1

A SEMINAR ON

HEAT SINK APPLICATIONS

Karnataka Law Society’sVishwanathrao Deshpande Rural Institute Of TechnologyHALIYAL (UTTAR KANNADA) – 581329, KARANATAKA

DEPARTMENT OF ELECTRICAL & ELECTRONICS ENGINEERING

PRESENTED BY: Sameerakhtar A Betgeri VIII SEM USN: 2VD07EE031

2

Contents

• Introduction• What is Heat Sink ?• Need for the Heat Sink ?• Heat transfer principle• Construction and materials• Applications• Conclusion• References

3

Introduction

• Electronic equipment has made its way into practically every aspect of modern life.

• Electronic components depend on the passage of electric current to perform their duties, and they become potential sites for excessive heating.

• The failure rate of electronic equipment increases exponentially with temperature.

• Thermal control has become increasingly important in the design and operation of electronic equipment.

4

What is a HEAT SINK?

A heat sink is a component that is used to provide cooling to an electronic device.

There are mainly two types

1.Passive Heat Sink 2.Active Heat Sink

5

Need For The Heat Sink

• All semiconductor devices have some electrical resistance.

• When the component operates heat is generated.

• The component fails if it temperature rise above permissible value.

• We can increase the Power rating of a component by keeping its temperature down.

6

Heat transfer principle

• Practical heat sinks for electronic devices must have a temperature higher than the surroundings to transfer heat by convection, radiation, and conduction.

• To understand the principle of a heat sink, consider Fourier's law of heat conduction.

• is the local heat flux, W·m−2

• is the material's conductivity, W·m−1 ·K−1

• A is the cross-sectional surface area• -dT/dx is the temperature gradient

7

Cont…

Consider a heat sink in a duct, where air flows through the duct, as shown in Figure.1 below

Figure.1

8

Construction and Material

• Heat sink is a static object.• A heat sink usually consists of a base with one or more flat

surfaces.• An array of comb or fin-like protrusions to increase the heat

sink's surface area contacting the air.• Heat sinks are made from a good thermal conductor such as

silver, gold, copper, or aluminum alloy.

9

Advantages and DisadvantagesADVANTAGES:• Heat sinks provide a greater surface area to contact with the air compared

to metal.• The material structure, in turn enables overall better heat dissipation and

convection properties, dissipating heat faster than metal heat sinks without storing heat within itself.

• Component can be used for longer time.• Failure of components due to heating is minimized

DISADVANTAGES:• Cost of the system is increased.• Compactness of the system will be reduces.• For more efficient cooling a extra fan is needed

10

APPLICATIONS

1.Personal Computers2.Soldering3.Batteries

11

Conclusion

From the above report I conclude that use of heat sink in electronic system can increase the life of the component and we can prevent the failure of component due to temperature rise above permissible temperature and enables overall better heat dissipation in the component.

12

References

• http://letsmakerobots.com/files/heatsink.pdf Heat sink basics by electus distribution

references data sheet pdf.• http://en.wikipedia.org/wiki/Heat_sink• www.irf.com/technical-info/appnotes/an-

1057.pdf “Aavid Thermalloy Thermal seminar”, Mustafa

S., El Segundo , CA ,November 2002

13

THANK YOU