肋片管表冷器湿工况动态数学模型及仿真

Dynamic mathematical model and simulation of fin-tube cooling coils on wet conditions

利用分段集总参数法建立了肋片管表冷器在湿工况下的动态数学模型,将模型的微分方程转换为以表冷器各出口参数为状态变量的状态方程,对表冷器动态数学模型进行了直接求解,得到了肋片管表冷器各微元段水侧温度和空气侧温湿度随时间的变化关系,分析了表冷器在湿工况下达到稳态时各微元段的换热情况,以及流体入口温度和流速扰量对表冷器换热量的影响。结果表明,空气侧流速扰量对表冷器换热量的影响最大,随空气流速的增大,换热量增加的速度将减小。

Establishes a dynamic mathematical model of fin-tube cooling coil on wet conditions using the sub-lumped parameter method.Through converting the differential equation of the coil model into the state equation in which the state variables are the outlet parameters,the dynamic model is solved directly.Obtains the function expressions of water temperature,air temperature and humidity of all sub-elements of fin-tube cooling coil.Analyses the heat transfer of sub-elements on wet condition in the steady state,and the influences of the fluctuation of inlet temperature and air velocity on the heat transfer of cooling coil.The results show that the fluctuation of air velocity has the greatest impact on the heat transfer,and increasing rate of heat transfer will decrease with increase of air velocity.