Question

17. [12 pt] Taking MEEN 3700 has made you slightly crazy and you have therefore, decided to enter the Redbull Flugtag competition this summer in Louisville. The goal is to develop a human powered flying machine capable of the longest flight possible from a tower into a river (see figure). Besides planning to use a prodigious amount of duct tape, you have also decidesd to put your fluid dynamics knowledge to good use and develop a basic dynamics model. The machine's mass M is set by the competition rules as is the max- imum wing span D. Using your chosen materials (duct tape and cardboard) you estimate a maximum wing chord length of C and thickness (. Based on the foot speed of your most athletic friend, you estimate an initial horizontal velocity U Part A) Derive an equation for the time t it will take your flying machine to fall into the river with style assuming it is at terminal vertical velocity Vi when it is released from the platform at height H. Use the density of air and the variables given in the figure with an assumed lift coefficient Ci and the assumption that the appropriate planform area equals the wing area, Part B) Assuming your time from part A is given by t derive an equation for the horizontal distance L your design will travel before gracefully landing in the water. Use the density of air ? and the variables given in the figure with an assumed drag coefficient CD

Answer 1

Solehoy 6 N t 1

lano ClD 뇟 f, vl.CXDXC處 CD CD