Lab 2 – Hot Air Balloon Competition

1. Lab 2 – Hot Air Balloon Competition EG1003 Section E2 Date of Experiment: 9/16/11 Date Due: 9/21/11 Tony Tao and Abe Gellis

2. Overview • Experimental Objective • Introduction • Background Information • Materials • Procedure • Data and Observations • Results • Conclusions

3. Experimental Objective • Construct a lighter-than-air construct capable of lifting as much weight as possible, for as long as possible, using minimalist design to reduce costs.

4. Introduction • Ideal lighter-than-air aircraft lifts as effectively as possible at low expense • Improving the design of the aircraft improves its utility in the fields that use it • Experiments with minimal design can lead to new, more affordable solutions and designs here and in other fields

5. Background Information • Lighter-than-air aircraft have existed for over 200 years, pioneered by the Montgolfier brothers • Predominantly used for entertainment, advertising, and a convenient way to work at a high elevation • Varying kinds of aircraft, some using gases lighter than air

6. Background Information • Ideal Gas Law • Heating the air inside a balloon expands the air and lowers density by forcing some out • Upward buoyancy force • Volume of less-dense heated air weighs less than surrounding cool air, is propelled upward • Archimedes’ Principle • Buoyancy force is equal to the amount of air displaced by the balloon

7. Background Information • Test hot air balloon designs by attaching paper clips and holding over a heater • Goal was to design a balloon that floated as long as possible, holding as much weight (in paperclips) as possible, for as little as possible • Judged and compared to other balloons in class to determine the balloon that was the most effective at the best price (Time Afloat) x (Paperclips Carried)Cost of Balloon Materials

8. Materials Used • Some materials had a “cost” attached • Tissue paper (1 sheet) (10¢) • Gluestick (free) • Scissors (free)

9. Procedure • Plan design for aircraft • Obtain/purchase materials • Construct balloon • Attach paperclip(s) • Hold balloon over heater, fill with hot air, then let go and allow balloon to rise • Modify balloon as necessary and perform up to two more trials

10. Data and Observations • Balloon sank immediately after filling • Time spent in air was due to the fact that it fell slowly • Balloon did not cover heater sufficiently • Heater heated air around as well as inside balloon • Outside air was same density as inside, providing no buoyancy • Only one trial conducted • No addition or modification would remedy the fundamental issue

11. Results • Balloon achieved no flight nor buoyancy • Was incapable of lifting any weight • Was cheap • Achieved 6th place in class • Mostly due to cheapness

12. Conclusion • Successful minimal design • 10¢ total cost • …at the expense of functionality • Other designs allowed little or no hot air to escape • Were willing to spend more money in order to create larger, more capable designs • Did not account for size of heater • Only redeeming feature was lightness • Minimalism is important, but should not be first priority