Rather than deciding between which type of calorimeter to use, we have decided to construct both and run the experiments. This will allow us to find which device is more accurate in determining the energy density. In addition to determining which method is more accurate, the addition of a second device will help us isolate areas of inefficiency, including, but not limited to, loss of heat and oxygen deprivation.
Our first calorimeter will express a similarity to Figure 1 shown below. Rather than incorporating a drought shield, we will use a Styrofoam container, similar to the type that contains dry ice. This method will contain a majority of the heat that would normally be lost in atmosphere as Styrofoam is an excellent insulator. A thin can containing water will be suspended above a flash filled with our biodiesel. The flask will have a wick that we will ignite. This design is rather simple, but should increase our efficiency over the design in Figure 1.
The second calorimeter is a slighly more complex design as it introduces the combustion chamber. This chamber will be submerged underwater in a container that will house the biodiesel burning. The heat released by the burning will increase the temperature of the surrounding water. The complexity introduced here is that we now have to consider providing oxygen to the reaction process since it takes place under water. Our solution is to inject oxygen through the use of metallic tubing, and to allow exhaust gasses to escape. Again, our goal is to create these devices using low cost materials that are easily accessible for third world countries. So each component we introduce is carefully thought of before it is implemented.
Our next challenge is to determine exactly how we are going to ignite the biodiesel for our second design. Since the fuel will be isolated in a chamber below water, we will not be able to ignite it with a lighter. We are considering the idea of a rapid burning fuse. The fuse will allow us to ignite the fuel from the exterior of the chamber.
What are the main differences in results between the two calorimeters?
ReplyDelete-Group1
Our designs are based off of two designs for calorimeters. The first one is a simple and cheap design often used to demonstrate calorimetry to students. The second is much more expensive and is known as a "bomb calorimeter." This is used in labs to most accurately determine accurate energy content of materials. Comparing the original designs, the bomb calorimeter yields much more accurate results.
DeleteHowever, since our designs are modified versions of the original designs using extremely cheap materials, it is expected that neither design will be nearly as accurate as a real bomb calorimeter. In this case, our project also seeks to determine which of our designs will yield better results. We predict that the second design will yield slightly better results because it involves more insulation than the first.
-Golam