Results/Problems/Adjustments:

Launch Video:


Our cannon did not fire, but instead the base began to melt. There was smoke produced (hard to see in the video), which was actually water vapor rising on the CO2because of the cold weather.

Possible reasons the cannon did not fire:


1. The weather was too cold. Gay Lussac's law states that when the temperature and pressure are directly proportional: when the temperature went down, so did the pressure.

2. The seal on the base of the chamber was not airtight, so the pressure escaped instead of launching the Nerf ball.

3. The ethanol had not vaporized enough to get the initial reaction (launch) we were looking for.

4. The hole in the base of the cannon for the wood splint was not large enough, which would have either a) not let enough oxygen in, or b) not let the wood splint in far enough to ignite the ethanol.



Changes/Ideas For a New Cannon:

1. Instead of cutting up the barrel, adding the lid, and taping it back, adjust the lid to fit inside the barrel so an air-tight seal in the barrel is maintained.

2. Instead of having one hole in the lid, place several smaller ones (maybe using a hole-puncher) so that an even pressure is exerted on the Nerf ball.

3. Find a consistent, warmer temperature and give the ethanol time to turn to gas inside the chamber.

4. Use the hole-puncher to make a hole for the wood splint.

5. Create a 1.5:1 internal combustion ratio for the barrel.