Influence of twisty flow heat exchanger's structural parameters on flow field and temperature field

doi:10.11949/j.issn.0438-1157.20171612

Abstract

Abstract:

Periodic whole cross-section computation models of twisty flow heat exchanger and segmental baffle heat exchanger are established respectively. The heat transfer coefficient, flow resistance and thermal performance are studied with CFD simulation. The influence of inclination angle of trapezoidal baffles, baffles width, baffles pitch and number of baffles on the heat transfer performance in the twisty flow heat exchanger was studied. The results showed that the inclination angle of trapezoidal baffles and baffles pitch have a significant effect on heat transfer performance, the effect of baffles width is secondary, and the number of baffles have no significant effect. When the thermal performance factor TEF of twisty flow heat exchanger reaches the best, compared to segmental baffle heat exchanger, the pressure drop decrease by 42.5% to 46.9%, the TEF is improved by 7.2% to 14.1%. The results of this paper provide a new scheme of the shell and tube heat exchanger for structure optimization and heat transfer enhancement.

Key words: twisty flow heat exchanger, CFD, heat transfer, numerical simulation, trapezoidal baffles

摘要：

建立扭转流换热器和弓形折流板换热器两种周期性全截面模型，采用计算流体力学方法对两种换热器的传热系数、阻力、综合性能进行了数值研究。分析了扭转流换热器管束支撑物类梯形导流板结构参数对换热器传热和流阻性能的影响。结果表明：导流板倾角和相邻两组导流板间距对扭转流换热器传热性能的影响显著，导流板宽度的影响次之，每组导流板的数量的影响较小。扭转流换热器优化结构，压降较弓形折流板换热器降低42.5%~46.9%，综合性能提高7.2%~14.1%。研究结果为管壳式换热器结构优化和强化传热提供了新方案。

关键词: 扭转流换热器, 计算流体力学, 传热, 数值模拟, 类梯形导流板

CLC Number:

TK124

GU Xin, LUO Yuankun, XIONG Xiaochao, WANG Ke, TAO Zhilin. Influence of twisty flow heat exchanger's structural parameters on flow field and temperature field[J]. CIESC Journal, 2018, 69(8): 3390-3397.

古新, 罗元坤, 熊晓朝, 王珂, 陶智麟. 扭转流换热器结构参数对流场和温度场的影响[J]. 化工学报, 2018, 69(8): 3390-3397.

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