Abstract A circle-arc-wavy helically coiled pipe heat exchanger (CAWC) was proposed and numerically studied. The CAWC is formed by dividing a conventional helically coiled heat exchanger into several (Nbend) segments uniformly and rotate each segment upward and downward alternatively around the chord of the arc with an angle φ. Water under atmosphere pressure was employed as the working fluid. The results showed that the local convective heat transfer coefficient was extremely sensitive to the inlet boundary conditions and showed stochastic characteristics. The mechanism of convective heat transfer enhancement induced by chaotic advection was analyzed using an improved field synergy analytical method. The results showed that the local and total convective heat transfer coefficients always coincided with the variation of the h′ (ρuCpcos(θ);θ: synergy angle) field, suggesting that the enhancement of the h′ field is the main reason for convective heat transfer enhancement induced by chaotic advection. Parameter analyses on the CAWC were conducted with Nbend = 4, 6, and 8; φ = 30°, 60°, 120°, and 180°; Re = 200, 400, 800, 1600 and 3200. It was found that under the same pumping power and heat exchanging area, the total convective heat coefficient of the CAWC can be increased by 40%, relative to the conventional coiled heat exchanger.

中文翻译：

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基于混沌对流的圆弧波浪螺旋盘管换热器热工水力性能数值研究

摘要 提出并数值研究了一种圆弧波纹螺旋盘管换热器(CAWC)。CAWC是将传统的螺旋盘管式换热器均匀地分成若干（Nbend）段，每段绕圆弧的弦向上和向下交替旋转一个角度φ而形成的。大气压下的水用作工作流体。结果表明，局部对流传热系数对入口边界条件极为敏感，表现出随机特性。采用改进的场协同分析方法分析了混沌对流增强对流换热的机理。结果表明，局部和总对流换热系数始终与 h' (ρuCpcos(θ);θ: 协同角）场，表明 h' 场的增强是混沌平流引起的对流换热增强的主要原因。CAWC 的参数分析是在 Nbend = 4、6 和 8 下进行的；φ = 30°、60°、120°和180°；Re = 200、400、800、1600和3200。研究发现，在相同的泵送功率和换热面积下，CAWC的总对流热系数相对于常规盘管换热器可提高40%。