Abstract In the present work, numerical investigation is applied to study the thermal and hydraulic characteristics of a new type of helically coiled tube heat exchangers called “sector-by-sector heat exchangers”. The studied flow regime is turbulent. It was simulated using the realizable K-e model. In addition to these types of the heat exchangers, the tube-in-tube helical coil are also investigated and compared. The model is validated by comparing the Nusselt number and friction factor with the predicted values which are obtained using the previous experimental correlations. The Reynolds number, sector angle and its orientation, dimensionless pitch and coil diameter effects on the Nusselt number and friction factor are analyzed. For each types of these heat exchangers, equations are suggested for the estimation of the Nusselt number and friction factor as functions of those mentioned parameters. Furthermore, the coefficient of the thermal and hydraulic performance of these heat exchangers are compared with an example. It was found, the semi-circular cross section sector-by-sector heat exchangers are more efficient than quadrant-circular cross section and tube-in-tube heat exchangers.

中文翻译：

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作为一种新型换热器的逐段螺旋盘管换热器的热力和水力性能分析

摘要 在目前的工作中，应用数值研究来研究一种称为“逐扇区换热器”的新型螺旋盘管换热器的热力和水力特性。研究的流态是湍流。使用可实现的 Ke 模型对其进行了模拟。除了这些类型的热交换器外，还对管中管螺旋盘管进行了研究和比较。该模型通过将 Nusselt 数和摩擦系数与使用先前实验相关性获得的预测值进行比较来验证。分析了雷诺数、扇形角及其方向、无量纲节距和线圈直径对努塞尔数和摩擦系数的影响。对于这些热交换器的每种类型，建议使用方程来估计作为上述参数的函数的 Nusselt 数和摩擦系数。此外，这些换热器的热力和水力性能系数与一个例子进行了比较。结果表明，半圆形横截面逐扇区换热器比象限圆形横截面和管中管换热器更有效。