摘要
通过有限元软件计算了单管式螺旋管热交换器的内部流场和温度场,探讨了管程入口介质流量、介质温度以及螺旋管圈数对其换热效率的影响。结果表明,螺旋管热交换器的换热效率明显优于直管式热交换器,螺旋管圈数对换热效率并无明显的影响,但会显著地增加管程的沿程压力降;壳-管之间的换热主要发生在管程的入口附近,因此可进一步缩小热交换器的轴向尺寸;壳-管程的进口温差越大,螺旋管热交换器的换热效果就越好,但为了避免螺旋管入口附近过度的热应力集中现象,有必要适当调整壳程入口的方位,以免壳程入口冷空气直接冲刷管程入口。
Single spiral tube heat exchanger has been developed for improving heat exchange effi- ciency of shell-and-tube heat exchanger and reducing complexity of structure of heat exchanger. Flow field and temperature field of the heat exchanger have been calculated by using finite element software, and it has been investigated of the influence on heat exchange efficiency of inlet flow of tube side, temperature and the cycle number of spiral pipe. The results showed that the heat exchange efficiency of spiral-tube heat exchanger has been much better than that of straight- tube heat exchanger, but the cycle number of spiral pipe has no significant impact for heat exchange efficiency, and has remarkably increased the pressure drop along the way of the tube side. The heat exchange between shell and tube has mostly happened near the entrance, thus it could make axial dimension of the heat exchanger reduced further. The greater the temperature difference of the entrance between shell side and tube side has been, the better the heat exchange efficiency of spiral-tube heat exchanger has been. However, for avoiding excessive thermal stress concentration near entrance of spiral tube, it has been necessary of adjusting entrance orientation of shell side properly for fear that cold air at entrance of shell side has directly scoured the entrance of tube side.
出处
《石油化工设备》
CAS
2013年第2期14-18,共5页
Petro-Chemical Equipment
关键词
螺旋管热交换器
换热效率
速度场
温度场
spiral tube heat exchanger
heat exchange efficiency
velocity field
temperature field
