how does the gas turbine work?

Question

in reciprocating engines the combustion results in horsepower.This is achieved by in the cylinders rotating the crankshaft, flywheel. How do turbines produce power

Answer 1

Go to this link:

http://www.howstuffworks.com/turbine.htm

Answer 2

Gas turbines are described thermodynamically by the Brayton cycle, in which air is compressed isentropically, combustion occurs at constant pressure, and expansion over the turbine occurs isentropically back to the starting pressure.

In practice, friction and turbulence cause:
a) non-isentropic compression - for a given overall pressure ratio, the compressor delivery temperature is higher than ideal.
b) non-isentropic expansion - although the turbine temperature drop necessary to drive the compressor is unaffected, the associated pressure ratio is greater, which decreases the expansion available to provide useful work.
c) pressure losses in the air intake, combustor and exhaust - reduces the expansion available to provide useful work.

As with all cyclic heat engines, higher combustion temperature means greater efficiency. The limiting factor is the ability of the steel, ceramic, or other materials that make up the engine to withstand heat and pressure. Considerable engineering goes into keeping the turbine parts cool. Most turbines also try to recover exhaust heat, which otherwise is wasted energy. Recuperators are heat exchangers that pass exhaust heat to the compressed air, prior to combustion. Combined cycle designs pass waste heat to steam turbine systems. And combined heat and power (co-generation) uses waste heat for hot water production.

Mechanically, gas turbines can be considerably less complex than internal combustion piston engines. Simple turbines might have one moving part: the shaft/compressor/turbine/alternator-rotor assembly (see image above), not counting the fuel system.

More sophisticated turbines (such as those found in modern jet engines) may have multiple shafts (spools), hundreds of turbine blades, movable stator blades, and a vast system of complex piping, combustors and heat exchangers.

As a general rule, the smaller the engine the higher the rotation rate of the shaft(s) needs to be to maintain tip speed. It turns out that tip speed determines the maximum pressure that can be gained in the turbine independent of size of the engine. jet engines operate around 10,000 rpm and micro turbines around 100,000 rpm.

Thrust bearings and journal bearings are a critical part of design. Traditionally, they have been hydrodynamic oil bearings, or oil-cooled ball bearings. This is giving way to foil bearings, which have become common place in micro turbines and APU's (auxiliary power units.)

You could get more information from the link below...

Answer 3

a turbine is a device that transform continuous high pressure flow to continuous low pressure flow.
low pressure inlet air comes from an inline compressor to the combustion chamber where mixed with combustible where the temperature increase as well the pressure, the high pressure gas lets the turbine turns, part of the torque is transferred to the compressor and the most is extra and ready for use

Answer 4

a jet engine blows fire onto a fan the fan turns