ABSTRACT

A combined gas power cycle with humidification has been investigated using the advanced exergy analysis. The combustion chamber and humidifier were found to be the components with the largest exergy destruction. For a prescribed overall power generation, the exergy destruction at the combustion chamber increased, while that at the humidifier decreased when the humidification ratio at the bottoming cycle was increased. However, most of the irreversibility generation at these components was shown to be unavoidable. The topping cycle turbine and compressor were revealed to be the components with the largest endogenous and avoidable irreversibility generation. This means that there is a real potential of improving the overall performance of the cycle by improving the operation of these two components. The endogenous avoidable exergy destruction at the topping cycle turbine and compressor decreased monotonically when the humidification ratio, the combustion chamber exit temperature or the mass flowrate ratio between the bottoming and topping cycles were increased, and increased when the topping cycle pressure ratio was increased. On the other hand, varying the humidification ratio at the bottoming cycle from zero to one resulted in as much as 26% reduction of the irreversibility generation at the topping cycle turbine and compressor.

摘要

使用先进的（火用）分析研究了加湿的燃气循环。发现燃烧室和加湿器是最大的火用破坏成分。对于规定的总发电量，当增加底部循环的加湿比时，燃烧室的火用破坏增加，而加湿器的火用破坏减少。但是，在这些组件上大多数不可逆生成都是不可避免的。顶部循环涡轮机和压缩机被证明是产生最大内源性和可避免的不可逆性的组件。这意味着通过改善这两个组件的操作，确实存在改善循环整体性能的潜力。当加湿比，燃烧室出口温度或底部和顶部循环之间的质量流量比增加时，顶部循环涡轮机和压缩机的内源性可避免的火用破坏单调减少，并且当顶部循环压力比增加时，内源性可避免的火用破坏单调减小。另一方面，在底部循环中将加湿比从零改变为一个会导致顶部循环涡轮机和压缩机的不可逆性产生降低多达26％。