| Re: the jet propulsion with closed combustion type Under some condition, when the pressure after compression is pretty high, reducing the pressure by combustion in some extent, the efficiency reduce a little, meanwhile the temperature before turbine reduce much, I state a example:
Set the temperature of outside air: 300K, k=1.4, set the pressure after compression/before compression α=7, the pressure after combustion/before combustion β=7.5, thus the temperature turbine 2206K, efficiency:η=60.2%; k=1.4, α=7, β=7, the temperature turbine 2100K, η=59.6%; k=1.4, α=7, β=6.5, the temperature turbine 1992K, η=58.9%; k=1.4, α=7, β=6, the temperature turbine1881K, η=58.2%; I change β by change in the volume proportion of fresh gas in each time or change of the concentration of fuel a little. In this example, η is reduced by 3%, the temperature before turbine decrease 400K.
The method also is used to calculate the temperature of each course. This example just remind that these is a phenomenon. The datas to some parameters may not precise, actually they change in normal and very high temperature.Here I assume them unvaried. after all it is a good reference for you.
Last edited by qumf; 04-19-2007 at 04:36 AM.
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