Triennale Milano
Windhunter® 1.6.S inserito in un campo di girandole, 2012 © Michele Boni 2022
Windhunter® 1.6.S inserito in un campo di girandole, 2012 © Michele Boni 2022

Unknown Air: a material to be rediscovered and explored

February 25 2022
A lifelong misunderstanding
As Dr. Ersilia Vaudo Scarpetta, curator of the 23rd International Exhibition reminds us, only a thin blue layer surrounding the earth separates us from the suffocating vacuum of space. This thin blue layer, the atmosphere and our home, is made up of the air that surrounds us, touching and nourishing us with oxygen from our first moment until death. At macroscale level, as climate change gathers place, there is a growing awareness of the relative smallness and ill-health of this thickness of air. Indeed, most nations have started trying to find ways to preserve it. But at microscale level, its invisibility, low density that makes it almost impalpable and its extreme mobility mean that for most of us air remains an intangible element, hard to control and hard to understand. Indeed, it is often associated with the void, the absent, the immaterial, the virtual, nothingness – all concepts that have nothing to do with its nature or characteristics. In short, air is a precious life companion that welcomes and accompanies us faithfully, but one that, all too often, we are blithely unaware of. The time has come to rediscover it.
Air: not just matter but a construction material Invisible, mobile, formless, almost weightless, air is nevertheless a material, much like earth, water and wood. Like these other materials, it is built up of substances and conditions. Air’s constituent substances vary in proportion and concentration, becoming more or less pure, dense, and light. Under certain circumstances, air can become opaque; in other conditions, if accelerated, it can temporarily become almost solid. If we are able to keep these variations under control, air can be used as a truly contemporary building material.
The air curtain as the foundational element of airflow structures Just as an artist works a block of marble to try to carve out a certain form, it is possible to sculpt air to obtain a certain spatial result, using it as a simple means of separation in lieu of a window or a door. Air can become a dividing element that takes the place of a wall or a roof, or even a set of separations, giving rise to enclosed envelopes and forming true architectures. In airflow structures, the basic structural element – which in classical architecture would be brick – corresponds to the air curtain.

Image of an air curtain, Transverse section © Prof. Francois Penot (LET ENSMA – Poitiers)
Air Architecture
Although unknown to the general public (in truth, even to many industry insiders), history is peppered with examples of systems that use air as a material to create protected spaces. Indeed, they may be considered their own separate group of architectures, with sub-groups of different families. Air Architecture families run from fill-in architecture to cloud architecture, fog architecture, natural wind architecture, artificial wind architecture, air greenhouse architecture, air bubble architecture, and air drop architecture.
Air, air, air!
Unlike in classical architecture, where the interior is separated from the exterior by a container made from a solid and opaque material (AIR/SOLID MATERIAL/AIR), or inflatable architecture in which the interior is separated from the exterior by a container made from light fabric (AIR/FABRIC/AIR), in these examples of Air Architecture the interior is separated from the exterior by a container made of air. In other words, in these architectures, the air that forms the outside environment is isolated from the air that forms the inside environment by walls of air, making them AIR/AIR/AIR.
The Air Architecture Manifesto. Doctoral thesis in architecture, co-tutorship between the Faculty of Architecture of Florence and the Université Paris 8, Michele Boni, Paris 19 12 2008
Aerodesign projects
I’ve been studying, observing and experimenting with air for some twenty-five years now, seeking to understand and use it both as a material for building and sculpting. Alongside my theoretical investigations, from an applied research point of view, by using air curtains to separate, wrap and sculpt space, I have created energetic, intermittent systems that achieve climatic, physical and biological separation. These ephemeral, weather-protected environments produce often unexpected features that go far beyond what standard spaces can achieve. During my research, I have performed thousands of CFD simulations, built dozens of models, prototypes and demonstrators, and performed hundreds of tests.

Meetings among the waves. 170 numbered and signed photographs, size 29.7 x 29.7 cm. Technique: drawing with air. Materials: air curtains, light elements, black light, 2020 © Michele Boni 2022
Frontières d’air® and Windhunter®
Is it possible to build a magical open-air space that is invisible yet protected from uncomfortable wind, that is, with characteristics similar to an indoor space? This question prompted me to explore this unique, fascinating and surprising material, developing systems that, through a set of air curtains, create energetic, interactive, and intermittent environmental architectural works. Frontières d’air® (1998-2008) was the first climatic separation system I developed, under the auspices of the ARIA Engineering srl start-up. Visually, it looks like a stylized cube, even if it has no solid walls. Under certain conditions, through an increase in internal pressure, the system offers wind protection, creating a space with climatic characteristics similar to an indoor environment. This intermittent energy architecture may be termed an example of Air Bubble Architecture. I have built a variety of prototypes in sizes ranging from 1.5m each side to over 4m.

