.2.1 Historical Development of Propeller Theory

4 5

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viii

CHAPTER SUBJECT PAGE

2.2.2 Airfoil Geometry Parameters 2.2.3 Propeller Airfoil Design

2.2.4 Airfoil Terms 2.3 NACA Airfoil Series 2.4 Concept of Aerodynamics

2.4.1 Aerodynamic Forces and Moments

2.4.1.1 Definition of Lift 2.4.1.2 Definition of Drag

2.4.2 Resultant Aerodynamic Forces on Propeller

2.4.3 Definition of Stall

2.5 Aerodynamic Characteristic of Propeller (Propeller Blade Analysis)

2.5.1 Downwash Angle, εb 2.5.2 Section Thrust and

Circumferential Force 2.5.3 Total Relative Airspeed 2.5.4 Axial and Circumferential

Component of Induced Velocity 2.5.5 Section Lift and Drag

2.5.6 Lift Across Span

2.5.7 Propeller Airfoil Requirement 2.6 Propeller Analysis Method

2.7 Computational Fluid Dynamic

2.7.1 Development of Computational Fluid Dynamic

2.7.2 CFD Simulation Software(Fluent) 2.7.3 CFD Process

2.7.4 CFD Simulation Procedures 2.7.5 Defining a Boundary Condition

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ix CHAPTER CHAPTER III SUBJECT METHODOLOGY PAGE

3.1 Introduction 3.2 Project Overview 3.3 Methodology

3.3.1 Propeller Model Xoar 32 x 20 (Pusher)

3.4 Analytical Methods

3.4.1 NACA 2412 Airfoil 3.4.2 Results

3.5 CFD Simulation

3.5.1 Fluent CFD Simulation Methodology

3.5.2 Creating Model and Domain 3.5.3 Solution Procedure Flow

3.5.4 Spalart Allmaras Turbulence Model

3.5.5 Flow Domain

3.5.6 Meshing and Size Function 3.5.7 Boundary Condition 3.6 Validation

3.6.1 Experimental Data 3.6.2 NACA0012 Geometry 3.6.3 Validation Model 3.6.4 CFD Result

3.6.5 Comparison of Simulation and Experiment Data 35 35 36 36 37 37 40 49 49 50 51 52 53 53 54 55 55 55 58 59 60

CHAPTER IV RESULTS

4.1 Computational Fluid Dynamic

Simulation (Model and Domain) 4.1.1 Grid Settings

4.1.2 General Simulation Parameter

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x

CHAPTER SUBJECT PAGE

4.2 Computational Fluid Dynamic Simulation Results

4.2.1 Total Force and Coefficient 4.2.1.1 Simulation 1 4.2.1.2 Simulation 2 4.2.1.3 Simulation 3 4.2.1.4 Simulation 4 4.2.1.5 Simulation 5 4.2.1.6 Simulation 6 4.2.2 Pressure Contours

4.2.3 Velocity Magnitude and Vector 4.2.4 Behaviors of Velocity Vector at

Different Propeller Section and Relative Airspeed

4.2.5 Behaviors of Total Pressure at Different Propeller Section and Relative Airspeed 64 64 64 65 65 66 66 67 67 70 72 74

CHAPTER V ANALYSIS AND DISCUSSION

5.1 Propeller Aerodynamic Performance 5.1.1 Lift and Drag Forces

5.1.2 Lift and Drag Coefficient 5.1.3 Lift/Drag Ratio

78 78 79 80 5.2 Aerodynamic Load Distribution on

Propeller

5.2.1 Pressure Distribution on the Blades

5.2.2 Lift Distribution on the Blade 5.3 Comparison of Analytical and

Simulation Result

81

81 81

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CHAPTER SUBJECT PAGE

CHAPTER VI CONCLUSION AND RECOMMENDATION

6.1 Conclusion 6.2 Recommendation

REFERENCES BIBLIOGRAPHY APPENDICES

83 84

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xii

LIST OF TABLES

NO. TITLE PAGE

2.1 NACA Airfoils Series 12

3.1 Xoar 32 x 20 Geometry 36

3.2 2-D Panel Method Solution Test Parameters 38

3.3 Coefficient of Lift and Drag 39

3.4 Variation of Section Lift Force, to Relative Airspeed, 41 3.5 Variation of Section Drag Force, to Relative Airspeed, 41 3.6 Theoretical Result for Lift force across the propeller span for

