Abstract: An air introduction nozzle for high pressure-ventilated spaces has a substantially low-cylindrical structure and a centrally located air inlet space with a cylinder shell, which is provided with openings and is radially cylindrically surrounded by at least two air expansion spaces, filled with an air-permeable material. The air expansion spaces are separated from one another by cylinder shells provided with openings. The air is discharged from the nozzle through openings of the outermost cylinder shell enclosing the at least two air expansion spaces.

Abstract: A mixing system should, while effecting a homogeneous mixing with a low loss of pressure, have a short intermixing distance. The mixing system contains mixing elements disposed in a flow channel and have mixing blades disposed around a respective central axis. Adjacent mixing blades each have an overlap in their plane of projection to the normal plane of the central axis. An injection location for supplying a reaction medium is connected upstream from some or all of the mixing elements. The injection location is dimensioned such that the reaction medium, at its discharge from the injection location, has a discharge velocity that is increased by an excess factor with regard to the flow medium inside the flow channel. The mixing elements are dimensioned such that the quotient of the degree of overlap of adjacent mixing blades (in percent) and of the excess factor ranges from 0.1 to 5.