The HVLS story: In 1998, dairy farmers were looking for a way to cool their cows to reduce heat stress. Air conditioning was too expensive and it was impossible to run the ductwork in the barns. Small barn fans helped, but didn't cover a wide enough area, consumed excessive and costly energy, and required ongoing maintenance. The engineers at Mechanization Systems Company (now known as MacroAir) created a huge fan with blades spinning 24' instead of the typical 2'. And to create a gentle breeze, the fan speed was a fraction of the speed of small fans.
To the average person, a fan blade may
seem like a simple design. But it
actactually takes a great deal of planning and design knowledge to fabricate a fan
blade that moves air as cleanly and efficiently as the MacroAir models. The
engineering department at MacroAir took several years to perfect the HVLS fan,
which currently integrates aerodynamic technology designed by NASA for airplane
In 2006, after studying the basic
aerodynamical design, MacroAir engineers decided they could make the fan
technology even more efficient by redesigning the fan blades and using
aerodynamic technology. The redesign led by Walter Boyd, MacroAir co-founder,
led to the development of the WhisperFoil fan, equipped with six airplane wing
shaped blades made using aerodynamical technology engineered by NASA. Walter is a race car driver. He was aware that the airfoil shaped wing on
the back of race cars produced downward force to help increase traction for the
cars, even at relatively low speeds.
Airfoils have a thicker, rounded leading edge (front), and a thinner
trailing edge (back). The top and of an
airfoil shape are curved, with more curve in the top and less curve on the
bottom. Air flows faster over the top
than the bottom. That means there is
less air pressure above than beneath the airfoil shaped wing, which causes
lift. With a fan, this shape causes the
air to go down. But how efficiently this
process works is where the science and engineering comes in. MacroAir’s folks studied the blade’s shape,
size, length, the angle of attack, the speed of the fan and the density of the
air in order to perfect the blade design.
For example, MacroAir understands that airplanes designed for low speed
flight have a different airfoil shape than airplanes designed for faster
speed. They realize that longer, more
slender wings like those on a sailplane are much more efficient at creating
lift without very much drag. And straight
wings are found mostly on smaller, lower speed planes. All these considerations can be seen in the
long, slender, straight, airfoil-shaped blades that make MacroAir fans the
premium HVLS design.
For information on HVLS Fans please call Gulf Coast Dock and Door (985) 246-1550 or Email us!