一次表面换热器瞬态响应特性的数值模拟

根据一次表面热交换器（PSHE）的结构和流动特点，利用能量守恒定律，导出它的瞬态温度变化物理模型和数学方程式.研究工作流体温度和流量发生阶跃变化时PSHE出口温度的响应特性，分析指出一次表面换热器板片各几何参数以及通道形状对其温度响应特性的影响次序是：板片厚度δ最强，宽度W和数目n次之，波纹通道形状最弱.比较研究表明，由于PSHE的固体壁面时间常数远小于板翅式和管壳式换热器，因此这种轻质结构换热器的响应特性明显优于常规热交换器，非常适用于那些要求工况经常变动、能够提供的场地和空间又十分有限的化工联合装置.

Numerical simulation of dynamic response for primary surface heat exchanger

Based on the conservation law of energy and on the characteristics of the structure and flow of the primary surface heat exchanger（PSHE），a physical model and corresponding mathematical equations of transient temperature are presented.The research on the response characteristics of the PSHE in different conditions，in which the temperature and mass of hot gas and cold air changed quickly，was carried out.The influence of slab geometrical parameters on the temperature response of the PSHE was found to be in decreasing order：first thickness δ of corrugated heat transfer slabs，second width W and number n，and third shape of corrugated channels.The comparisons showed that the low-mass PSHE has much more advantages in terms of dynamic characteristics than traditional heat exchangers，because the time constant of the PSHE solid wall was much smaller than that of pipe-shell and plate-fin heat exchangers.It is fit for application to the chemical complex that requires frequent change of operation conditions and has limited area and space.