Weekly Updates

Week 1: Formation of Teams and Brainstorming
In this week's lab, teams were formed and the brainstorming process began. Research was done regarding heating pipes and their uses. The project is centered around creating a heating system which will keep the water in animal troughs from freezing in the wintertime. It was determined that copper would be the best to use for the pipe since it is a very conductive material and it is compatible with the working fluid- water. This combination of the compatibility materials depends on the operational temperature range of the system.

Week 2: Continued Research and Design
In this week's lab, a design for the system was proposed and it was discussed whether it was viable with the materials that were being used. Some research also had to be done on how a vacuum could be created using materials listed in the proposal and any other additional materials that may be needed. In addition, the materials will either be ordered online or bought from Home Depot. The blog was also edited and formatted in such a way that the heading "Weekly Updates" was added, in addition to "Project Overview." The current probable design of the heat pipe is shown below:

Figure 1: Initial Heat Pipe Design

Figure 2: Initial Heat Pipe Design Close - Up

Week 3: Finalized Design and Materials 

In this week's lab, the heat pipe design was finalized. Accordingly, the required materials and equipment to build the heat pipe will be listed. Since some of the equipment will have to be bought, it will be done by the end of this week. The most probable option for buying the equipment is Home Depot. Also, suggestions and ideas will be put in as to how to test the heat pipe. Below is the final design of the heat pipe:

Figure 3: Finalized Heat Pipe Design 

Copper Pipe: 24" Length, 0.62" OD, 1/2" inner diameter, $4.11

Copper End Cap: $0.67

Threaded End Cap: 1/2" lead-free brass flare cap, $3.74

Threaded Adapter: 1/2" copper adapter, $1.42

Aluminum Sheet: 6" x 18" x 0.0329", $8.97

Wire Mesh: Aluminum Insect Screen, 36" x 84", $7.48

Figure 4: Copper Pipe CAD Model

Figure 5: Mesh Wire CAD Model

Figure 6: Heat Pipe CAD Model

Week 4: Construction

In this week's lab, the materials needed for the heat pipe were assessed and purchased. The items purchased were the same as decided in week 3. During class, the 1/2" copper pipe was cut down to be only one foot in length. This would allow the pipe to fit with the one foot glass pipe in which it would harness solar energy. The pipe was cut using a pipe cutter. The end cap and threaded adapter were soldered to the copper pipe. This would allow for the threaded brass cap to seal the working fluid inside the copper pipe. 

Figure 7: Copper pipe with end cap and threaded adapter 

Figure 8: Threaded adapter soldered to copper pipe

Figure 9: End Cap soldered to copper pipe

Figure 10: End Cap CAD Drawing

Additionally, the wire mesh was cut into 5" x 12" sheets to be formed into cylinders to go inside the copper pipe.

Figure 11: Wire mesh 5" x 12" sheet

Figure 12: Wire mesh within copper pipe  

Figure 13: Front view of wire mesh within copper pipe

The aluminum sheeting was also cut into two 3/4" x 5" pieces to act as heat fins to improve the absorption of heat.

Figure 14: Two 3/4" x 5" aluminum sheets 

Figure 15: Brass end cap on threaded adapter

Week 5: Construction and Testing

In this week's lab, the aluminum heat fins were taken to the machine shop to be attached to the copper pipe, but since they are different materials, there is not a simple way to fasten the two. As an alternative, a copper plate could be used instead, or thermal paste and an epoxy might be able to fasten the aluminum plate. The pipe was filled with the working fluid, distilled water, to prepare for testing. 

Figure 16: Fusion 360 Drawing of threaded end


Figure 17: Fusion 360 Drawing of Brass cap

Week 6: Testing

In this week's lab, the testing rig was used to assess heat conductivity. Temperature probes were attached to the end being heated and the opposite cap to measure heat in degrees Fahrenheit. The initial temperature for the heat applied side was 102 degrees, and the opposite end was 82 degrees. The temperatures plateaued at around 156 for the heated side, and 162 for the farther end, after a total of 590 seconds.

Table 1: Heat transfer of copper heat pipe over time Test 1

Figure 18: Graph of testing 1

Week 7: Testing and Modifications

In this week's lab, we tested our heat pipe with an improved testing method. One person held the temperature probes to ensure that the probes consistently recorded the temperature and did not shift positions. Another person read off the temperatures in the order from the heated end to the end to which the heat is being transferred. The final group member recorded the times and temperatures into an Excel spreadsheet. The pipe stabilized at 570 seconds with 168 degrees at one end and 172 degrees at the other end, and passed equilibrium at around 530 seconds.

Table 2: Heat transfer of copper pipe over time Test 2

Figure 19: Graph of testing 2 

Week 8: Continued Testing and Final Presentation preparation 

In this week's lab, the heat pipe was going to be tested using tap water rather than distilled water to see how the system changes with different working fluids. However, due to the lack of testing resources, and the numerous other groups, it was not possible to test today. The final presentation preparation began and the slides began to be filled with content. 

Week 9: Final testing, report, and presentation

In this week's lab, the heat pipe was tested using tap water. The results showed that tap water is less effective than distilled water, but the temperatures still were headed towards convergence. 

Table 3:  Heat transfer of copper pipe over time - Test 3: Tap Water

Figure 20: Graph of testing 3

Week 10: Final Report and Presentation

In this week's lab, the project was wrapped up by giving a presentation and turning in a final report which summarized the results from the testing, including further changes which might be made. It also highlighted challenges we had throughout the course of the project and how these were resolved. 

The final presentation can be found here: https://docs.google.com/presentation/d/1rcHhcFqWfSnob7M7_D6jSumGscJ1PT6UbGUXybXpqO0/edit?usp=sharing