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1、螺旋折流扳换热器常常有许多传热在石油，化工，电力，冶金，能源等工业部门所涉及的问题。 The shell and tube heat exchanger is the heat transfer equipment most widely used in the current industrial production.在管壳式换热器是换热设备在目前最广泛用于工业生产。 Compared with other types, its main advantages are the large heat transfer area in the unit volume and good heat
2、 transfer effect.与其他类型相比，它的主要优点是大型热单位体积传热效果和良好的换热面积。 Combined with a simple structure, wide range of materials required in manufacturing, and greater operation flexibility, it is more and more widely used in the chemical engineering fields.具有结构简单，制造所需的各种材料和更大的操作灵活性相结合，越来越广泛地在化工领域使用。 To increase the
3、speed of shell fluid and intensify the turbulent level to improve the shell film coefficient of heat transfer, the traverse baffle is usually installed in the shell and tube heat exchanger.为了提高速度，加大壳程流体的湍流水平，以改善壳膜传热系数，横向挡板通常安装在管壳式换热器中。 The most common one is segmental baffle.最常见的是弓形折流。 Fluid winds i
4、n the shell outfit with segmental baffle at the continuously changing speed in different directions, and is easy to separation especially in the baffle edge.流体与弓形折流壳装在不同的方向，以适应不断变化的速度，这样就很容易分离，特别是在挡板的边缘。 Due to the flow dead zone between segmental baffles and the shell, fluid undergoes repeated move
5、ment of cross streams in the baffles, resulting in the reduction of driving force of heat transfer.由于流体弓形与壳体死区之间流动，流体经过反复十字运动经过溪流挡板，使驱动力的传热减少。 For obtaining higher heat transfer performance, only the plate spacing is reduced, which is inevitably accompanied by a higher flow resistance at the cost of
6、 higher energy consumption.为了获得更高的传热性能，板间距仅减少，在流动阻力陪同下成本较高和更高的能源消耗的是不可避免的。 Therefore, the traditional form change of baffle is badly needed.因此，改变传统形式的挡板，是迫切需要的。 Fig.图。 1 The Shell Flow Diagram of Heat Exchanger with Segmental Baffles 1，壳式换热器流程图弓形器 The heat exchanger with helical baffles becomes an i
7、deal alternative because of its unique advantages.螺旋隔板换热器之所以成为一个独特的优势，因为It uses the continuous helical backing plate in support of heat exchange tube to make the shell medium do the inclined forward movement along the spiral channel from the shell entrance.它使用的热交换管支撑连续螺旋垫板，使壳中做从壳沿螺旋通道入口处的斜向前运动。 Sinc
8、e the traditional horizontal baffling way is changed to the vertical helical baffling means, the heat exchanger with helical baffles greatly enhances its heat transfer effect while reducing the resistance of shell side.由于传统的水平方式改为垂直螺旋式的螺旋折流板换热器，大大提高了换热效果，同时降低了壳侧阻力。 Its characteristics are: (1) The c
9、ontinuous smooth spiral flow of medium in the shell side avoids the serious pressure loss caused by horizontal baffling with lower pressure drop.其特点是：（1）连续介质中的螺旋壳侧流避免了严重的压力损失和更低的的压降水平造成的。 (2) Compared with the segmental baffle, in the state of same pressure drop, it can significantly improve the she
10、ll medium flow rate, and thereby increase the turbulence level and the medium heat transfer capability. （2）与弓形折流相比，在相同压降状态，它可以显着提高壳介质流量，从而提高水平和动荡中的传热能力。 (3) The spiral movement of the shell medium generates velocity gradient on the radial cross-section and form radial turbulence in favor of the thin
11、ned bottom layer of the heat-exchange surface detention and the enhanced film heat transfer coefficient. （3）壳中的螺旋运动产生的径向截面和在冷热交换表面拘留底层变薄和增强膜传热系数径向湍流速度有利于形成梯度。 (4) There is no dead zone. （4）没有死区。 While improving the heat transfer coefficient, the vertical helical baffling way reduces dirt deposition,
12、 has stable thermal resistance, and allows the heat exchanger in a highly efficient running state.同时提高了传热系数，垂直螺旋莫名其妙地减少污垢沉积，具有稳定的耐热性，并允许在一个高效换热的运行状态。 (5) Thanks to the stronger constraints on the heat exchanger than the segmental baffle, the helical baffle lessens the tube bundle vibration and exten
13、ds the operational life. （5）就比弓形折流式换热器的强大制约下，螺旋隔板减少了管束振动，延长使用寿命。 (6) When the shell is condensing for heat exchange, the helical baffle can play the role of drainage of the condensate liquid, decrease the coverage of the condensate liquid on the lower rows of tubes, and thereby enhances the effect o
14、f heat transfer. （6）当外壳进行热交换凝结，螺旋隔板可以起到排水作用，凝析液减少了冷凝水的覆盖面，具有较低的管行液体，从而增强了传热效果。 According to StehlikPs researches, compared with the traditional heat exchanger with segmental baffles, the heat exchanger of helical baffle gets 1.8 times higher of the heat transfer coefficient and 25% lower of flow res
15、istance in the same condition.据StehlikP的研究，在相同的条件下，相对于传统的弓形换热器，螺旋折流板换热器获得1.8倍的传热系数和25的流动阻力。 Chen Shixing concludes: for high-viscosity oil, the heat exchanger with helical baffles has the convection heat transfer coefficient of about 1.5 times in the unit pressure drop that that of the ordinary heat
16、 exchanger with segmental baffles; for water, about 2.4 times.陈师兴结论：高粘度油，螺旋折流板换热器的对流换热装置中的压力下降，改用用弓形换热器是普通换热器的约1.5倍系数，对水，约是2.4倍。 Song Xiaoping presents the application of over ten units of heat exchangers with helical baffles in the refinery, and finds that its performance indicators are better than the original segmental baffle heat exchanger.宋晓平介绍了以上的炼油厂在螺旋折流板换热器十个单位的申请，并认为，其性能指标均优于原来的弓形折流式换热器更好。 The heat exchanger with helical baffles makes the efficiency of heat transfer g
