To start the beginning of the second semester, we were told we were given $5,000 to build an outdoor classroom. To build an outdoor classroom, we would have to design a solar water heater, design a turbine powered by wind or water, choose a site for our classroom, test our materials, create a survey for our clients, and build our classroom. My group to help build this, was Cole, Lara, and Emma.
Solar Water Heater
Our first step to building an outdoor classroom, was to provide our clients with warm water. Before building our heater, we learned about convection, conduction, and radiation. Convection is when heat is transferred through water. Conduction is when heat is transferred through a solid object. Radiation is the sun's heat transmitted by neither convection nor conduction. Our class could follow a written lab and blueprints, or we could design our own heater. My group and I decided to design our own solar heater. We thought that if we were able to redirect all of the sun's rays to our copper pipe filled with water, we would gain more heat than the lab's design. We took a piece of cardboard and wrapped it in mylar. Mylar is a reflective covering used in greenhouses to redirect light. We then bent the cardboard into a parabola shape that would guide the light onto our copper pipe. Unlike the many of the other groups, we didn't use any insulation. If we used insulation, it might block some of the sun's rays, and decreasing the amount of sunlight. Also unlike many groups, we couldn't check the temperature our water was at. Our water wasn't exposed to any wind our any other conditions, since our pipe was blocked on both ends. Our water's initial temperature was 13 degrees Celsius (55,4 degrees Fahrenheit). After half an hour, our water was at 31 degrees Celsius (87.8 degrees Fahrenheit). We had 168 mL of water, and had a heat gain of 12,658.5 joules.
Creating A Survey
Since we weren't the clients of our classroom, we had to find out what they wanted. We spent a couple days creating a survey to give to teachers and students. We would give the students a paper survey, and the teachers an online survey. Below is the survey our class created.
Testing Materials
Before choosing our site, we tested different materials to find the best supplies to use for our outdoor classroom. We tested the materials' heat conductivity and water resistance. We tested ground materials, like dirt or tanbark, and building materials, like plywood or brick. We would weigh the materials after being submerged in water and take the temperatures of the materials after being under a heat lamp for thirty minutes.
Finding A Site
Our next step was to choose a location for our outdoor classroom. Our group chose from a selection of three places. Some factors that went into deciding which site to choose were noise level, distance from main buildings, and water/electricity accessibility. We finally settled on the area behind the cafeteria. This area is quiet, close to the main buildings, on level ground,
Creating Our Design
After choosing a site, we had to construct our design. We knew we needed to stay under our $3,000 budget, so we chose a simpler, cheaper design. Our design has 8 slanted picnic tables in a semicircle surrounding a lectern. The reason for the slant was so every student could see the speaker. All the wood is pressure treated, and has a low heat capacity. This will retain heat better, making for a comfortable seat. To put the tables and lectern together, we will attach the surface boards to supports with wood screws that will then be bolted onto thick posts. These posts will be set 6 inches into concrete. We originally planned for a shade structure, but that wasn't in our budget, so for an alternative, we would plant a weeping willow tree. Willow trees also do not drop their leaves in the winter.
Wind Turbine Lab
While we were about halfway through making our presentations and designs when we had to make a wind turbine lab. We would create different turbines to test horizontally and vertically. We measured how efficient these turbines would be by how much voltage they generated. We discovered that using metal for a wind turbine creates more watts of energy than paper or cardboard. We came to this because the metal pinwheels we made were the exact same as the paper ones, but the metal ones spun faster. Another thing we noticed while testing, was that at high speeds the paper pinwheels ripped apart while the metal ones stayed intact.
Concepts we used in our Outdoor Classroom
Convection - The transfer of heat through a fluid.
Conduction - The transfer of heat through a solid.
Radiation - The transfer of energy by electromagnetic waves.
States of Matter - The three states of matter are solids, liquids, and gases.
Laws of Thermodynamics 0th - The zeroth law states that if two systems have equal heat and a third is equal to the second, then the third system is equal to the first. 1st - The first law states that energy is neither created nor destroyed. 2nd - The second law states that entropy always increases in a thermal system. 3rd - The third law states that no system can contain zero energy.
Atom - The smallest unit of physical matter.
Pits and Peaks of our project
This is the longest project that we have done in our freshman year. It took a total of about three months and a lot of work. Here are our pits and peaks of the outdoor classroom project. My first pit is our work ethic. During the beginning, all four of us were working hard with many unique ideas. This productivity lasted until the last two weeks. We had actually finished the slideshow, the blueprints, the script, the model, and the spreadsheets. Except we didn't do anything but practice our presentation for the rest of the time we had. I think we should have been perfecting the blueprints or maybe even add something more to the design since we had an advantage of extra time. My first peak is how well our group communicated. We each had our task to do and we completed it efficiently. We also shared ideas well and were able to accept different plans from our own. At presentation night, since our script was very organized, our pitch went very smoothly. While doing all of our labs, we were also able to work together and divide the work evenly. My second pit is our creativity this project. I think that maybe we should have included something more. I just think that our design had something missing. Even though our design included all the necessary factors, I think we could have had something extra to make our classroom stand out more. This could have been maybe a whiteboard, a shade structure, or at a unique location. My second peak is our time management. we were all working efficiently on the labs and our outdoor classroom. It was very rare for any of us to be on our phones, so we were very productive when we had a lot of work to do. Emma usually worked on the script, Lara usually did the presentation, Cole did the 3D modeling, and I did the blueprints. This allowed us to complete a lot of work and finish with a couple weeks to spare.