10/31/2010 Weekly Report
Team: Solar Lovin'
Subteam: Insulation
Subteam Members: Sarah Clement, Harrison Ko, and Julianne Schwartz
- Construction of the Experimental Oven
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- The entire frame of the oven is complete, and the insulation has been put in place on the five "over-insulated" walls
- The experimental wall, which will hold the different types of experimental insulation, is now complete and ready to be filled with insulation
- Decided Method of Experimentation** Problem: Issues with insulation only appear after a year of the heating/cooling cycle. We must create an environment as closely related to the real situation as possible.
- Solution: Determine the timing of the heating cycle the oven undergoes each day.
- Set the experimental oven to run through as many heating cycles a day as possible, until the insulation has be used for an equivalent of six months
- To-Do** Decide on the exact materials to use for heat sensors (wires have to be insulated to prevent damage from heat)
- Place heat sensors inside the oven and in the experimental wall
- Figure out how to attach experimental wall to the oven. It needs to be easily removable in order to be able to change and test different types of insulation
Subteam: Concentrated Cooker
Subteam Members: Catherine Hanna and Margaret Ding
- Design and Construction Processes
We have integrated our design and construction processes into joint phases. Simply put:
(1) Construct reflective paraboloid: test paraboloid to find empirical focal point (will vary from predicted calculated focal point)
(2) Design and construct remaining frame: upon discovering the height of the focal point, we will know the dimensions needed for the cooking surface and supporting frame
- Paraboloid: Shallow vs. Deep
A deep paraboloid creates impracticalities and safety hazards in the actual use of the concentrated cooker. The focal point would be well inside the paraboloid; this would be difficult to maneuver when actually cooking.
We have decided to construct the more commonly-used shallow paraboloid, which would make the cooking surface framework easier to build. This also gives the user more flexibility when adjusting the reflective surface to receive parallel light.
- Paraboloid: Material
Tim has informed us that he currently has two .016" thick 3' by 4' aluminum sheets, which would be easy to cut (with metal-cutting shears) and experiment with to improve our construction process. We will use these to make the initial reflective paraboloid.
- Paraboloid: Construction Process
In order to create a paraboloid, a flat metal sheet must be cut into a number of pie piece partitions that can be curved upwards in the correct geometry. At first we wanted to cut out curved pieces between the partitions to create petals that would perfectly form the paraboloid when placed edge-to-edge. However, we find it more practical to simply overlap the partitions with the correct calculated width to create a paraboloid shape, not cutting out all excess material. This leaves more room for error since the cutting process is not exact.
- To-Do:
We are currently finishing paraboloid partition overlap calculations, and will start the paraboloid building process Monday, November 1.
Subteam: Small Solar Oven
Subteam Members: Joe Beaudette, Lauren Neilsen, Lief Paulson, and Rachel Philipson
- Prop Rod
o The chosen design consists of a tee with a hole drilled in the flat side to attach the tee to the oven. The rod slides through the straight part of the tee and a screw is used to secure the rod in place at the chosen height.
o Several different prop rods were constructed. We used a large brass tee, a smaller brass tee and a PVC tee. Different sized metal screws were used to hold the rod in place depending on the inner diameter of the tee. In the following weeks we will attempt to run various tests (to be determined) to figure out which design is best
- Small Solar Oven Design
o Final dimensions were chosen and an AutoCAD drawing was made of the frame. The outside and any other components (hinges, latches) of the oven will be added to the drawing as soon as they have been chosen
- To-Do:
o Run tests to determine the best prop rod design
o Build a frame for the small solar ovens using the dimensions we decided on