两相混合式换热器瞬态工况热力学模型及应用

Thermodynamic model of two-phase mixed heat exchanger under transient conditions and its application

换热器是能量系统的重要设备,两相混合式混热器作为换热器内部能量交换比较复杂的设备,研究其能量分布具有重要意义。通过对混合式换热器进行了研究,建立了两相混合式换热器的热力学模型,相对以往的稳态研究加入了瞬态项的影响。运用所建模型,对某除氧器进行模拟,得到了其瞬态工况的能量分布,为了验证瞬态模型的计算结果,采用稳态模型进行了计算,并与瞬态结果进行了对比,差别主要在工质蓄热火用上,并给出了影响蓄热火用的主要因素。

Heat exchanger is an important equipment in energy system,and mixed heat exchanger is a very complex equipment during changing energy.It＇s a great use to study the energy distribution in it.In this paper,a two-phase thermodynamic model was established.Comparing to the past research in the steady state,the influence of a transient section was added.A deaerator was simulated using the model;the energy distribution under steady state and transient state was obtained.Then the thermodynamic energy and exergy loss distribution was analyzed in details,and an analysis was made to obtain the main causes of the gap and the impact of different parameters,hoping to improve the study of save energy theory for energy systems.