jet engine energy subsystems

[daniv]

hi
Does any one knows (in ROM figure or percentage) how much of the total energy input in a “common” jet engine is consumed by the compressor, turbine efficiency, heat looses to surrounding and net trust.

 

[orka]

hi daniv,

May be a couple of figures can be helpful.
Generators driven by gasmotors output approx. 30% of the energy that is supplied to the motor under the form of gas.

Gasturbines put about 30-35% of the supplied energy on the main shaft. Approx. 50-60% leaves the turbine as warm exhaust gas. Some extra losses such as cooing of the oil circuitry, heat radiation, ventilatie and the like can be estimated between 15-20%.
Exhaust gases have a temperature of about 400-600°C and contain between 15-18% of oxigen, wihich makes these reusable as burner ar for a second incineration process. For instance, in waste incineration were the tend is to burn "oxygen poor", it can be very profitable to construct -- a set of a gas turbine,
-a heat exchanger to cool the exhaust gases at one side and to overheat steam at the other side
-the incinerator that generates the steam
The overall efficiency can be pretty high and as a second consequence, the exhaust gases of the turbine, generally rich of NOx will paas through the gas purifying and DeNOx system that handles the waste incinerator gases.

Friendly greetings
orka