砂連に関する実験的研究(3)

Abstract

Sand waves formed in a channel with movable bed are highly irregular in their shapesand sizes, therefore statistical treatment are necessary for describing them quantitatively.In this paper, the authors discussed the statistical characteristics of sand waves fromthe points of view that it might be useful to provide the interpretations for wave gene-ration and to describe the bed roughness.Characteristics of spectrum vary according to the regime of bed forms. There willbe a possibility to represent each regime of sand waves quantitatively by using the ch-aracteristics of the spectrum.Comparison of the spectral density function for bed elevation as a function of timewith the one as a function of distance shows that the propagation velocity of the sandwaves can be obtained as follows, w==CL"2 where o is the propagation velocity and Lis the wave length.Many characteristics of dunes are analogous for the one of ocean waves.