Frontières d’air system® 4.0.S (4m side, 3.5m height), smoke test, 2008 © Michele Boni 2022
Windhunter® (2011-2016), a fully automated system that is a veritable dual generator of energy and comfort, is a subsequent development. When installed outdoors, it is capable of generating energy and ensuring effective protection from wind and weather by forming two opposite and symmetrical tornadoes capable of deflecting and decelerating wind. In reference to its hallmark shape, we may define this intermittent energy architecture as Airdrop Architecture. Even if invisible, the system produces climatic comfort approaching that of an interior. The only way to understand this is through tactile experience: you have to get in there and feel it on your own skin. It has many practical applications: protecting café and restaurant terraces/sports spaces/swimming pools/outdoor relaxation spaces/gardens and waiting places/yacht and cruise ship decks. I have developed a variety of prototypes in sizes ranging from 1.5m to 4m in diameter.
Windhunter®: CFD simulations showing the formation of a drop-shaped protected space, 2011 © Michele Boni 2022
Windhunter®: CFD simulations showing the formation of a drop-shaped protected space, 2011 © Michele Boni 2022
Windhunter®: CFD simulations showing the formation of a drop-shaped protected space, 2011 © Michele Boni 2022
Windhunter® 1.7.S (static version, diameter 1.7m/h. 1 m) in operation, inserted in a field consisting of ten rows of eight pinwheels/rows positioned on a 20 cm square chessboard, 2012 © Michele Boni 2022
Windhunter® 1.7.S (static version, diameter 1.7m/h. 1 m) in operation, inserted in a field consisting of ten rows of eight pinwheels/rows positioned on a 20 cm square chessboard, 2012 © Michele Boni 2022
Windhunter® 1.7.S (static version, diameter 1.7m/h. 1 m) in operation, inserted in a field consisting of ten rows of eight pinwheels/rows positioned on a 20 cm square chessboard, 2012 © Michele Boni 2022
Windhunter® 7.5.S (static version, diameter 7.5m/h. 3.0 m) operating diagram for marine applications, 2013 © Michele Boni 2022
Windhunter® 4.0.S (static version, diameter 4.0m/h. 3.0m) installed on the superyacht Ketos (Rossinavi shipyard), 2013 © Michele Boni 2022
Windhunter® 4.0.S (static version, diameter 4.0m/h. 3.0m) installed on the superyacht Ketos (Rossinavi shipyard), 2013 © Michele Boni 2022
Windhunter® 1.3.M (mobile version diameter 1.3m/h. 0.9m) in operation, inserted in a field consisting of ten rows of eight pinwheels/rows positioned on a 20 cm square chessboard, 2016 © Michele Boni 2022
Windhunter® 1.3.M (mobile version diameter 1.3m/h. 0.9m) in operation, inserted in a field consisting of ten rows of eight pinwheels/rows positioned on a 20 cm square chessboard, 2016 © Michele Boni 2022
Purified Air Visor® All humans can potentially fall victim to polluted environments and pandemic viruses, Covid 19 being a case in point. Today’s most commonly-used solutions are classic fabric masks which, however, have a number of limitations: they are uncomfortable, make you sweat, hinder breathing, hide people’s mouths and smiles, hamper conversation and communication, provide no protection when eating or drinking, and cause issues for glasses-wearers, etc.. 
The Purified Air Visor® (2020) is an innovative item of PPE (Personal Protective Equipment) developed at Visionairlab Srl, a start-up I founded with engineer Luigi Spedini. In addition to effectively responding to both problems, eliminating the drawbacks of current solutions, it is a veritable connected wearable (IoT), an invisible system capable of blocking smog and pathogens by providing a continuous volume of pure air without having to wear unsightly, bulky or annoying protective systems. Thanks to fans and a filtering system, the Purified Air Visor separates the user from pathogens and/or pollutants, ensuring a volume of purified air that guarantees freedom of movement and socialization in safety, regardless of time or place.
Purified Air Visor® © Visionair Lab 2022
Purified Air Visor®: wind tunnel testing © Visionair Lab 2022
Air curtain operation diagram
The visor generates a barrier (represented here by smoke), separating off the space and protecting the user from pathogens and pollution
The air curtain creates an invisible barrier, separating off the space and protecting the user from pathogens and pollutants (represented here by horizontal lines of smoke)
Credits
Bibliography
The Air Architecture Manifesto. Doctoral thesis in architecture, co-tutorship between the Faculty of Architecture of Florence and the Université Paris 8, Michele Boni, Paris 19 12 2008.
ComfortBubble, Michele Boni, in AIR, John Knetchel, MIT Press, 2008, USA. 
European Patent no. EP0940526A1 (1998).
M Boni, L’architecture de la bulle d’air, Les Presses du Réel; Dijon, 2019.
European Patent no. EP12815807.8 (2014)/Chinese Patent no. 2012800664961 (2014)/US Patent no. 14362295 (2014).
Michele Boni, L’architecture de la bulle d’air, Les presses du réel, Dijon, 2019.
Michele Boni, Habiter l’air, Collection Alternatives, Editions Gallimard, Paris, 2020.
Italian patent application No. 102020000029870 dated 04 12 2020.