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fluid mechanics
- In fluid mechanics: Compressible flow in gases
  …a gas flows through a nozzle or through a shock front (see below), the flow, though adiabatic, may not be reversible in the thermodynamic sense. Thus the entropy of the gas is not necessarily constant in such flow, and as a consequence the application of equation (120) is open to…
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steam
- In turbine: Principal components
  …steam (it also accommodates fixed nozzle passages or stator vanes through which the steam is accelerated before being directed against and through the rotor blading), (3) the speed-regulating mechanism, and (4) the support system, which includes the lubrication system for the bearings that support the rotor and also absorb any…
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water
- In turbine: Impulse turbines
  …water through a carefully shaped nozzle. The jet, discharged into air, is directed onto curved buckets fixed on the periphery of the runner to extract the water energy and convert it to useful work.
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jet engines
- In jet engine: Low-bypass turbofans and turbojets
  …with an afterburner, the exhaust nozzle must have a variable throat area to accommodate the large variations in volumetric flow rate between the very hot exhaust stream from the operating afterburner and the cooler airstream discharged from the engine when the afterburner is not in use. Engines intended for supersonic…
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rockets
- In rocket: Solid-rocket motors
  The principal requirement for a nozzle, common to both solids and liquids, is that it be able to produce a supersonic flow of the exhaust gas from the combustion chamber pressure to an exterior pressure (or thereabouts), a function that is accomplished by proper contouring and sizing of the conduit.…
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