Which fan blade type produces the highest air velocity?

The option identified as the correct answer, forward curved blades, produces the highest air velocity among various fan blade types due to their design. Forward curved blades are shaped to effectively gather air at the leading edge and accelerate it as it passes through the fan. This curvature allows the blade to impart a significant amount of energy to the air, leading to higher velocities in the airflow as it exits the fan.

In contrast, other fan blade types have different designs suited for specific applications. Air foil blades are efficient and designed to minimize drag, which makes them ideal for high-efficiency applications but doesn’t maximize air velocity in the same way. Backward inclined blades are effective for handling varying loads and are typically used in systems requiring a good balance of efficiency and capacity, but they do not produce the same high air velocities. Radial blades, while capable of moving larger volumes of air, often do so at lower velocities compared to forward curved blades due to their straight design and the way they interact with airflow.

Thus, the unique shape and operational characteristics of forward curved blades allow them to achieve the highest air velocity, making them suitable for applications requiring fast air movement.