Düsenauslasses

Düsenauslasses is a term used in German-language technical literature to denote the exit section of a nozzle, the point at which the conditioned fluid or gas leaves the nozzle assembly into the surrounding environment. The word combines Düse (nozzle) and Auslass (outlet); in plural form it is Düsenauslasses. In engineering, the nozzle outlet is a critical control element for jet characteristics such as exit velocity, static pressure, and mass flow.

Different geometries give rise to different performance regimes. A convergent nozzle accelerates flow by reducing cross-section and is used when upstream pressure limits the achievable exit Mach number. A divergent nozzle, with an expanding cross-section, is designed to produce or sustain supersonic exhaust under suitable pressure ratios. A convergent-divergent, or de Laval nozzle, uses a throat to accelerate flow to Mach 1 and then expands in the divergent section to reach higher Mach numbers.

Materials and thermal protection are important, as nozzle outlets operate at high temperatures and may experience erosion, heat transfer, or chemical attack from the exhaust. The design often involves optimizing the expansion ratio, contour, and mating with the rest of the propulsion or process system to minimize losses and audible noise.

Applications span rocket and jet propulsion, gas turbines, and industrial spray or cooling systems, where controlled jet exit conditions determine thrust, efficiency, or spray characteristics. The concept has roots in early jet propulsion research, with the de Laval nozzle as a foundational example.

See also: nozzle, thrust equation, De Laval nozzle, exhaust outlet.