2012 年 68 巻 4 号 p. I_43-I_48
This paper reports on continues an experimental investigation of characterizing transition to turbulence for solitary wave boundary layer in a smooth bed condition. A series of experiments has been carried out using a closed conduit generation system over the Reynolds number (Re) range 5.64 x 105 - 7.34 x 105. Additionally, the instantaneous velocities were measured by a Laser Doppler Veloci-meter (LDV) over 50 wave numbers and at 17 to 22 points in the vertical direction. The turbulence intermittency has been analyzed based on experimental data. Moreover, momentum method has been employed for calculating bottom shear stress for all cases. And then, the turbulence intensity is plotted to give clearly description how turbulence generated in the various values of Re. The phase difference obtained from the present experiment has an excellent agreement with the result of previous studies. Inconsistency critical (Re) (Recr) can be found in solitary wave case in terms of phase difference, this observable fact is different with sinusoidal wave case which has consistency in Recr.
