Abstract: A method of air-conditioning a space, including: delivering pressurized air into the space from a hollow body connected to a source of pressurized air, elastically flexing an elastic flap of the hollow body under an action of the pressurized air such that a passage section at the flap varies in size as a difference in pressure between the inside of the hollow body and the space being air-conditioned varies, automatically modulating a delivery speed of the pressurized air into the space so as to avoid unpleasant effects on occupants in the space being air-conditioned, reducing pressure losses at the delivery outlet of the hollow body, and reducing energy consumption required to air-condition the space.