Study Of Michell's Integral And Influence Of Viscosity And Ship Hull Form On Wave Resistance
Study Of Michell's Integral And Influence Of Viscosity And Ship Hull Form On Wave Resistance
复制标题
米歇尔积分及粘度和船体形状对波浪阻力影响的研究
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
Gotman A. Sh
中科院分区：
文献类型：
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作者：
A. Sh;D. Tech;Gotman A. Sh
对Michell积分进行了系统的研究，并对线性理论与实验之间的差异进行了调查。特别注意粘性的影响，船头和船尾系统的船波的相互作用。通过双支柱试验，揭示了流体粘性对船舶兴波阻力影响的机理。这个实验反驳了一种流行的观点，即由于边界层、尾流和船体的遮蔽作用，实验曲线中没有隆起和凹陷。我们的计算证实了这一假设，即船首波的能量的某一部分被浪费在湍流的流动周围的移动船舶，不参与与船尾系统的波的相互作用。新形式的米歇尔积分，其中单调部分是分离的振荡部分，使人们有可能确定以前未知的特点，这一积分。第一次分析和实验方法建议的原因，波阻在低速和高速应分别研究。从修正的Michell积分形式出发，得到了选择波阻最小的船体形状的新的比较准则，并对不同方程描述的模型进行了验证。该方法提供了与已知形式良好协调的最佳形式。研究了船体表面曲率对波浪阻力的影响，得到了一个综合所有可能的船体形状的曲线图。结果表明，具有圆柱形前体的“简化”船体形状具有最大可能的波浪阻力值，这也是为什么前球头的设计是一个极其棘手的问题。
A systematical study of Michell’s integral was carried out and an investigation into a discrepancy between the linear theory and experiment was conducted. Special attention was given to the influence of viscosity on the interaction of the bow and stern systems of ship waves. An experiment with two struts provided information about the mechanism of influence of viscosity of a fluid on the ship wave resistance. This experiment argued against a popular opinion that the humps and hollows are absent in an experimental curve because of the action of the boundary layer, the wake, and the hull sheltering effect. Our calculations confirm the hypothesis that a certain part of the bow wave’s energy is wasted on turbulence of a flow around the moving ship and does not participate in the interaction with the stern system of waves. The new form of Michell’s integral in which the monotone part is separated from the oscillatory part made it possible to determine the previously unknown peculiarities of this integral. For the first time analytical and experimental methods suggested the reason why the wave resistance at low and high speeds should be investigated separately. The new comparative criterion of choosing a ship hull form with the least wave resistance was obtained from the modified form of Michell’s integral and then verified for models described by different equations. This method provided optimum forms that were well coordinated with the known forms. The study of the influence of the ship hull surface curvature on wave resistance produced a graph combining all possible ship hull forms. It was shown that the “simplified” hull shapes with cylindrical fore bodies have the largest possible value of wave resistance and why the design of fore bulbs is an extremely tricky matter.