【摘要】 本文在文[1]的基础上,对矩形与三角形柔板作变幅度行波状摆动的游动方式进行了分析。进一步证实波状运动具有一个重要的流体动力学现象,即能够减弱三维效应,减少展弦比与柔板形状的影响,并且能够充分提高游动推进效率。从而说明了大量水生动物之所以采用波状游动的主要原因。文中讨论了鱼类游动的鳗鲡推进模式向鯵科推进模式的过渡,证实了尾柄收缩、尾鳍扩展是鯵科模式游鱼的重要形态适应,同时,相应的游动方式为行波波幅朝向尾端增加,不呈现完整波形。更多还原

【Abstract】 The three-dimensional waving plate theory is developed to analyze the swimming properties of rectangular and triangular waving plates with variable wave amplitude. It is confirmed that the undulatory motion can reduce three dimensional effects. This important hydrodynamic phenomenon is the main reason that the undulation is widely used as the swimming means by a large number of aquatic animals. The transition of the anguilliform mode of propulsion to the carangiform mode is discussed. It is also confirmed that the pronounced necking of body shape anterior to the tail, which benefits the propulsive performance, is a major morphological adaptation of fishes using the carangiform mode. In addition, the corresponding form of body movement is that the amplitude of undulation increases posteriorly and no complete wavelength is apparent at any time.更多还原