{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

HW13solution

# HW13solution - AAE 334 Fall 2011 Homework 13 Due Friday...

This preview shows pages 1–2. Sign up to view the full content.

AAE 334, Fall 2011, Homework 13 Due Friday, September 30, at the beginning of class. 1. Increasing the aspect ratio of a rectangular wing by increasing span while keeping chord, velocity, density, and lift force constant causes what change induced drag? Show your work. Induced drag coefficient is given by: 1 2 AR C C L Di and thus, induced drag force is given by: 1 2 2 2 AR S q L qS D i or 1 1 1 2 2 2 2 2 b q L S b qS L AR qS L D i or, 2 2 1 1 b q L D i . Thus increasing the span reduces induce drag. Some of you noted that we need to be concerned about changes in the induced drag factor. I didn t intend this step, but yes, it is correct. The rightmost ends of the curves in Figure 5.20 show that 100 AR for rectangular wings. Thus our equation for induced drag becomes,

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}