What are bladeless fans?
From Superfan, India’s first super energy efficient ceiling fan
Bladeless fans are the new buzzwords in the space cooling market. The real question is, what is the purpose of these fans. Let us review the performance of bladeless fans in this blog.
How do bladeless fans work?
Bladeless fans actually have blades that are fitted in the base of the fan but give an illusion of being bladeless by directing the air hollow tube. Similar to currently available super energy-efficient ceiling fans, the bladeless fans use BLDC motors. The air is propelled in through the slits in the base and pushed through the hollow tube.
To increase the air pressure, the slit opening at the top end is narrower than the bottom slits. The curvature of the tube also assists in pushing the air outside. The assistance comes from the principle of entrainment, which increases the airflow by multiple times .
Figure – Air movement in bladeless fans
Performance of bladeless fans
Bladeless fans are available in all variations like pedestal fans, wall mount fans, box fans, table fans, and ceiling fans. The bladeless fans have uniform airflow due to entrainment but overall airflow is far less than ceiling fans with blades. A 300 mm bladeless ceiling fan pushes 125 CMM of air on the person below. Studies have proven that this air from the bladeless fans is very noisy and hazardous to human health [2-3]. When increasing the performance of bladeless fans, tested through various experiments, the results always increased the noise level .
On the point of energy efficiency, bladeless fans consume 65W for delivering 130CMM of air. Also, there are no energy-efficiency regulatory standards for these fans in India.
For the ones, who prefer aesthetics and novelty, bladeless fans are good. If one prefers energy efficiency, sustainability, and more air over a larger area, then conventional fans and super energy-efficient fans are the way to go.
- Jafari, M., Afshin, H., Farhanieh, B., & Bozorgasareh, H. (2016). Experimental and Numerical Investigation of a 60 cm Diameter Bladeless.
- Jafari, Mohammad & Afshin, Hossein & Farhanieh, Bijan & Bozorgasareh, Hamidreza. (2015). Numerical Aerodynamic Evaluation and Noise Investigation of a Bladeless Fan. Journal of Applied Fluid Mechanics. Pg no 8.