10m/s relative airspeed at eleven sections 42

3.7 Theoretical Result for Lift force across the propeller span for

20m/s relative airspeed at eleven sections 43

3.8 Theoretical Result for Lift force across the propeller span for

30m/s relative airspeed at eleven sections 44

3.9 Theoretical Result for Lift force across the propeller span for

40m/s relative airspeed at eleven sections 45

3.10 Theoretical Result for Lift force across the propeller span for

50m/s relative airspeed at eleven sections 46

3.11 Theoretical Result for Lift force across the propeller span for

60m/s relative airspeed at eleven sections 47

3.12 Result of Theoretical calculation for Lift Force across Span at

Different Relative Airspeed 49

3.13 Experimental Data of Lift and Drag Coefficient 55

3.14 Detail Coordinate of the NACA0012 Geometry 57

3.15 Fluent Simulation Result 59

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xiii

NO. TITLE PAGE

4.1 General Simulation Parameters - Models 63

4.2 General Simulation Parameters – Zones 63

4.3 General Simulation Parameters – Air Properties 64

4.4 Inlet Parameter for Simulation 1 64

4.5 Result for Simulation 1 64

4.6 Inlet Parameter for Simulation 2 65

4.7 Result for Simulation 2 65

4.8 Inlet Parameter for Simulation 3 65

4.9 Result for Simulation 3 65

4.10 Inlet Parameter for Simulation 4 66

4.11 Result for Simulation 4 66

4.12 Inlet Parameter for Simulation 5 66

4.13 Result for Simulation 5 66

4.14 Inlet Parameter for Simulation 6 67

4.15 Result for Simulation 6 67

4.16 Variation of Total Pressure at Different Relative Airspeed 69 4.17 Variation of Velocity Magnitude at Different Relative Airspeed 70 4.18 Behaviors of Velocity Vector at different Section and Airspeed 72 4.19 Behaviors of Total Pressure at different Section and Airspeed 74

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LIST OF FIGURES

NO. TITLE PAGE

2.1 Propeller Construction 7

2.2 Propeller Lay-Out 8

2.3 General Propeller Terms 9

2.4 Propeller Blade Angle 10

2.5 Static Pressure Distribution 15

2.6 Shear Stress Distribution 15

2.7 Resultant aerodynamic force and the components into which it splits 17

2.8 Stall Conditions 18

2.9 Section force and velocities acting on a rotating propeller blade 19

2.10 Elliptical Lift Distribution 23

3.1 Xoar 32 x 20 Propeller 36

3.2 NACA Airfoil Section Generator 37

3.3 2-D Panel Method Solution Software 39

3.4 Graph for Lift force across the propeller span for 10m/s relative airspeed 42 3.5 Graph for Lift force across the propeller span for 20m/s relative airspeed 43 3.6 Graph for Lift force across the propeller span for 30m/s relative airspeed 44 3.7 Graph for Lift force across the propeller span for 40m/s relative airspeed 45 3.8 Graph for Lift force across the propeller span for 50m/s relative airspeed 46 3.9 Graph for Lift force across the propeller span for 60m/s relative airspeed 47

3.10 Ellipse Nomenclature 48

3.11 CFD Simulation Flow Chart 50

3.12 Solution Procedure Flow 51

3.13 NACA 0012 Airfoil 58

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xv

NO. TITLE PAGE

3.15 Velocity Vector for SIM 2 60

4.1 Simulation Flow Domain 62

4.2 Propeller Wall 62

4.3 Propeller in Flow Domain 63

4.4 Example: Contours of Total Pressure for Simulation 1 67 4.5 Example: Contours of Total Pressure for Simulation 1 (Blade Back) 68 4.6 Example: Contours of Total Pressure for Simulation 1 (Blade Face) 68 4.7 Graph of Total Pressure Acting on Propeller

at Different Relative Airspeed 69

4.8 Example: Velocity Vector for Simulation 1 70

4.9 Graph of Velocity Magnitude Acting at Propeller Wall

at Different Relative Airspeed 71

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LIST OF FORMULATIONS

NO. TITLE PAGE

(1) Lift, Normal, and Axial Force Equation 17

(2) Drag, Normal, and Axial Force Equation 17

(3) Total Downwash Angle 20

(4) Section Thrust 20

(5) Circumferential Force 20

(6a) Total Relative Airspeed 21

(6b) Total Relative Airspeed 21

(7) Induced Velocity 21

(8) Axial Component of Induced Velocity 22

(9) Circumferential Component of Induced Velocity 22

(10) Downwash Angle 22

(11) Advance Angle 22

(12) Induced Angle 22

(13) Section lift at radius, r 22

(14) Local Section Drag at radius, r 23

(15) Lift across Span 23

(16) Reynolds Number 38

(17) Local Section Lift 40

(18) Local Section Drag 40

(19) Lift force Using the Elliptical Lift Distribution Approach 41

(20a) Ellipse area 48

(20b) Ellipse area 48

(20c) Modified Ellipse area 48

(21a) Formula for the NACA 00XX Shape 55

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LIST OF ABBREVIATIONS

A - Axial Force

CAD - Computer-aided Design CAE Computer-aided Engineering

CATIA - Computer Aided Three-Dimensional Interactive Application CFD - Computational Fluid Dynamic

