According to Kelvin, a point pressure source uniformly traveling over the surface of deep calm water leaves behind universal wake pattern confined within $39°$ sector and consisting of the so-called transverse and diverging wavefronts. Actual ship wakes differ in their appearance from both each other and Kelvin’s prediction. The difference can be attributed to a deviation from the point source limit and for given shape of the disturbance quantified by the Froude number $F$. We show that within linear theory effect of arbitrary disturbance on the wake pattern can be mimicked by an effective pressure distribution. Further, resulting wake patterns are qualitatively different depending on whether water-piercing is present or not (“sharp” vs “smooth” disturbances). For smooth pressure sources, we generalize Kelvin’s stationary phase argument to encompass finite size effects and classify resulting wake patterns. Specifically, we show that there exist two characteristic Froude numbers, $F_1$ and $F_2>F_1$, such as the wake is only present if $F\gtrsim F_1$. For $F_1\lesssim F\lesssim F_2$, the wake consists of the transverse wavefronts confined within a sector of an angle that may be smaller than Kelvin’s. An additional $39°$ wake made of both the transverse and diverging wavefronts is found for $F\gtrsim F_2$. If the pressure source has sharp boundary, the wake is always present and features additional interference effects. Specifically, for a constant pressure line segment source mimicking slender ship the wake pattern can be understood as due to two opposing effect wakes resembling (but not identical to) Kelvin’s and originating at segment’s ends.

根据开尔文（Kelvin）的观点，均匀分布在深层平静水面上的点压力源留在了被限制在 $39°$由所谓的横向和发散波前组成。实际的船舶尾流在外观上和开尔文的预测都不同。差异可归因于与点源极限的偏差，以及对于给定形状的扰动，其通过弗洛德数进行了量化$F$。我们表明，在线性理论内，任意扰动对尾流模式的影响可以通过有效的压力分布来模拟。此外，取决于是否存在穿水功能，最终的唤醒模式在质量上会有所不同（“尖锐”干扰与“平滑”干扰）。对于平滑压力源，我们将开尔文的固定相论点进行概括，以包含有限大小的影响，并对产生的尾流模式进行分类。具体来说，我们表明存在两个特征弗洛德数，$F_{\mathrm{1个}}$ 和 $F_2>F_{\mathrm{1个}}$，例如只有在 $F\gtrsim F_{\mathrm{1个}}$。对于$F_{\mathrm{1个}}\lesssim F\lesssim F_2$，尾流由横向波前组成，这些横向波前被限制在一个可能小于开尔文的角度的扇区内。额外的$39°$ 发现由横向和发散波前构成的尾波 $F\gtrsim F_2$。如果压力源具有尖锐的边界，则始终存在尾流，并具有其他干扰作用。具体地，对于模拟细长船的恒压线段源，尾流模式可以理解为归因于两个相反的效应，它们类似于开尔文（但不等同于）并起源于段的末端。