Six Cooling Methods for Electronic Devices

With the rapid development of high-frequency, high-speed, and integrated circuit technologies, the total power density of electronic components has greatly increased while their physical size continues to shrink, resulting in higher heat-flux density. High temperatures inevitably affect the performance of electronic components, making efficient thermal control essential. Solving the heat dissipation problem of electronic devices has therefore become a key focus. This article provides a brief analysis of heat dissipation methods for electronic components.

Efficient cooling of electronic components is influenced by the principles of heat transfer and fluid mechanics. Cooling electrical devices means controlling the operating temperature of electronic equipment to ensure stability and safety, involving heat dissipation, materials, and more. Currently, the main cooling methods include natural cooling, forced cooling, liquid cooling, refrigeration, thermal conduction, and heat pipe technology.

1. Natural Cooling Method

Natural cooling occurs under natural conditions without external auxiliary energy, using conduction, convection, and radiation to dissipate heat from components to the surrounding environment. Among these mechanisms, natural convection is the most commonly applied.

This method is mainly used for low-power devices with low temperature-control requirements and low heat-flux density. It can also be applied to sealed or densely assembled devices when no additional cooling technology is required.

When heat dissipation requirements are low, conduction or radiation can be enhanced through structural optimization to improve natural convection and strengthen overall system cooling performance.

2. Forced Cooling Method

Forced cooling accelerates airflow around electronic components using fans or similar devices, removing heat effectively. This method is simple, convenient, and offers significant cooling performance.

It can be applied when sufficient space is available for airflow or for installing cooling structures. Convective heat transfer can be improved by increasing the total heat-dissipation area and enhancing the convective heat-transfer coefficient.

Fin structures are widely used to enlarge surface area and strengthen heat transfer. For high-power devices, turbulence-enhancing structures may be added to alter the flow field over the heat sink and improve heat exchange efficiency.

3. Liquid Cooling Method

Liquid cooling dissipates heat from chips and chip modules and can be classified into direct and indirect cooling.

Indirect liquid cooling uses intermediate media—such as liquid modules, heat-transfer modules, spray modules, or liquid-cooled substrates—to transfer heat from electronic components.

Direct liquid cooling (immersion cooling) allows coolant to be in direct contact with electronic components. The coolant absorbs and removes heat efficiently. This method is mainly used for devices with high heat-flux density or those operating in high-temperature environments.

4. Refrigeration-Based Cooling Methods

Refrigeration-based cooling includes refrigerant phase-change cooling and Peltier cooling, depending on the application environment.

Refrigerant Phase-Change Cooling

This method uses refrigerant phase change to absorb large amounts of heat, making it suitable for specific cooling scenarios. It includes pool boiling and flow boiling types. Cryogenic technologies can also be applied in high-power computing systems, offering higher cycle efficiency, a wide operating temperature range, and compact system design.

Peltier Cooling (Thermoelectric Cooling)

Peltier cooling offers advantages such as compact size, ease of installation, and high reliability. It utilizes the Peltier effect of semiconductor materials—heat is absorbed at one junction and released at another.

Although it provides negative thermal resistance, its higher cost and lower efficiency limit its use to compact systems with modest cooling requirements. Typical performance: cooling temperature ≤100°C; cooling load ≤300W.

5. Thermal Conduction (Energy Transfer)

Thermal conduction transfers heat from electronic components to another environment using heat-transfer elements. As electronic circuits become more integrated and power density increases while device size shrinks, cooling structures must maintain high thermal performance.

Heat pipe technology offers excellent thermal conductivity, good isothermal performance, variable heat-flux adaptability, and fast response. It is widely used in electronic equipment, component cooling, and semiconductor applications. Heat pipe design depends on factors such as gravity, external forces, material selection, manufacturing processes, and cleanliness. Strict quality control and temperature monitoring are essential.

6. Heat Pipe Cooling

A typical heat pipe consists of a shell, a porous wick structure, and working fluid. In a vacuum environment, the working fluid absorbs heat at the evaporator section and vaporizes. Driven by a small pressure difference, vapor flows to the condenser, releases latent heat, and condenses. The condensate returns to the evaporator via capillary action in the wick.

This continuous cycle transfers heat efficiently from the evaporator to the condenser.

Heat pipes can transfer large amounts of heat with minimal temperature difference—their effective thermal conductivity is hundreds of times greater than that of copper, earning them the name “near-superconductive heat conductors.” However, heat pipes have a maximum heat-transfer limit. When heat input exceeds this limit, all working fluid vaporizes, the thermal cycle stops, and the heat pipe fails.