HAT循环饱和器工质(火用)计算分析及(火用)效率

饱和器是HAT循环中的关键部件,对其性能的认识关系到整个系统的性能分析。运用的方法,计算了饱和器工质湿空气和水的值,分析了不同参考点的温度和湿度对值的影响规律,以及物理和化学扩散随湿空气温度的变化情况。通过建立饱和器平衡模型,采用了目的效率作为饱和器效率。计算结果表明：湿空气值随参考点的温度和湿度变化规律为：先减小,直到最低点为零,然后不断增加,值始终大于(等于)零,并且与参考点参数差距越大,值越大。当湿空气温度增加,物理所占比重减少,而化学扩散的比重增加,在到达一定温度后,化学大于物理。

Exergy Computational Analysis of the Working Medium of a Saturator and the Exergy Efficiency of the Saturator in a HAT Cycle

A saturator is the key component of a humid air turbine(HAT) cycle.Knowledge about its performance has a direct bearing on the performance analysis of the system as a whole.The authors have calculated the exergy of the saturator working-medium,i.e.humid air and water and analyzed the law governing the influence of temperature and humidity at difference reference points on exergy as well as the variation of physical exergy and chemical diffusion exergy with a change in humid air temperature.Through the establishment of an exergy equilibrium model for the saturator a target-exergy efficiency has been employed to serve as the exergy efficiency of the saturator.From the calculation results the law governing the variation of humid air exergy magnitude with a change in temperature and humidity at reference points has been identified as follows: the exergy of the humid air first decreases until a minimum value of zero is reached,then there is a continuous rise in value,the exergy magnitude being always greater than(or equal to) zero.Moreover,the greater the difference from the reference-point parameters,the greater will be the exergy magnitude.With an increase in humid air temperature the share taken up by the physical exergy decreases,while that taken up by the chemical diffusion exergy increases.When a certain temperature has been reached,the chemical diffusion exergy will be greater than the physical one.