Radial Conduction lab report. (heat transfer)  

Lab 3 – Radial Conduction Questions

1) Plot the temperature vs. radial distance for the steady state temperature distributions.

a. How did you determine the system had reached steady state?

2) The disc is brass. Calculate the thermal conductivity (k) using Fourier’s Law.

a. DO NOT use the probe in the center of the disc for this calculation. That probe is not sampling the temperature of the metal. (See Figures 1 and 2)

b. How does the calculated thermal conductivity (k) compare to the actual conductivity of brass? Is there a difference? Why?

3) Show method of calculating k value. What assumptions are you making? Do any unknowns interfere with your calculations? Compare with the experimental data and comment on any differences.

4) Determine the convection heat transfer coefficient of the running cold water. (Use water temp as .) Does your answer make sense? If not, why?

5) Plot a few of the transient temperature distributions and comment on the manner in which the temperature changed over the course of the experiment.

a. Did it change in the manner you expected?

6) Comment on any unusual findings or any other salient information in the lab.

THE GEOMETRY OF THE DISC IS AS FOLLOWS:

Figure 1

Figure 2

· The inner radius of the disc is 4 mm. (See Figure 1)

· The outer radius of the disc is 55 mm. (See Figure 1)

· Notice in Figure 2 that probe #1 is in the center of the apparatus.

· Each probe is separated by 10 mm. Probe 9 in Figure 2 sits 5 mm from edge of disc.

· Thickness of the disk is 3.2 mm - slightly larger than the lab handout indicates

· The cooling water pipe is soldered to the disc. The water does not make contact with the brass.