The problem of predicting a ship’s form factor and associated scale effects has been subject to many investigations in recent years. In this study, an attempt is made to investigate whether the form factor is influenced by a change in the ship’s speed by numerically modelling a geosim series of the KCS hull form by means of a RANS solver. The turbulence dependence of the problem is also studied by altering the closure model among three widely used approaches (the k-ω, k-ω SST, and k-ε models). The results show that at very low speeds (Froude numbers in the range of 0.02–0.06) the numerical model predicts changes in the form factor of a ship between 10% and 20%, depending on the turbulence model and scale factor choices. As the speed is increased further, the form factor exhibits little change, usually in the range of 1% or less. Simulations where the Reynolds number is changed by approximately two orders of magnitude, achieved by altering the value of viscosity, confirmed that the form factor can be considered Froude-dependent only for low speeds, predicting essentially identical values when high speed cases are considered.

近年来，预测船舶外形尺寸和相关比例效应的问题已受到许多研究的关注。在这项研究中，通过使用RANS求解器对KCS船体形式的geosim系列进行数值建模，试图研究形状因素是否受到船速变化的影响。还通过在三种广泛使用的方法（k-ω，k-ωSST和k-ε）之间更改闭合模型来研究问题的湍流依赖性楷模）。结果表明，在极低的速度下（弗劳德数在0.02–0.06范围内），数值模型可以预测船的形状系数在10％到20％之间的变化，具体取决于湍流模型和比例因子的选择。随着速度的进一步提高，形状系数几乎没有变化，通常在1％或更少的范围内。通过改变粘度值将雷诺数改变大约两个数量级的模拟结果证实，仅当低速时，才可以将形状因数视为Froude依赖性，而在考虑高速情况时，则可以预测出基本上相同的值。