CIESC Journal ›› 2016, Vol. 67 ›› Issue (S1): 232-238.DOI: 10.11949/j.issn.0438-1157.20160215

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Numerical simulation of multi-flow and heat transfer characteristics in heat exchangers with triple-helical baffles

DUAN Zhenya, SHEN Feng, ZHANG Junmei, SONG Xiaomin, CAO Xing   

  1. College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266000, Shandong, China
  • Received:2016-02-29 Revised:2016-03-15 Online:2016-08-31 Published:2016-08-31
  • Supported by:

    supported by the Shandong Province Taishan Scholar Engineering under Special Funding and the Science and Technology Planning Project of Shandong Provincial Education Department (J12LD15).

三螺旋折流板换热器多流路通道流动与传热数值模拟

段振亚, 沈锋, 张俊梅, 宋晓敏, 曹兴   

  1. 青岛科技大学机电工程学院, 山东 青岛 266000
  • 通讯作者: 曹兴,jamesshenfeng@163.com
  • 基金资助:

    山东省泰山学者工程专项;山东省高等学校科技计划项目(J12LD15)。

Abstract:

Triple helical baffle heat exchanger was proposed to arrange more helical baffle in shell side with large helix angle and enhance heat transfer rate. In this paper, the flow characteristics and heat transfer performance of heat exchangers with triple helical baffles were analyzed. The comprehensive performance between single-helical and triple-helical baffle heat exchangers were compared based on the calculating results of pressure drop and heat transfer coefficient when Reynolds number ranges from 1391-4174. The results showed that:heat transfer coefficient and JF factor of triple-helical baffle heat exchangers is 27.9% higher and 13.67% higher than single-helical baffle heat exchanger respectively. Besides entransy dissipation theory was used to analyze the heat transfer performance of triple-helical baffle heat exchanger with different helix angle, and triple-helical baffle with 64.8° got the lowest entransy dissipation rate. The heat transfer rate of central tube and outer tube were compared, outer tube have higher heat transfer rate compared with central tube.

Key words: continuous helical baffles, heat exchanger, triple-helical, entransy dissipation, numerical simulation

摘要:

为了增加大螺旋角下单位长度换热管上螺旋折流板数量提高换热,提出三螺旋折流板导流结构,对设置三螺旋折流板后壳程流体的流动与传热进行了数值模拟,重点考察了Reynolds数Re=1391~4174时的壳程压降及对流传热系数,与设置单螺旋折流板的对比结果表明:三螺旋折流板换热器壳程对流传热系数高27.9%,JF因子高13.67%,综合传热性能更好。在此基础上运用耗散理论分析了三螺旋折流板采取不同螺旋角时对换热效率的影响,发现由传热引起的耗散率随Reynolds数变化规律与壳程对流传热系数随Reynolds数的变化规律类似,相同流量条件下螺旋角为64.8°的换热器耗散率最小。另外,中心换热管与壳壁附近换热管的传热系数比较结果显示,中心管热交换量均低于壳壁附近换热管热交换量。

关键词: 连续螺旋折流板, 换热器, 三螺旋, 耗散, 数值模拟

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