抄録
Direct numerical simulation and large eddy simulation were performed for a curved channel. In the developed turbulent flow, the spanwise length of the computational domain was changed and behavior of the large-scale vortex was examined. As for the large-scale vortex, it was suggested that negative value of normal velocity can be used as detector of the large scale structure. In the process of the development, thin streamwise structures occur in the computational domain, and, however, these structures grow into large scale vortex.