Delivering energy-saving air by "crawling" along the ceiling

The high ceiling space is comfortable.

On the other hand, to air-condition a large space, it is necessary to lay ducts in the ceiling to carry the air to the back of the room. Because these ducts are very large, it is difficult to realize high ceilings. Every day, facility engineers work hard to optimally design ducts to maximize space while ensuring comfort.

The idea behind "Coanda air conditioning" is to eliminate the need for ducts altogether.
Using the Coanda effect, a phenomenon in which wind is drawn to a surface, the smooth ceiling surface allows the wind to be blown far away without the need for ducts. However, this air conditioning/cooling system cannot be operated on low power. Cold air is heavy, and if the wind does not have enough force, it will fall down along the way and will not reach the back of the room. The inability to operate on low power is a major issue that must be resolved from the perspective of energy conservation.

That's why we developed the "Air-Soarer."
It uses wind pressure to automatically adjust the area from which the air comes out. Just like how water can reach a long distance when you crush the end of a garden hose, if the area from which the air comes out is smaller, even a weak wind can blow faster and reach a long distance. A weighted blade is attached to the air outlet, and when it is in high-speed mode, the wind pushes the opening open, and when it is in low-speed mode, the weight closes the blade.
This makes it possible to operate the fan at low power, reducing the amount of energy used for blowing air by 83% per year.

Simulation is a useful method for predicting the environment. However, there are few examples of analysis that show the details of where the air drawn into the ceiling by the Coanda effect separates and falls, making it difficult to reproduce. There was concern that these details could have a significant impact on the environment of the entire room. Therefore, in order to accurately grasp this behavior, we actually built a mock-up laboratory and carried out detailed environmental measurements.
What's important is how comfortable or uncomfortable people feel in an actual space. By conducting subject experiments under a variety of conditions, including seating location, gender, and age, and fine-tuning the equipment, we were able to develop a system that creates a highly comfortable air-conditioned space.

With the Air-Soarer we developed, it has become possible to simultaneously achieve a ductless high-ceilinged space and energy conservation. At Mitsubishi Jisho Design our MEP Engineering department, we value ideas for creating better spaces and pay close attention to the details when designing.