CMM - Coordinate Measuring Machine

CTRM - Composites Technology Research Malaysia

D - Drag Force

GUI - Graphical User Interface

k - Number of Blade

L - Lift Force

M - Moment

N - Normal Force

NACA - National Advisory Committee for Aeronautics

r - Radial Distance

R - Resultant Aerodynamic Force/Freestream Velocity RANS - Reynolds-averaged Navier–Stokes Equations TUAV - Tactical Unmanned Aerial Vehicle

SIM - Simulation

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LIST OF SYMBOLS

α - Angle of Attack

β - Aerodynamic Pitch Angle

εb - Total Downwash Angle

ε∞ - Propeller’s Forward Motion Vb - Total Relative Airspeed V∞ - Relative Air Velocity

ω - Angular Velocity

cb - Local Section Chord Length

Cd - Drag coefficient

Cl - Lift coefficient

Re - Reynolds Number

ρ - Density

μ - Viscosity

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CHAPTER I

INTRODUCTION

1.1 Project Background

An Aircraft Propeller is one of the most common important parts in the aircraft. It is an airfoil section designed to generate an aerodynamic force. The propeller force provides thrust to push the aircraft through the air. Thrust is the component of the aerodynamic force that is parallel to the axis of rotation. A propeller achieves a specified level of thrust by giving a relatively small acceleration to a relatively large mass of air.

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In order to analyze the aerodynamic performance of the propeller, Computational Fluid Dynamic (CFD) software is used to simulate the fluid flow over a body to solve and analyze the aerodynamic properties of a body. While, analytical approach will be used to compare the result gather from CFD simulation.

1.2 Problem Statement

Aircraft propeller evaluation in terms of aerodynamic performance is a critical aspect in designing an aircraft propeller. Propeller used to generate thrust that pushes the aircraft through the air. Thus, it is important to determine the aerodynamic performance and the aerodynamic load distribution over the propeller body. Since the airframe of an aircraft is induced by the drag on the air, the propeller needs to provide enough thrust to overcome the drag. There are several tools and method that can be used to analyze the aerodynamic performance of an aircraft propeller such as the Computational Fluid Dynamic simulation.

1.3 Objectives

The objectives of this thesis are:

a) To determine aerodynamic performance of an aircraft propeller especially Lift and Drag forces using analytical and CFD approaches.

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1.4 Scope of Project

The scope of the project is focused on the aerodynamic performance of aircraft propeller. Research is made to understand the aircraft propeller in general. Computational Fluid Dynamics (CFD) software is used to analyze and simulate the propeller in terms of aerodynamic performance and aerodynamic load distribution. The result of manual calculation and CFD software is compared.

1.5 Summary

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CHAPTER II

LITERATURE REVIEW

2.1 Introduction

This literature review explores the dominant themes includes study and research of published materials like journals, thesis, case study, technical document, and online library. Generally, the purpose of a review is to analyze critical segment of a published body of knowledge through summary, classification and comparison of prior research studies, reviews of literature, and theoretical articles.

This chapter describes topics that related to propeller aerodynamics such as propeller theory, propeller geometry and parameters, aerodynamics forces and Computational Fluid Dynamic. Emphasize is more on aerodynamics force on the propeller blade and also the computational fluid dynamic approach and simulation.

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2.2 Introduction to Propeller

The airplane propeller consists of two or more blades and a central hub to which the blades are attached. Each blade of an airplane propeller is essentially a rotating wing. As a result of their construction, the propeller blades are like airfoils and produce forces that create the thrust to pull, or push, the airplane through the air.

The power needed is supplied by the engine to rotate the propeller blades. The engine rotates the airfoils of the blades through the air at high speeds, and the propeller transforms the rotary power of the engine into forward thrust. As the air flows past the propeller, the pressure on one side of propeller is less than that on the other. As in a wing, this produces a reaction force in the direction of the lesser pressure. Propeller is mounted in a vertical plane, the area of lower pressure is in front of the propeller. Thus the thrust force is created in a forward direction.

Drag force that oppose the forward motion of an aircraft will be created as it moving through the air. Consequently, if an aircraft fly, there must be a force applied to it that is equal to the drag force, but acting in opposite direction. This force is called as the "thrust."

2.2.1 Historical Development of Propeller Theory

Development of a rational propeller theory begins with the work of Rankine and Froude with their interest in moving propulsion, but the fundamental principle is the same for water and air. They developed the fundamental momentum relation governing a propulsive device in fluid medium. (Wald Q. R, 2006)

References

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