求翻译：压降小：没有折流板，管壳中介质直接螺旋流动，大大增大了每个压力降的单位热传递效率。和有普通管壳式换热器相比，一般热传递效率在同一压力降的情况下提高40%。反过来说，在同一热传递效率下，压力降可能降低一半。还有，螺旋扁管换热器管程中介质做螺旋流动，这种螺旋流动提高的效率比通常插入螺旋带的效果更好，见图2所示。其结果是与传统的换热器相比，在相同压降的情况下，螺旋扁管换热器大大降低了传热面积，传热效率得到很大的提高。是什么意思？

Pressure drop: Baffled, the media directly in the shell and tube spiral flow, which greatly increases heat transfer efficiency of each unit pressure drop. And compared to ordinary shell and tube heat exchanger, heat transfer efficiency increased by 40% under the same pressure drop. Conversely, in th

Minimal pressure drop: no baffle plate, tube and Shell Helix media flow directly and significantly increase the pressure drop per unit of heat transfer efficiency. And there is a shell-and-tube heat exchanger, a heat transfer efficiency in general with a pressure drop of 40 per cent increase. Conver

Small pressure drop: no baffles, media d