Assessment of the pressure drop that occurs in cable-in-conduit conductors (CICCs) requires a reliable predictive model. In this paper, a fractal model to predict the pressure drop of helium flows in CICCs is proposed based on the porous media analogy and fractal theory. A fractal friction factor correlation is also derived using the proposed pressure drop model. The good agreement between the predictions and the experimental data for conductors with n1 = 3 verifies the validity of both the fractal pressure drop model and the friction factor correlation for such configuration conductors. The fractal correlation indicates that the friction factor of the cable bundle in a CICC is related not only to the void fraction but also to the average hydraulic diameter, the tortuosity of the fluid flow paths, the maximum pore size and the fractal dimension of the cable cross-section. This theoretical correlation does not contain any fitting constants and each parameter has a clear physical meaning.

中文翻译：

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基于多孔介质模拟的导管内电缆分形压降模型

对发生在导管内电缆 (CICC) 中的压降进行评估需要一个可靠的预测模型。本文基于多孔介质类比和分形理论，提出了一种预测CICC中氦流压降的分形模型。使用所提出的压降模型还导出了分形摩擦系数相关性。导体的预测和实验数据之间的良好一致性n1 = 3验证了分形压降模型和此类配置导体的摩擦系数相关性的有效性。分形相关性表明，CICC中索束的摩擦系数不仅与空隙率有关，还与平均水力直径、流体流路曲折度、最大孔径和索的分形维数有关。横截面。这种理论相关性不包含任何拟合常数，每个参数都有明确的物理意义。