Wing Design

Topics: Wing design, Aerodynamics, Wing Pages: 9 (2771 words) Published: May 7, 2013
Coursework 2: Wing Design|
Module: NG1S208 Professional Practice For Engineers

|
|
2012|
|
|

Foreword

The following document is a research analysis involving the various aspect that make up the design factor of a wing with main focus being on the geometrical perspective of wing design. Each aspect engineers consider when designing a wing will be discussed in detail as well as the effect of certain modifications to the efficiency of aircraft. It can be noted that this is an integrated look at the basic requirements necessary to design an efficient wing.

Foreword2
Nomenclature3
1.0Introduction4
2.0Factors Affecting the design of a wing5
2.1Aspect Ratio4
2.2Wing Sweep……………………………………………………………………………………………………………..6 2.3Taper………………………………………………………………………………………………………………………..8 2.4Twist…………………………………………………………………………………………………………………………8 2.5Dihedral……………………………………………………………………………………………………………………9 3.0Some benefits of Wing Design……………………………………..………………………………………………….10

3.1Wing Flaps………………………………………………………………………………………………………………10
3.2Wing Vertical Location……………………………………………………………………………………………11 4.0Conclusion……………………………………………………………….……………………………………………………..13 5.0References………………………………………………………………………………..…………………………………….14

Nomenclature

Figure [ 1 ] A plan view of a wing
The above diagram illustrates the basic terms used when measuring or describing any wing phenomena. Below is an index to some of the terms: b (wingspan) – this is the overall distance of the wing from tip to tip Leading edge – the wing edge closest to the nose of the aircraft Trailing edge _ the wing edge furthest from the nose of the aircraft Co(Root chord) – The distance between the intersection of the leading edge with the aircraft fuselage centre line and the trailing edge with the fuselage. Ct(Tip chord) – The length of the wing tip

CL – The imaginary line of symmetry of a wing
C (standard mean chord) –representing it as a formula:
c=-ssc dy-ssdy Where y=distance from CL to starboard (right of pilot) tip Sweep Angle (Λ) – the angle measured between the line perpendicular to the centre line extended and the leading edge of the wing. The same angle can be measure at the trailing edge. ΛLE- The sweep angle of the leading edge

ΛTE - The sweep angle of the trailing edge
X-X – A cross section of the wing
Supersonic – speeds that exceed Mach 1
Subsonic-speeds lower than Mach 1
Transonic-speeds ranging from Mach 0.8 to Mach 1.2

1.0Introduction

In order for an aircraft to achieve flight, it must produce enough thrust to overcome its own weight and produce maximum lift while ensuring the least drag possible. An in depth analysis of the various geometrical wing factors that contribute to the lift and drag effects of the wing will now be done. Some main design parameters considered when designing a wing are sweep, aspect ratio, taper and twist. Each aspect will be analysed in detail below

2.0Factors affecting the design of a wing

2.1Aspect Ratio

Aspect ratio (A or AR) – this is a measure of the narrowness of the wing plan form given by
A=bc = =b2bc where b= wingspan, c = chord
Raymer (2006) refers to the Wright brothers as being the first to investigate the phenomena of aspect ratio using a wind tunnel they constructed. In general it was discovered that a long, skinny wing had less drag than short and fat wing. When a wing is under the effects of air, it experiences air flow on its upper and lower surfaces as well as the tips of the wing. This is referred to as three-dimensional flow. Air escaping at the wing tips therefore lowers the amount of air passing over the upper and lower wing surfaces and reduces lift toward the tip. Air at the tip flows in a circular manner, commonly referred to as a vortex (fig 2) and this pushes down the wing and reduces the angle the wing experiences air flow or angle of attack.

Figure [...

References: * Kroes M and Rardon J,(1993), Aircraft Basic Science, seventh edition, United States Of America: Glencoe/McGraw-Hill
* E.L Houghton and P.W Carpenter,(1993), Aerodynamics for Engineering Students, Fourth edition, London: Arnold
* P. Raymer,((2006), Aircraft Design : a conceptual approach, Fourth Edition, United states of America: American institute of aeronautics and astronautics
* Wing taper - http://www.homebuiltairplanes.com/forums/aircraft-design-aerodynamics-new-technology/5461-advantages-tapered-wings.html 15/01/12
* wing sweep images - http://www.google.com/imgres?q=swept+forward+wings&hl=en&safe=active&biw=1304&bih=665&gbv=2&tbm=isch&tbnid=PL88IaaEtzAQKM:&imgrefurl=http://www.desktop.aero/appliedaero/potential3d/fsw.html&docid=dqI4NkLvxr7LxM&imgurl=http://www.desktop.aero/appliedaero/potential3d/images/x29.jpg&w=500&h=339&ei=ik8TT6L4JNTe8QPJqI15&zoom=1&iact=hc&vpx=182&vpy=158&dur=1222&hovh=185&hovw=273&tx=173&ty=66&sig=112213249294559830911&page=1&tbnh=143&tbnw=196&start=0&ndsp=16&ved=1t:429,r:0,s:0
* wing twist images - http://www.centennialofflight.gov/essay/Theories_of_Flight/Reducing_Induced_Drag/TH16G5.htm (accessed 24 01 12)
* effects of drag - http://www.aerospaceweb.org/question/dynamics/q0055.shtml (accessed 27 01)
* c-17 image -http://www.af.mil/information/factsheets/factsheet.asp?id=86