NUMERICAL ANALYSIS OF THE USE OF UNIFORM SEMI-POROUS HEAT SINK
MEDIAS FOR CHIP THERMAL MANAGEMENT WITH FREE CONVECTION
by
Eric R. Savery
A Project submitted in partial fulfillment of the
requirements for the degree of
Masters of Engineering
Rensselaer Polytechnic Institute
2010
Approved by __________________________________________________
Ernesto Guiteerez-Mirravette, Engineering Project Advisor
Rensselaer Polytechnic Institute
Groton, Connecticut
September, 2010
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ABSTRACT
This work presents a numerical investigation of the use of metallic porous
materials, for use as a semiconductor heatsink. Specifically what is the optimum
porosity for a porous heatsink to achieve the greatest transfer of heat from a
microprocessor. The heatsink will have a constant size, material thermal conductivity
(ie Material) and geometry. The heat source (ie Processor) will be held at a constant
temperature. By varying the heatsinks porosity the amount of energy that is able to
be transferred to the atmosphere will be analyzed. The results of the each heatsink
are compared against each other and to a standard fin heatsink which are normally
supplied with the processor.
Introduction/Background
Since the discovery of the microprocessor computing power has been becoming
more powerful and consequently been creating more heat. The heat which more
powerful processors create is required to be dissipated else the processor will become
less reliable or fail1. For every 10ºc that you are able to reduce a transistors
temperature the failure of the electronic component is halved1. Therefore the more
heat that is able to be removed from the transistor the greater the reliability is. To
transfer the waste heat from the transistor to the environment requires the use of a
heatsink. A heatsink is a device which dissipates energy from a component to
ambient air by use of natural or forced convection. The heatsink’s ability to dissipate
the heat energy is a function of the material properties, geometry and the
environmental conditions2. Increasing the amount of heat energy which is able to be
dissipated by the heat sink will allow for higher processing speeds at a lower temp.
Below is an example of a simple fin heat sink that would be used on a typical
integrated circuit.
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Figure 1: Fin Heat Sink
This paper looks how the use of semi-porous media with a significant amount of
surface area affects the efficiency of the heat sink to dissipate heat energy from a
computer chip. With the use of a numerical analysis this paper will compare the
efficiency of the standard fin heatsink against a heatsink that uses a semi-porous
material.
Problem Description
Methodology/Approach
Analytical Analysis and Modeling
Resources Required
Analytical Analysis and Modeling
Expected Outcomes
Milestone/Deadline List
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Start
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3
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5
6
7
8
9
10
11
12
14
16
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22
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Proposal
Design Model
Design Contraints
Design Heat Sinks
Numerical Anylasis of Experment
Construct Control Heat Sink Model
Perform Control Calculation
Construct Poruois Material Calculation Model
Perform Porous Material Calculations
Review & Check Calculations
First Progress Report
Compile and Compare
Compile Calculated Data
Analyze Use of Semiporous Material Effectiveness
Second Progress Report
Final Draft
Write Draft
Review of Final Draft
Final Report
9/26/2010
9/26/2010
9/26/2010
10/7/2010
10/7/2010
10/14/2010
10/21/2010
10/28/2010
11/3/2010
10/21/2010
11/4/2010
11/4/2010
11/11/2010
11/11/2010
11/11/2010
11/11/2010
11/25/2010
12/2/2010
Finish
Time (days)
9/26/2010
10/7/2010
11
10/7/2010
11
10/7/2010
11
11/4/2010
28
10/14/2010
7
10/21/2010
7
10/28/2010
7
11/4/2010
7
11/4/2010
1
10/21/2010
0
11/18/2010
14
11/11/2010
7
11/18/2010
7
11/11/2010
0
12/2/2010
21
11/25/2010
14
12/2/2010
7
12/16/2010
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References
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Fundamentals of Thermal-Fluid Sciences; Second Edition, Yunus A. Cengel & Robert H. Turner, © 2005
http://en.wikipedia.org/wiki/Heat_sink
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