抄録
The turbulent flow in a square channel with weak curvature in which Re number was beyond 106 was investigated. The height of channel and the width are 5.5m and 4.8m, respectively. Numerical simulation by κ-ε model was also carried out. The calculated results except the turbulent kinetic energy were in a good agreement with the measured data in spite of a large Re number. Some interesting characteristics of turbulence in the duct were found by means of spectral analysis.The double structure of turbulence and the large coherent structure close to the inner-radius wall were recognized.