1. Jed Goodell Jesse Williams

2. Introduction Problem How much heat does a particular heat sink dissipate How many fins are needed to dissipate a specific amount of heat Objective To create a Heat Sink calculator that can: Determine heat dissipation for a given number of fins Determine number of fins for a given heat dissipation

3. Multiple Problems: Solved problem in Excel Compared with Output Forced Convection Laminar Flow Aluminum, Copper, and Steel Solve for Heat Dissipation Solve for Number of Fins Turbulent Flow Aluminum, Copper, and Steel Solve for Heat Dissipation Solve for Number of Fins Free Convection Aluminum, Copper, and Steel Solve for Heat Dissipation Solve for Number of Fins

4. Equations Used:

5. Test Problem Inputs: Type of flow: Laminar Material: Aluminum Base Thickness: 0.008 m Fin Length = 0.01 m Fin Width = 0.005 m Fin Depth = 0.1 m Base Temperature = 323 K Air Temperature = 300 K Wind Velocity = 3 m/s Number of Fins = 17 / Needed Heat Dissipation = 30 W

6. Results When solving for Q 30 W (7mm spacing) When solving for number of fins 17 Fins For Free Convection 19 W (19mm spacing) Calculator also Displays Total Surface Area Fin Efficiency Overall Efficiency Optimum Fin Spacing Average Convective Coefficient

7. Calculator http://students.cs.byu.edu/~jgoodell/heatsink.html

8. Conclusions Material does not significantly affect the number of fins or heat dissipation. Surface and air temperatures, air velocity, and number of fins significantly affect heat dissipation. Surface and air temperatures, air velocity, and heat dissipation significantly affect the number of fins.

9. References Fundamentals of Heat and Mass Transfer, Incropera et al. Chapters 7 & 9 Material/Air properties poly-fit from Appendix A Title picture from Wikipedia, ‘Heat Sink’