User:Nkim5706/ENES-100/Project 3/CDIO

Problem Statement

 * Figure out how Stirling engine works. Assemble Stirling marble engine kit and make it work properly.

Stirling engine

 * Here is a useful website to understand what is Stirling engine and how it works.
 * http://en.wikipedia.org/wiki/Stirling_engine Wikipedia - Stirling engine
 * http://en.wikipedia.org/wiki/Stirling_engine Wikipedia - Stirling engine

Striling marble engine - The first attempt

 * (1)Using the end piece of a balloon cover the large end of the stopper and tight them with rubber bands as storng as possible.
 * (2)Connect the hose fittings into the other end of the stopper.
 * (3)Assemble the aluminum brakets and the hinge.

Test

 * After 30 seconds heating the end of the test tube, the balloon is supposed to be expanded. However, there is no expansion at all which means there might be a leaking part.
 * The easiest part which has leaked is the balloon, so taking the machine apart again and test it if it has a hole the air can be leaked.
 * Put the rubber stopper with the hose in a cup with water and blow the air into the hose and see if there's a hole.

Possible implementation and Next Steps

 * Replace the balloon with new balloon with no holes. After cover the rubber stopper with the balloon, tight it with two or three rubber bands as strong as possible, so that there is not any leaking part.
 * Put the rubber stopper with the hose in a cup with water and test if bubbles are formed.

Striling marble engine - The second attempt

 * Replace the ripped balloon with the new one and wrap the rubber stopper with it.


 * However, the balloon is not expanding enough to tilt the test tube.

Test

 * After 30 seconds heating, the balloon was expanding.
 * After 3 minutes heating,the marbles started to move to the left and the test tube tilted.
 * To make the marbles slide down to the right, there should be a certain weight or force at the right end of the test tube where the robber stopper is.

Possible solutions and Next Steps

 * (1)First possible solution: put less heat, so that less expansion of air occurs.
 * (2)Second possible solution: put some weights at the right end of the test tube, so that the force applied to the test tube makes it to tilt.

[Solution 1 : Apply less heat]

 * Place candle only 3 minutes until the marbles roll to the left and remove it. However, the marbles still don't roll back to the right. This solution doesn't work.

[Solution 2 : Cool down the test tube]

 * Make the right side of the test tube cooler so that the pressure decrease more, and it causes the volume also decrease.
 * This solution also doesn't really work.

[Solution 3 : Apply force - hang a weight at the right end of the test tube]

 * Put a small ring to the hook so that the force applied downward helps the test tube tilts to the right.


 * The match box is not fixed and keeps moving, it causes the test tube tilts arrhythmically.