@article{oai:nagaokaut.repo.nii.ac.jp:00000464, author = {早川, 典生 and 中村, 由行 and 椎名, 弘 and 福嶋, 祐介}, journal = {長岡技術科学大学研究報告}, month = {Oct}, note = {Clearly discernible fronts are often observed at the margin of river water discharged into the sea. The existence of coastal currents is thought to be essential to the formation of such fronts. However, their detailed formation mechanism has not been studied extensively so far. In the first part of this paper, we demonstrate the importance of the existence of the coastal current on the formation of fronts by reproducing the river water front in an experimental tank simulating coastal geographic condition. In the second part, steady-state surface gravity currents are produced in a laboratory flume as an idealized two-dimensional model for river water front. Experimentally obtained data include interfacial profile of the surface gravity currents and velocity and density profiles in the vertical. The entrainment coefficients calculated from these data exhibit the same dependence on the Richardson number as the data obtained with other two-layered flow phenomena. Interfacial profiles are compared with the calculated profiles obtained from two-layered flow equations which take both interfacial shear and entrainment across the interface into consideration. A good agreement is obtained between calculated and measured interfacial profiles by a suitable choice of the parameters in the flow equations and the result gives the non-dimensionalized length of the river water front as a function of the densimetric Froude number.}, pages = {217--223}, title = {河口フロントの形成に関する研究}, volume = {8}, year = {1986} }