Abstract The conventional extrapolation of ship resistance from model tests to full scale presumes that the coefficient of wave-making resistance (Cw) depends on the Froude number only. This leads to the assumption that Cw of a ship is identical to Cw of its scaled model. However, this assumption is challenged in shallow water due to viscous effects, which are represented by the Reynolds number (Re). In this study, different scales (different Re) of the Wigley hull and the KCS hull are used to investigate the scale effects on Cw numerically. After verification and validation, systematic computations are performed for both ships and their scaled models in various shallow-water conditions. Based on the results, significantly larger values of Cw are found for the KCS at model scale in very shallow water, suggesting that the conventional extrapolation has to be reconsidered. Additionally, this study reveals the relationship between the changes in frictional resistance coefficient (Cf) and the changes in Cw caused by shallow water, which benefits the prediction of shallow water effects on Cw. Finally, use of a larger ship model, where the Re is also higher, is recommended for resistance tests in shallow water to reduce scale effects on Cw.

中文翻译：

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尺度对浅水船舶造浪阻力的影响

摘要 船舶阻力从模型试验到全尺寸的常规外推假定造浪阻力系数（Cw）仅取决于弗劳德数。这导致假设船舶的 Cw 与其比例模型的 Cw 相同。然而，由于粘性效应（由雷诺数 (Re) 表示），该假设在浅水中受到挑战。在本研究中，Wigley 船体和 KCS 船体的不同尺度（不同 Re）用于数值研究尺度对 Cw 的影响。经过验证和验证，对两种船舶及其比例模型在各种浅水条件下进行系统计算。根据结果​​，在非常浅的水域中，模型尺度的 KCS 发现了明显更大的 Cw 值，表明必须重新考虑传统的外推法。此外，本研究揭示了摩擦阻力系数（Cf）的变化与浅水引起的Cw变化之间的关系，有利于预测浅水对Cw的影响。最后，建议使用更大的船模型，其中 Re 也更高，用于浅水阻力测试，以减少对 Cw 的规模效应。