Heat conduction in a Fin

FADI FARES

KARA COX

BEN HOWLAND

Outline

Introduction Objectives Apparatus Procedure Safety Results and Discussion Error Analysis Conclusion

HEAT CONDUCTION

Heat transfer is energy due to temperature difference

the rate of heat transfer in a certain direction depends On the temperature difference per unit length

The fundamental modes of heat transfer are conduction, convection and radiation

The best example of heat transfer is the cooling or heating system

Objectives

Develop a solution to the dimensionless heat conduction equation

Compare the theoretical profile predictions with the actual measured temperature profiles for both thermometers

Calculate the rate of heat removal for each fin Compare the performance of the two

thermometers and comment on their accuracy and general strengths and weaknesses in use.

Apparatus

Figure 1: Fin placed on a hot plate

Figure 2: Thermal Gloves

Apparatus Continued

Thermocouple thermometer IR thermometer www.hcs77.com www.coleparmer.com

Procedure

Turn on 3 hot plates

Place the large fins facing the group on the hot plates, heat to 200 °C

Begin measuring the temperature of the base plate with both IR and thermocouple thermometers to ensure the temperature is 200 °C

Begin measuring the temperature along the fin at one-inch increments base to edge (8 readings) record values

Repeat for all 3 fins record values

Flip all fins 180 degrees (short fin facing the group)

Take temperature measurements at 1 inch increments along the short fin (5 readings) record values

Repeat for all 3 fins record values

After all reading are taking, turn off the hot plates

Procedure Continued…

Figure 5 : Measuring Procedure

Safety Assessment

Working with hot materials

Wear thermal gloves to protect hands from burns

Relevant Equations

Theoretical Model Code (MATLAB)

Dimensionless model code for Aluminum Long fin

Dimensionless model for Aluminum Long fin

Results

Results Continued…

Results Continued…

Results Continued…

Results Continued…

Results Continued…

Thermocouple vs. Infrared Comparison

Advantages Disadvantages

Thermocouple

•Direct temperature reading•More accurate

•Contact angle affects results

Infrared•Can use at a distance•Measurement can be disrupted

•No direct contact•Contact angle affects results

Discussion

Data matched the theoretical model trends Large gap between data and model for aluminum

fin and copper fin Copper has the highest thermal conductivity Stainless steel has the lowest thermal conductivity Thermocouple is more accurate Model is a function of distance from the base to the

surface point of reading The heat flux from the plates vary

Error Analysis

Time of fin to hot plate exposure IR reads at a distance Air flow affect IR reading Thermocouple contact angle Variance between hot plate temperatures –

not heated at a constant rate

Conclusion

Thermocouple is more accurate thermometer

Copper has the highest thermal conductivity Stainless steel has the lowest thermal

conductivity Copper had the highest rate of heat transfer Stainless steel had the lowest rate of heat

transfer