4 Type of Heat Transfer Mechanism Involved in Device Cooling

An electric device cooling involves transferring heat from inside the enclosure and discharging it to the surrounding air. Several heat transfer mechanisms like convection, conduction, thermal radiation and evaporative cooling exist in the process. If you are a beginner to these terms, read this content and hone your knowledge with the concepts. In case you are looking the best handbook to study it, get the 6th Edition of Fundamentals of Heat and Mass Transfer Solutions Manual online.

Mechanism Types

1. Conduction: Conduction is the process of heat transfer when its energy is transmitted through a solid surface. Not only in solids, in liquids to the process takes place where its particles are closer together, and in gases where particles are further apart.

2. Convection: Convection is the process in which heat is transferred from the surface using gaseous elements like air. It is naturally occurred due to heat and is replaced by cooler air. Its amount may be improved by using a fan to increase the flow of air.

3. Radiation: Radiation is the process where heat energy is radiated through the air in the form of electromagnetic radiation. It is effective for high-temperature sources like sun, and less effective at ambient temperatures on earth.

4. Evaporation: The phenomena in which liquid state turns into the gaseous state is called evaporation. It is a type of vaporization that occurs on the liquid surface and changes into the gaseous state. When the liquid molecules collide, they transfer energy to each other based on their collision.

Forms of heat transfer used to cool device.

Passive Cooling

Passive cooling is the design approach in which heat gain control, and its dissipation is focused. To improve the thermal comfort of structure with low energy or no energy consumption, this process is followed. The ambient air temperature should be lower than the ambient temperature. However, this method is not suitable for temperature-sensitive components at high ambient temperatures.

Forced ventilation

The effect of convection can be increased by the use of fans that increase the airflow through the enclosure. Cold air is drawn into the floor of the premises, and hot air is released above. Fans should be fitted with filters to limit the dirt ingress that may damage its parts. To ensure that the electrical components are not warm, the ambient temperature should be below the maximum desired enclosure temperature.

Heat pipe technology

Heat pipes came into existence in the 1960s. They are an almost powerless method for enclosure cooling. It consists of an empty copper tube partially filled with liquids such as alcohol or water. Because of low pressure, the liquid at the bottom of the pipe boils when it absorbs heat from the air inside an enclosure. The steam rises to the top of the pipe, where it is cooled and condensed by air outside the device.