Stochastic Approach to Sediment Transport Process by Wave Superimposed on Current.
Grant-in-Aid for General Scientific Research (B)
|Allocation Type||Single-year Grants |
|Research Institution||KYOTO UNIVERSITY |
NAKAGAWA Hiroji Kyoto Univ., Civil Engrg., Professor, 工学部, 教授 (60027216)
NAKANO Susumu Tokushima Univ., Civil Engrg., Lecturer., 工学部, 講師 (50198157)
MURAKAMI Shogo Kyoto Univ., Civil Engrg., Instructor., 工学部, 助手 (70166247)
KNISELY C. W. Kyoto Univ., Civil Engrg., Lecturer., 工学部, 講師 (40197629)
NEZU Iehisa Kyoto Univ., Civil Engrg., Associate Professor., 工学部, 助教授 (30109029)
清水 義彦 京都大学, 工学部, 助手 (70178995)
|Project Period (FY)
1988 – 1989
Completed (Fiscal Year 1989)
|Budget Amount *help
¥6,400,000 (Direct Cost: ¥6,400,000)
Fiscal Year 1989: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1988: ¥4,300,000 (Direct Cost: ¥4,300,000)
|Keywords||Non-Equilibrium Sediment Transport Process / Stochastic Model / Pick-up Rate / Step Length / Unsteady Flow / 波・流れ共存場 / ステップレンプス / 非一様境界形状 / 流砂 / 乱流モデル|
Even if the boundary geometry is non-uniform and the flow is unsteady, non- equilibrium sediment transport processes are reasonably and systematically described by the generalized stochastic model , which are consisted of the pick-up rate, step length , moving period and moving speed of a sand particle. The pick-up rate, step length, moving period and moving speed of a sand particle can be dynamically evaluated in terms of the equation of motion of a sand particle with particular reference to the probabilistic factors of the flow structures and boundary configuration. The generalized expression for the non-equilibrium sediment transport law and the respective characteristics of sand movement are formulated for the various types of flows under the various boundary conditions.
The useful and simple expressions for the below conditions have been obtained.
(1) the steady and non-uniform flow over the sinusoidaly varying plane and bed configuration;
(2) the steady and non-uniform flow over the triangular sand dunes;
(3) the unsteady flow which are characterized the various types of discharge hydrograph;
(4) the current accompanied with the oscillatory flow;
(5) the current accompanied with the wave.
The minute experiments for the cases of (1)-(4) were carried out concerning the flow structures and the bed load transport process, and a great deal of data were collected. The obtained informations for the flow structures are applied to the above-mentioned models for the sand movement. The obtained results show the good agreement with the experiments. For the type of flow of (5), the characteristics of sand movement are evaluated based on the collected experimental results by other researchers. The theoretical formulation agrees well with the experimental data.
It is recognized that the generalized stochastic model for sediment transport process are very effective to the non-equilibrium bed load motion in the spatially non-uniform and unsteady flow.
Report (3 results)
Research Products (7 results)