The ideal cycle heat efficiency used nowadays is affected by the relative internal efficiency so it can't reflect the operation economic state of thermal system of steam turbine.

目前采用的汽轮机理想循环热效率受到相对内效率影响而不能准确反映汽轮机热力系统运行经济状态。

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Thermal efficiency is how much of the potential heat energy of the fuel used is actually returned as work at the wheels.

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