Abstract
The immersed tunnel crossing the Bosphorus Strait located in Istanbul, Turkey, is under construction. It is known that the current field of the Bosphorus Strait is complicated. It has two-layer flow of surface southward and bottom northward. In this paper, the numerical hydrodynamic simulation, which is carried out to clarify the current structure, is described. This simulation results are used for construction assistance system.
For the simulation, the salinity and temperature boundary conditions of both northern and southern ends of the strait are vertically given as step function. The simulation results agree with monitoring results well. Through the simulation, following results are found out. Large water level difference between both ends of the strait causes the increase of the current speed of both surface and bottom layers. However, in one range of the water level difference, the maximum current speed of the surface layer reaches a constant value of 1.8 m/s approximately. The current structure is mainly ruled by the shape of the density interface.
