Introduction

For this project, we studied the way a heart valve works, and made models with materials from around the classroom to substitute for a real heart valve. Our team used the base of a plastic water bottle, a cut up CD, duct tape, gloves, a balloon, wooden dowels, plastic straws, metal nails, and hot glue. Our model partially worked in the end, letting some water through at a time.

Before choosing our materials for the final model, we did some testing using the Young's Modulus equation to decide which material would be the most accurate to a real heart valve. We set up a ring stand, and used a weight attached to the material to decifer the Young's Modulus. We then compared our findings to those of the previous experiment on the Engineering Website that we looked at. We found the rubber gloves to be the most similar to the Young's Modulus of the real heart valve.

Content

To start off our experiment, we chose three different materials that we felt would provide elasticity. We chose a rubber band, a glove, and a balloon. We then cut these materials to produce a shape that would allow us to find the cross section. We then measured the length (cm) of each material. Then we produced our ring stand and began. We tied each material to the ring, and then attached different sized weights at the bottom. While stretched, we measured the length again to compare and contrast the length pre and post stretch.

Our method for parts 3-5 was a little different. We focused on designing and redesigning our model. Our materials were a vitamin water bottle, a couple balloons, several rubber gloves duct tape, two wooden dowels, a CD, and 2 small nails. Additionally, we used a hammer, hot glue, and scissors. Using the redesign method, we were able to make a better model each time.

When we compared the length pre and post stretch, we found a significant difference. This enabled us to conclude that these materials did hold high elasticity and would therefore be suitable for our heart valve model. We calculated the Young’s Modulus for three different materials: Balloon, glove, and rubberband. We found that the Balloon’s Young’s Modulus is 3.38 x 10^11, the glove’s Younng’s Modulus is 1.54 x 10^7. The rubberband had a Young’s Modulus of 3.01 x 10^7. We created a model that represented the heart valves. It included two different elastic pieces that had different elasticitys to model accurately. We used a rubber band and a glove to achieve this. The water passes through when poured and stops when the pressure is lessened.

Reflection

During this project, my team and I discovered the right balance of professionalism and friendship required to communicate effectively. We were able to seriously discuss deadlines and plans, while not crossing any boundaries or making anyone uncomfortable. We were especially good at delegating duties in our group. One person would make sure we were on schedule, and another would keep track of all of our important documents. Our team was good at collaborating as well. We did a lot of successful discussion and brainstorming.

We could improve on being better conscientious learners. Our team would have been more productive in class if we had . We tended to talk a lot in class instead of actual getting work done. We also left a lot of tasks to the last minute. They all added up more than we expected them to, and we ended up doing a lot of work at home when we could have done it in class.