Transcript Heat Sink Calculator - Ira A. Fulton College of

Jed Goodell
Jesse Williams
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
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
Equations Used:
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
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
Calculator
 http://students.cs.byu.edu/~jgoodell/heatsink.html
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.
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’