Determining Temperature Differences Using Thermocouple Tester and Thermo-imaging Camera - Lab Report Example

Submitted: Oct 27, Performed: Oct 20, Lab Section: Diffusion and Premixed Flame Gregory E. Gorbett Lab TA: Matthew Determining temperature differences using thermocouple tester and thermo-imaging camera Abstract The purpose of this experiment is to determine the heat temperature produced by the ordinary candle flame in which the oxygen combines with the fuel at the combustion zone and the laboratory Bunsen burner flame in which both fuel and oxygen are premixed prior to combustion. The difference in temperatures was detected by using a Thermocouple tester and a Thermo-Imaging Camera. The former works by heat transfer of conduction while the later by heat transfer of radiation. The results obtained show that the temperature of the diffusion flame by using Thermocouple tester and thermo-imaging camera was 1126 °F and 1200 °F respectively. On the other hand, the temperature of the premixed flame by using the Thermocouple tester and thermo-imaging camera is 1671 °F and 500 °F respectively. Introduction Fire personal should be aware of the sources and causes that lead to a fire and its mode of spreading in order to prevent or control the spread of fire and in turn save lives and property. This could be made possible by understanding the fire dynamics which is the “interrelationship of fuel, heat, oxygen, chemical reaction, and the physical world and the study and control of these components provides safety for humans and structures” (Gorbett and Pharr, 2011,p.g.7). Additionally, this experiment also shows that the heat temperature of fire flames varies depending on how oxygen is provided to the combustion reaction. Two kinds of flames have been used for this experiment, namely diffusion and premixed. The diffusion flame is defined as “the flame resulting from fire where oxygen mixes with the fuel at the combustion zone” (Gorbett and Pharr, 2011,p.g.309) that gives out a yellowish red fire color and produces less heat when compared with the premixed flame. Candle was used as a model of diffusion flame and it has flammable limits with heat transfer in the conduction, convection and radiation mode. The premixed flame is defined as “a flame for which the fuel and oxidizer are mixed prior to combustion, as in a laboratory Bunsen burner or a gas cooking range” (Gorbett and Pharr, 2011,p.g.312) that gives out a blue fire color and more heat than the diffusion flame. The heat temperature produced by the two flames was measured using a Thermocouple tester, and Thermo Imaging Camera. A Thermocouple tester is a device that is used to measure the temperature through the principle of heat transfer by conduction. The Thermo-Imaging Camera (T4 Max) is a device measure the temperature by heat transfer of radiation. As hot objects have more energy than cold objects the thermal imager translates the energy waves produced to a viewable image that is representative of the heat capacity of the objects and the resulting heat temperature is displayed on the side screen. In the picture hot objects will show as white patches while the cooler objects will show as black patches and the other objects between these hot and cold areas are shown as gray (Bullard, 2011). Materials required PPE (protective glasses, and gloves) Candle flame (diffusion flame) Bunsen burner (premixed flame) Lighter Thermocouple tester Thermo-Image Camera. Procedure For the diffusion flame the candle is ignited and the heat temperature is measured using the thermocouple tester by placing the thermometer probe in the middle of the candle flame. The resulting temperature in the probe is recorded. The thermo-imaging camera is made to focus on the flame and the result is recorded. For the premixed flame the Bunsen burner is ignited and the thermometer probe is placed in the middle of the Bunsen flame and the resulting temperature is recorded. The thermo-imaging camera is then focused on the Bunsen flame and the result is recorded. Experimental Results The results of both the experiments carried out are provided below. First test: Temperature Tool Tool 1126 °F       Diffusion flame (candle flame) Thermocouple 1200 °F Diffusion flame (candle flame) Thermo-image Camera Second test: Temperature Tool Tool 1671°F Premixed flame (burner flame) Thermocouple 500 °F Premixed flame (burner flame) Thermo-image Camera The temperature recorded from the candle flame (diffusion flame) by using the Thermocouple tester and thermo-imaging camera are 1126 °F and 1200 °F respectively. The temperature recorded from the Bunsen burner (premixed flame) by using the Thermocouple tester and thermo-imaging camera are 1671 °F and 500 °F respectively. Discussion of Results The result from the first test by which the heat temperature of the candle flame (diffusion flame) is determined using Thermocouple tester is 1126 °F. The placement of the thermometer probe in the middle of the candle flame results in accurate heat temperature measurement by the probe based on the heat transfer through conduction. Heat transfer of conduction is defined as “the transfer of energy in the form of heat by direct contact through the excitation of molecules and/or particles driven by a temperature difference” (Gorbett and Pharr, 2011,p.g.308). The heat temperature measured using the Thermo-Imaging Camera by focusing the device on the candle flame is 1200 °F. Hot objects are shown as having more energy than cold objects by the termo-imaging camera and these energies are translated to a viewable form by the thermal imager and a heat picture of the objects are displayed on the device screen. The camera uses the heat transfer by radiation as a measure of the temperature. Heat transfer of radiation is defined as “transfer by way of electromagnetic energy” (Gorbett and Pharr, 2011,p.g.312). The results from the second test by which the heat temperature of the Bunsen burner (premixed flame) is determined using the Thermocouple tester is 1671 °F. When the Thermometer probe is placed in the middle of the candle flame it measures the accurate temperature of the candle flame based on the principle of heat transfer by conduction. The heat temperature of the burner (premixed flame) measured by using the Thermo-imaging Camera is 500 °F. While the heat temperature in the premixed flame is normally expected to be more than the diffusion flame, the heat temperature measured by the camera has recorded a lesser reading which could be because the cross air was not in the right location which has resulted in the camera showing a lesser reading of 500 °F as compared to the 1671 °F reading of the thermocouple tester. Conclusion In conclusion, this experiment demonstrates how the heat temperature of the diffusion and premixed flames are determined using a thermocouple tester and a thermo-imaging probe which work on the principle of heat transfer by conduction and radiation respectively. Though the premixed flame shows a higher heat temperature compared to the diffusion flame when using the thermometer probe, a lesser temperature was recorded with the camera which could be due to the presence of cross air in the location where the camera was focused. Thus the premixed flame in which the fuel and oxygen are mixed prior to combustion produces more heat compared to the diffusion flame. References 1. Bullard (2011). How a TI Works. Bullard. Retrieved October 24, 2011, from http://www.bullard.com/V3/products/thermal_imaging/how_a_ti_works.php 2. Gorbett, G and Pharr, J. (2011). Fire Dynamics, First Edition, Person : Upper Saddle River, New Jersey. Read More