Reference no: EM131508327

Assignment

Paraphrase the following-

Problem Statement

There are three experiments testing three separate heat transport phenomena's. The first experiment was designed to understand the process behind a thermocouple, it was tested by making our very own thermocouple circuit and using a multimeter for the temperature change with voltage readings. The second experiment looked at radiation and specifically the emissivity and the absorptivity concepts. Three different colored probes, a heating lamp, boiling water, and thermocouples were used to further explore radiation. The third and final experiment looked at fin efficiency with a heating block and natural convection along with calculating the thermal conductivity of one of the rods using insulation and the heat flow equation.

Experimental System and Procedure

Experiment 1: Thermocouples

The experiment started with two wires that both had a copper and constantan part. The ends of one of the wires were both stripped at the ends, just enough to wrap them around each other. Two junctions were formed, both with copper and constantan. The copper wire that was not twisted into the junction, was placed in the multimeter to measure the voltage, one of the junctions was placed in the ice bath and the other end was used to measure temperature. The voltage drop and TC charts were used to calculate the measured temperature.

Experiment 2: Radiation

For the absorptivity experiment, place the three different probes (white, black and unpainted) under a heating lamp on glass wool insulation, Record the data given in thermocouples every thirty seconds for 5 minutes, Repeat experiment three times for statistical accuracy. For the emissivity experiment, connect one of the probes to the thermometer. Place the black probe in the boiling water and set until it reached high temperature. Try to immerse the entire probe in the boiling water so the entire probe will maintain the same temperature. Take the probes out of water and wipe down to remove residual water droplets. Record the temperature with 5 seconds time intervals until the temperature of the probe reaches room temperature. Repeat the same steps for the white and unpainted probe (as shown in Appendix A, Figure 2 and 3).

Experiment 3: Fin Efficiency

Start the experiment by heating up the block (Aluminum) using a high resistance cartridge heater. Let the rods reach a steady state by turning the power block on and waiting for the thermocouple readings to stay relatively constant. Finally, record the surface temperatures every 15 minute for all (24 ports) once it is insulated and when the insulation is removed (as shown in Appendix A, Figure 4). Use these steady-state values to calculate the conductivity of the stainless steel rod in the insulation and after removing the insulation, use the temperatures to calculate the convective heat transfer coefficient.