For the Design a Heart Valve project, each team had to build a working model of a valve that allowed water to flow freely in only one direction—like the aortic valve in the human heart. First we had to test some materials to determine what would work well for this task. My group tested some foam, a rubber tube, and a plastic tube. We tested these materials to find their Young's Modulus values to determine whether or not they would work well for our model. The Young's Modulus value of an object reflects its stiffness and how able it is to be bent or stretched without being deformed. It is measured as a ratio of stress (Pa) to strain. We used a hanging spring scale to measure the values necessary to calculate the materials' Young's Modulus value, which we then graphed. After sketching the aortic valve to better understand how blood flows through it, we began designing our heart valve model using the materials we tested. After creating a number of failed prototypes, we ended up using a small metal ball and balloon to allow water to flow one way but not the other.

Part 1

Part 2

Blood Flow - The heart pumps blood from the right atrium through the right ventricle into the pulmonary arteries in the lungs. After being saturated with oxygen by the lungs, the blood is pumped around the body to provide oxygen to all the cells before returning to the heart through the pulmonary veins. The blood passes through the left atrium, left ventricle, and aorta before being recycled through the body or removed by tissues and replaced with new blood.

Elasticity - Elasticity is the measurement of an object's or variable's sensitivity to change. The elasticity of the heart enables it to pump blood through its chambers by expanding and contracting muscles to regulate blood flow.

Heart Valve - The heart uses valves to regulate blood flow by allowing blood to flow in only one direction. These flap-like valves are situated within the ventricles of the heart.

Strain - Strain is the measurement of how much an object can stretch before it is deformed. Typically, the more elastic an object is, the more strain it can endure without being deformed.

Stress - Stress is the force per square unit of area—typically measured in Pascals (Pa)—applied to materials by external forces.

Valve - A valve is a device or natural structure that regulates, directs, or controls the flow of a fluid by opening, closing, or partially obstructing various passageways.

Young’s Modulus - Young's Modulus calculates the stiffness of an object, determining how easily it can be bent or stretched. It can be calculated using the equation below:

F = Y * (∆L/Lo) * A

During this project, my group did a great job communicating. We effectively worked together and delegated some tasks to improve efficiency. We also did a great job thinking critically: we had a few set backs with our heart valve model, but managed to overcome them through perseverance and thoughtful solutions, such as changing our materials or even design as necessary.

Honestly, I felt pretty lost during this project when I first came back, but my group supported me and filled me in on everything. I was able to help in many different aspects of the project, including the design, calculations, and report. I think I did a good job suggesting ideas, but I wish I had gone to search for new materials sooner—I went to Target and found some Ball jars with two-piece lids that were water tight and could've been a good solution to our leaking problems. But, in the end, we managed to fix our model just using supplies from the classroom.