The Aluminium Heat sink for Raspberry Pi is an aluminium heat sink kit that is used for cooling the chips microprocessor. The heat sink is attached with thermally conductive adhesive tape that helps in efficiently cooling the Pi.
Why is it necessary?
A heat sink is designed to maximize its surface area in contact with the cooling medium surrounding it, such as the air. A heat sink transfers thermal energy from a higher temperature device to a lower temperature fluid medium. The fluid medium is frequently air, but can also be water, refrigerants, or oil. If the fluid medium is water, the heat sink is frequently called a cold plate. When the airflow through the heat sink decreases, this results in an increase in the average air temperature. This in turn increases the heat sink base temperature. And additionally, the thermal resistance of the heat sink will also increase. The net result is a higher heat sink base temperature.
All you need to do is remove the heatsink protection and stick it on the raspberry pi. The heat sink has an adhesive film on the back that is easy to mount on the chip by pressing it gently. The heatsink will stick to the chip and cool it.