斜め段落ち流れに関する実験的研究

Abstract

In order to elucidate the physical significance of thc criterion of alternating bar formation inprevious paper1), experimental work has been carried out on the hydraulic characteristics of theflow over abrupt drops with oblique edge to mean flow direction, which are adopted as simplifiedmodels of alternating bars at early stage of their developing process.In this paper, experimental results of the distribution of flow velocity and direction and thebrief examination in the shift of main flow part, the characteristic of separation zone under obliqueedge and the vorticity variation of average flow are described. Finally, the correspondence of theflow over these abrupt drops to that over alternating bars is discussed and the following results areconcluded: The macroscopic view of the former flow is resemble to the latter under the conditionof rather long edge and small depth, and it has large posibility that bars with twice to four timeslength of channel width are predominant at early stage of their growing process.