The stefan boltzmann constant σ has a value of 5 67 10 8 w m 2 k 4.
Calculation of surface area of heatsink.
Typical values are listed in the article the importance of radiation in heat sink design.
S lat lateral surface area.
The surface area of a square pyramid is comprised of the area of its square base and the area of each of its four triangular faces.
The highest operating temperature that a semiconductor in an electronic device can withstand is called its junction temperature.
The heat transferred from the junction to case multiplied by the junction case.
Estimate the overall volume of the heat sink required to cool a heat source by using the following equation.
Base sa a 2.
Total sa a 2 2a a 2 2 h2.
Please use our online heat sink calculator for this step.
H air film convective coefficient a exposed surface area of the fins.
Any heat sink with a larger value of h x a will be able to produce a lower source temperature.
Heat sink sizing calculator rough estimate.
Next the radiation heat transfer from the area a 2 given by equation 10 is calculated.
The variables ε is the surface emissivity of the heat sink.
However if h a p k is greater than 1 00 the fins will insulate and prevent heat flow.
The metal surface is supposed to be untreated shiny metal colour and the thickness should exceed 1 5 mm.
A side length.
Heat sink sizing calculator v4.
This temperature is commonly higher than the temperature of the device s exterior and its case.
Concentration of the heat source over an area much smaller than heat sink base is not taken into account in this calculator.
Given height h and edge length a the surface area can be calculated using the following equations.
Heat sink design and optimization i.
This calculator should not be used in instances where the heat source is much smaller than the base of the heat sink.
Fins are used to increase heat transfer area and provide a cooling effect.
E lateral edge length.
Where a hs is the surface of the metal plate in cm 2 and r th hs a is the thermal resistance from the heat sink to the ambient in c w.
The p rocedure for calculating the radiative heat transfer coefficient for the u channels is outlined in the book by ellison ref.
2 u channel interior surface identification 4.
S tot total surface area.
P perimeter of the fins.
Heat transfer by convection of a heat sink with fins calculator and equations.
Is the convection coefficient of the heat sink is the total surface area of the heat sink is the temperature of the source being cooled is the ambient temperature.
Krug december 2015.
Lateral sa 2a a 2 2 h2.
Check out the heatsinkcalculator if you need to evaluate these smaller heat sources.
Applications of a heat sink calculator.
