Why Do Most Ceiling Fans in India have 3 Blades
Electric fans can have 3-4-5 – any number of blades but why do fans in India only stick with 3 blades?
The primary purpose of an electric fan is to create air flow. A good fan can do that with minimal noise. A fan is also designed according to the conditions of the operating environment and the required level of air delivery.
In India, fans are usually a stand-alone appliance to generate cooling comfort. Also, India is a tropical country with most areas having high temperatures. Hence, users require a higher quantum of air to create a cooling effect.
As per research, three turns out to be the optimum number of blades for air movement and efficiency. Adding more blades does not improve performance and may actually make it worse by increasing the aerodynamic drag on the motor.
Technologically, the lesser the number of blades, higher the air delivery. This is one of the reasons why industrial fans (like wind turbines) usually only have two or three blades. They can go faster and move more air. The resulting noise is not much of a concern in those areas of operation.
However, for domestic ceiling fans, three blades turn out to be optimal for air delivery and cooling comfort. The noise level is also suitable for homes.
With higher number of blades, the fan tends to be slower in speed and thus quieter but circulates less air. Additional blades increase the drag on a ceiling fan's motor and slow it down.
The shape of the blades also matters.Luminous ceiling fans have aerodynamically balanced blades as the air flow is top-down.
In US and Canada, the primary requirement for the ceiling fan is to supplement the air-conditioner in summers. In winter, many of these fans with a reverse switch can be flipped to turn the direction of the rotation. This makes it possible to draw cold air and circulate warm air from the heaters that are usually lined up against the walls. Thus, the fans there are designed for a different purpose and may have four or five blades.
In India, four or five bladed ceiling fans can help complement your room aesthetics. The Luminous designer product range features fans with more than three blades and are available in several different patterns and colors.
For economy fans, most people think that more the blades, better the cooling. Well, it turns out that the opposite is true.