Thermal Conductivity Device Design

Materials:

Hot Plate

Aluminum Box x2

Plastic Tubing

Duct Tape

Fiberglass Insulation

Weight

Thermal Paste

Thermocouples x2

Electric Tape

 

Procedure (Design)

Top (Fig. 1.1): Simplified Version

Bottom (Fig 1.2): Final Product

This procedure is designed to address the design from the bottom up.

  1. The heat source, in this case, the hot plate should be turn on to the highest setting.
  2. The lowest aluminum box should be filled with water and allowed to boil. This ensures a near constant temperature of 100°C. We machines two 0.5 mm holes in either side of the box to allow for more ventilation
  3. The lid on top of the lowest aluminum box should be set up as follows:  (Figures 1.3 &1.4)                                                                                                                                               
  4. Cover the top and bottom of the sample with a thin layer of thermal paste. The layer should be thick enough that when the sample is placed on top of the box lid, it should stick to the lid and not come off.
  5. The top box should be covered in fiberglass insulation on all sides except the bottom. The bottom of the box should be set up the same way as the lid of the bottom aluminum box. For reference, see Figure 1.3 and 1.4                                                   
  6. One corner of the top aluminum box should have a hole machined into it, along with a tube in order to carry away the melted ice in the box.

 

Procedure (Experiment)

  1. The experiment should look like Figure 1.1. The lowest aluminum box should have boiling water, and the top aluminum box should be filled with ice. The more ice there is, the better.
  2. Place a weight on top of the entire experiment to ensure thermal connection between the sample and the aluminum boxes
  3. Start the timer, or Logger Pro, once you place the ice in the top box.
  4. Stop the timer once all the ice is melted
  5. Use the Fourier Equation to determine the k-constant