内螺旋盘管冷凝器动态特性数值模拟

一种用于海水冰浆机的内螺旋盘管冷凝器可以显著强化传热和减小换热器体积,为了研究这种换热器的动态工作过程建立了分区、分流型的适时动态分布参数模型,模型考虑了流体的适时物性参数、湿区含液量、流动压力损失以及管壁蓄热等影响因素,采用显式方程组,求解速度快,并且在计算过程中可根据制冷剂状态从所建立的物性数据库中适时获取物性参数.模拟计算结果与实验吻合较好,表明该模型可以预测冷凝器启动过程的动态特性以及冷凝管长度与直径、冷却水流速与入口温度因素对冷凝器动态换热过程的影响.

Numerical Simulation on Dynamic Characteristic of Inner Spiral coil Condenser

A kind of inner spiral coil condenser which could obviously enhance heat transfer and reduce the volume for sea ice slurry generator was investigated. A dynamic model of transient distributed parameters was set Up with divided zones and divided flow patterns in order to study the dynamical modeling on heat-transfer process of heat exchange, and during the setting up of the model an explicit type equation group was adopted for expediting resolution speed and some specific details were also taken into account, such as fluid transient physical property parameters, liquid content in wet zones, flow pressure losses and tube wall heat accumulation, etc. In the process of simulation, a computer can automatically check and select corresponding physical property parameters from an established database on the basis of a refrigerant condition. Furthermore, simulation results is in wen agree- ment with the experiment, and it is found that the model can be used to predict the dynamic characteristic of condenser during start-up process, and the influence of the design length and diameter of condenser pipe, inlet velocity and temperature of cooling water, etc. on dynamic heat transfer process of condenser.