The Lagrangian structure function＇s scaling exponents and intermittency of three-dimensional incompressible turbulent channel flow are investigated by using direct numerical simulation. The intermittency in streamwis...The Lagrangian structure function＇s scaling exponents and intermittency of three-dimensional incompressible turbulent channel flow are investigated by using direct numerical simulation. The intermittency in streamwise velocity increments is found to increase in the near-wall region, which can be attributed to the presence of strong mean shear and organized motions in the near-wall region. It is found that the intermittency of transverse velocity increments is weaker than that of longitudinal ones. The present ESS evaluation of ζL（q） for the structure function of the streamwise velocity component in the channel centre is fairly close to experimental estimates of isotropic turbulence.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 10742005, Shanghai Pujiang Program under Grant No 08PJ1409100, and Shanghai Institute of Technology （YJ2007-26）.
文摘The Lagrangian structure function＇s scaling exponents and intermittency of three-dimensional incompressible turbulent channel flow are investigated by using direct numerical simulation. The intermittency in streamwise velocity increments is found to increase in the near-wall region, which can be attributed to the presence of strong mean shear and organized motions in the near-wall region. It is found that the intermittency of transverse velocity increments is weaker than that of longitudinal ones. The present ESS evaluation of ζL（q） for the structure function of the streamwise velocity component in the channel centre is fairly close to experimental estimates of isotropic turbulence.
