Electric Cooking Pot
Week 3
Prototype Planning
Today we finalized our plans for the first prototype we plan on making during lab this week. We are going to test the diodes and configuration using JB Weld, copper wire, solder, and MgO on a small, cheap bowl. We plan on utilizing a maximum of five diodes to see if the our plan will be feasible on a larger bowl. Our prototype aims to reduce heat emission to prevent diodes from breaking and effectively heatsinking the diodes to the pot so that the diodes stay cool and the pot heats up.
Week 4
Design #1
This week in shop we worked on gluing the diodes onto the bowl. We mainly focused on the mix of the JB Weld and the Magnesium Oxide and experimented with different quantities of each to find the perfect mix. Afterwards, we glued the diodes and copper wire onto the bowl and tested to make sure that the system was not short circuiting in any area.
Week 5
Design #2
This week we altered the design by changing the placement of the diodes from the top of the pot to the side of the pot. We also changed the JB Weld and Magnesium Oxide mix by adding acetone to the mix. The addition of the acetone caused the mix to be thinner, however we added way too much acetone and it caused a lot of cracking. We look forward to seeing how much heat we can produce in the system next week!
Week 6
Week 6
Communities Research
After Ryan Alaniz's talk last week, we decided to dedicate week 6 to learning more about Malawi and our target communities. We felt that it was important to gain a better understanding of the community before continuing with our design. We learned that Malawi is one of the most underdeveloped countries in the world, but they have the friendliest people. Check out our Target Communities page to read much more!
Week 7
Testing
In lab this week we tested our second design to see how much heat we could run through the diodes before they burned up. We choose a baseball measurement of roughly 4V and 6.5A and after 6 minutes the temperature of the composite got up to 80 degrees Celsius and the diodes got up to 70 degrees Celsius. Then, we increased to 5.5V and 14.5 and the composite increased to 119.2 degrees Celsius and the diode temperature increased to 135.7 degrees Celsius. Shortly after this max temperature, the diodes popped and we could not run any more current through our system.
Week 8&9
Composite Testing
During the weeks of 8 and 9, we came up with two different ratios of JB Weld, MgO, and acetone and stuck them on the pot.
Ratio 1: .338 oz JB Weld, .16 oz MgO, and .1 oz acetone
2.5 oz JB Weld / 1 oz MgO
Ratio 2: .35 oz JB Weld, .176 oz MgO, and .05 oz acetone
2 oz JB Weld / 1 oz MgO
After they had time to settle, we tested both of the composites by running 3.5 V and 7.4 A through the system over 620 seconds. The first ratio heated the pot up to about 24 degrees Celsius while the second ratio heated the pot up to about 29 degrees Celsius (as seen by the red line in the graphs). These ratios are significant in creating the composite for our final project! Stayed tuned!!
Week 10
Final Prototype
During week 10, we put together our final prototype. We put diodes around the entire pot and set them in place using thin thread. We decided to go with the first ratio of .338 oz JB Weld, .16 oz MgO, and .1 oz acetone. Since we were using 20 diodes as opposed to 4, we multiplied this ratio by 5 and ended up using 1.7 oz of JB Weld, .8 oz of MgO, and .5 oz acetone. However, as we were adding the MgO, we noticed that the mix was starting to harden much faster than we wanted, so we ended up only using .6 oz of MgO.
We look forward to testing and possibly cooking before our final presentation!
