内容記述(抄録等) | In this paper the author considers the flow property of the head region of a turbidity current, a kind of a density current. In the experiments it was observed that the ambient fluid is entrained into a moving denser fluid at the joint between the head and the following flow. The growth rate of the maximum thickness of the head is almost constant in one run, and it increases as the slope of the bed becomes steeper. The phenomenon is treated as unsteady two-dimensional flow, and the two layers model is adopted. Governing equations of the thickness of a density current, extra density (or turbidity) and the velocity of the head are developed by use of the characteristic curve method, and the characteristic equations are integrated in the case when the growth rate of maximum thickness of the head, entrainment coefficient etc. are constant. The solutions show good agreement with experimental data.
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