reaction turbine

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Related to reaction turbine: Francis turbine

reaction turbine

[rē′ak·shən ‚tər·bən]
(mechanical engineering)
A power-generation prime mover utilizing the steady-flow principle of fluid acceleration, where nozzles are mounted on the moving element.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Reaction Turbine


a turbine in which a substantial part of the potential energy in the working fluid (the fluid head or the thermal gradient of a gas or steam) is converted into mechanical work in the blade passages of a runner that have the configuration of a jet nozzle.

In modern turbines the peripheral force that turns the runner is created by the total effect of two forces: the force that develops when the direction of flow of the working fluid is changed in the blade passages (the impulse principle) and the reactive force that develops when the velocity of the working fluid is increased (the reaction principle). The ratio of the amount of energy that is converted in the rotating blades of a turbine to the total amount of energy used is called the degree of reaction p. When ρ = 1, a turbine is said to be completely reactive, and when ρ = 0, the turbine is called an impulse turbine. In practice, all turbines operate with some degree of reaction, but only those in which not less than 50 percent of the total potential energy in the working fluid is converted by the reaction principle, that is, in which ρ ≥ ½, are conventionally called reaction turbines.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

Reaction turbine

A power-generation prime mover utilizing the steady-flow principle of fluid acceleration, where nozzles are mounted on the moving element. The rotor is turned by the reaction of the issuing fluid jet and is utilized in varying degrees in steam, gas, and hydraulic turbines. All turbines contain nozzles; the distinction between the impulse and reaction principles rests in the fact that impulse turbines use only stationary nozzles, while reaction turbines must incorporate moving nozzles. See Impulse turbine, Prime mover

McGraw-Hill Concise Encyclopedia of Engineering. © 2002 by The McGraw-Hill Companies, Inc.

reaction turbine

reaction turbineclick for a larger image
A type of turbine in which the stator vane and the rotor are arranged in such a way that the entire pressure drop takes place between the rotor blades, which have convergent passages in the direction of flow. The nozzle-guide vanes only guide the flow for the rotors. The turbine is driven by the reaction force resulting from the acceleration of gases through the converging blade passage and, hence, the name.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved
References in periodicals archive ?
In the early 19th century, several inventors, including the steam engine builders James Watt and Richard Trevithick in England and Oliver Evans in America, experimented with steam reaction turbines of the Hero type, but without much success.
There are two different types of turbines in hydropower plants: reaction turbines (Francis, Kaplan) and impulse turbines (Pelton).
They begin with the operating characteristics, design features, reliability considerations, and maintenance protocols of steam turbines, and cover stationery components and casings, bearings for mechanical drive turbines, rotors for impulse and reaction turbines, turbine blade design, turbine components (such as the lubrication system, governors and control systems), couplings and coupling considerations, dynamic technology, diagrams for steam turbine blades, reaction and impulse-type steam engines, transmission elements for high-speed turbomachinery, shortcut graphical methods for turbines selection, selection methods for multi stage steam engines, and re-rating, upgrading, and modifying steam engines across a life of the machine.