What is a Cooling Fan?
In the RC (radio control) industry, a cooling fan is a device used to dissipate heat generated by electronic components, particularly in high-performance RC vehicles such as cars, drones, boats, and airplanes. These fans are typically mounted on heat sinks or directly on electronic components such as motors, ESCs (Electronic Speed Controllers), and even batteries to help prevent overheating during operation.

How Cooling Fans Work:

1. Heat Dissipation: When electronic components operate, they generate heat due to resistance and inefficiencies in the electrical circuits. This heat can build up and potentially damage the components or degrade their performance over time. Cooling fans work by blowing air over the surface of the component or heat sink, which helps to dissipate heat into the surrounding environment.

2. Airflow: The fan draws in cooler air from its surroundings and directs it over the surface of the heat sink or electronic component. As the air passes over the surface, it absorbs heat and becomes warmer. The warm air is then expelled out of the vehicle, allowing cooler air to take its place and continue the cooling process.

3. Thermal Management: By continuously circulating air and facilitating heat transfer, cooling fans aid in maintaining the operating temperature of critical components within safe limits. This helps prevent thermal throttling, where components reduce their performance to prevent overheating, and ensures optimal performance and longevity of the RC vehicle.

4. Performance Enhancement: In high-performance RC vehicles, such as those used in racing or aerobatics, maintaining low operating temperatures is essential for maximizing power output and maintaining consistent performance throughout the race or flight. Cooling fans play a crucial role in achieving and sustaining these optimal operating temperatures.

HOBBYWING University -- Understanding Cooling Fans: 
Function and Applications in Electronic Circuits