Inserts are placed inside heat exchangers to promote turbulence and maximize the heat transferred. Twisted tapes enhance heat transfer with minimal pressure drop increase for double pipe heat exchangers. Their design typically relied on experimental correlations, but nowadays CFD software is gaining interest. The choice of the turbulent model is of paramount importance and not addressed in the literature. This research aims to compare the combinations of k-ε, k-ω and RSM as well as their different wall treatments available in Ansys Fluent® and literature experimental data. Different twist ratios and Reynolds numbers are tested. Currently, no research is found in literature comparing different CFD methods for this type of units. The main objective of this research is to find the combination of RANS turbulent model and wall treatment that will most accurately reproduce the global values needed (Nusselt number and friction factor) when designing a heat exchanger with twisted tape inserts. Results show that the selection of the wall treatment is far more relevant than the turbulence model. Simulations have less discrepancy between themselves than the empirical correlations. Best performing models were k-ε Standard with ML wall treatment, which provided an average deviation from correlations ranging between 15 and 18%. K-ω SST models also provided accurate performance when estimating friction factor values with 17 to 20% deviation. Results provide clues for choosing a suitable turbulent model and are useful to minimize the error provided by the models.

插入件放置在热交换器内，以促进湍流并最大限度地传递热量。双管换热器的双绞带以最小的压降增加来增强传热。他们的设计通常依赖于实验相关性，但如今 CFD 软件正在引起人们的兴趣。湍流模型的选择至关重要，文献中并未涉及。本研究旨在比较 k-ε、k-ω 和 RSM 的组合以及 Ansys Fluent® 中可用的不同壁面处理方法和文献实验数据。测试了不同的捻比和雷诺数。目前，在比较此类单元的不同 CFD 方法的文献中没有发现研究。本研究的主要目的是找到 RANS 湍流模型和壁处理的组合，以便在设计带有扭曲带插件的热交换器时最准确地再现所需的全局值（努塞尔数和摩擦系数）。结果表明，壁处理的选择比湍流模型更相关。与经验相关性相比，模拟之间的差异更小。表现最好的模型是采用 ML 壁处理的 k-ε 标准模型，它提供的相关性平均偏差在 15% 到 18% 之间。K-ω SST 模型在估计具有 17% 到 20% 偏差的摩擦系数值时也提供了准确的性能。结果为选择合适的湍流模型提供了线索，并有助于最大限度地减少模型提供的误差。