Engineering Commons^™

Induced Drag Laboratory Curriculum With Variable Aspect Ratio Wing, Alexander Milligan, Elizabeth Plyler

Williams Honors College, Honors Research Projects

A laboratory curriculum for undergraduate students at The University of Akron enrolled in 4600:413 Introduction to Aerodynamics was created to allow students a hands-on opportunity to study the basic fundamentals of aerodynamically induced drag. To accomplish this, a 3D printed wing was created with variable aspect ratio. This wing is to be utilized in the laboratory experiment in The University of Akron subsonic wind tunnel to generate data on lift on drag at different airspeeds, angles of attack, and aspect ratios. The laboratory curriculum provides basic theory applicable to the wind tunnel experiments as well as question prompts and data …

Lifting-Line Predictions For Life And Twist Distributions To Minimize Induced Drag In Ground Effect, Kyler Church

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The elliptic lift distribution produces the minimum induced drag for a given wingspan and desired lift outside of ground effect. This distribution can be generated on any wing by using geometric and/or aerodynamic twist. However, in ground effect, the elliptic lift distribution is not necessarily that which minimizes induced drag. The present work uses a modern numerical lifting-line algorithm to evaluate how the optimum lift distribution varies as a function of height above ground. The algorithm is also used to obtain the twist distributions that should be applied to wings of varying aspect ratios and taper ratios to produce the …

Minimum Induced Drag For Tapered Wings Including Structural Constraints, Jeffrey D. Taylor, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

LIFTING-LINE theory [1,2] is the foundation for much of our understanding of finite-wing aerodynamics. Solutions based on lifting-line theory are widely accepted and have been shown to be in good agreement with CFD [3-10]. From Prandtl’s analytic solution to the classical lifting-line equation [1,2], the wing section-lift distribution can be expressed as a Fourier series of the form [11]

bL^~ (θ)/L = (4/π)[sin(θ) + Σ^∞_n-2 B_nsin(nθ)]; θ = cos^-1(-2z/b) (1)

where b is the wingspan, L^~ is the local wing section lift, L is the total wing lift, z is the spanwise …

A Study Of The Standard Cirrus Wing Lift Distribution Versus Bell Shaped Lift Distribution, William H. Bergman

Master's Theses

This thesis discusses a comparison of the differences in aerodynamic performance of wings designed with elliptical and bell-shaped lift distributions. The method uses a Standard Cirrus sailplane wing with a lift distribution associated with the induced drag benefits of an elliptical distribution (span efficiency = 0.96) as the basis of comparison. The Standard Cirrus is a standard class sailplane with 15-meter wingspan that was designed by Schempp-Hirth in 1969. This sailplane wing was modeled and analyzed in XFLR5, then validated against existing wind tunnel airfoil data, and Standard Cirrus flight test data. The root bending moment of the baseline wing …

Literature Review: Biomimetic And Conventional Aircraft Wing Tips, Naseeb Ahmed Siddiqui, Waqar Asrar, Erwin Sulaeman

International Journal of Aviation, Aeronautics, and Aerospace

This paper is an attempt to summarize the effect of wing tip devices employed by birds, as well as aeronautical engineers in the past to improve the performance characteristics of aircraft. The focus is on reduction of the induced drag or drag due to lift also known as inviscid drag. This paper will provide an insight on both biomimetic and conventional wing tip approaches to reduce the induced drag. Prior analysis and experiments on the aerodynamics of airplane performance due to both these separate studies have been discussed. The needs of the industry and their past inventions have been described …

Lifting-Line Predictions For Induced Drag And Lift In Ground Effect, W. F. Phillips, Doug F. Hunsaker

Mechanical and Aerospace Engineering Faculty Publications

Closed-form relations are presented for estimating ratios of the induced-drag and lift coefficients acting on a wing in ground effect to those acting on the same wing outside the influence of ground effect. The closed-form relations for these ground-effect influence ratios were developed by correlating results obtained from numerical solutions to Prandtl’s lifting-line theory. Results show that these influence ratios are not unique functions of the ratio of wing height to wingspan, as is sometimes suggested in the literature. These ground-effect influence ratios also depend on the wing planform, aspect ratio, and lift coefficient.

Lifting-Line Predictions For Induced Drag And Lift In Ground Effect, W. F. Phillips, Doug F. Hunsaker

Mechanical and Aerospace Engineering Faculty Publications

Closed-form relations are presented for estimating ratios of the induced-drag and lift coefficients acting on a wing in ground effect to those acting on the same wing outside the influence of ground effect. The closed-form relations for these ground-effect influence ratios were developed by correlating results obtained from numerical solutions to Prandtl's lifting-line theory. Results show that these influence ratios are not unique functions of the ratio of wing height to wingspan, as is sometimes suggested in the literature. These ground-effect influence ratios also depend on the wing planform, aspect ratio, and lift coefficient.