What types of fans do air-cooled engines typically use?

Air-cooled engines typically utilize centrifugal or axial-flow fans to facilitate effective cooling. Centrifugal fans generate airflow by drawing air in through the center and discharging it outward, creating higher pressure and an efficient flow of air across the engine components. This design is beneficial for cooling as it allows for better airflow management around hot engine parts.

Axial-flow fans, on the other hand, move air parallel to the shaft of the fan. These fans are designed to move large volumes of air at relatively low pressure and are often used in situations where maintaining a consistent cooling effect is necessary for engine performance. The efficiency of these types of fans is key to maintaining optimal operating temperatures in air-cooled engines, preventing overheating and ensuring reliability.

The other options do not pertain directly to fan types suitable for cooling air-cooled engines. Radiant and thermal options relate more to heat transfer concepts than to specific fan designs. Helical and spiral fans are not standard terminology associated with engine cooling, and exhaust or intake refers to air flow paths rather than specific fan types.