利用数值模拟方法研究了湍流状态( 雷诺数Re 变化范围为27900 ～41900) 下自支撑矩形缩放管换热器壳程内插入不同插入物( 圆环和折板) 后的传热性能与流动特性，并将壳程通道内插入圆环和折板后得到的结果与缩放管空管( 无插入物) 的结果做比较．结果表明: 插入物的加入引起了通道内流体的速度及温度分布变化，从而产生传热及流动特性的变化; 插入圆环和折板后壳侧的传热系数分别比缩放管空管时增加了16．69% ～24．32%和38．01%～46．74%; 在插入插入物后，传热系数增加的同时也引起了通道内压降的增大，与缩放管空管时比较，插入圆环和折板情况下压降增加的比例分别为74．02% ～89．50%和68．49%～87．16%; 插入折板后壳程通道内的综合传热性能最好，其次是插入圆环后，缩放管空管时最差．研究还发现，要提高换热器的传热性能，关键是要改善通道两侧缩放管处的传热性能，而从场协同角度对三者进行分析则发现，减小速度矢量与温度梯度矢量间的夹角是增强换热器传热性能的一个重要措施．

The shell- side heat transfer and flow characteristics of self- supported rectangular converging- diverging tubes with different inserts (torus and baffle plate) were numerically simulated in a turbulence state with the Rey-nolds number varying from 27900 to 41900,and the results were compared with those without inserts.It is found that the insertion of torus and baffle plate results in the variations of velocity and temperature distribution in the channel and consequently leads to different heat transfer and flow characteristics,that the shell- side heat transfer coefficients of the two enhanced tubes respectively increase by 16.69%～24.32% and 38.01%～46.74% after the insertion,with the associated pressure drop increments achieving 74.02%～89.50% and 68.49%～87.16%,respectively,and that the tube with baffle plate is of the best overall shell- side heat transfer performance,while the baseline is of the worst.Moreover,it is indicated that the key to the heat transfer enhancement of a heat exchanger is to improve the heat transfer of the converging- diverging tube on the two sides of the channel,and that,from the viewpoint of field synergy principle,the reduction of the average intersection angle between the velocity vector and the temperature gradient is one of the essential factors to enhance the heat transfer performance.