摘要
The scaling properties of high-order Lagrangian velocity structure functions are investigated numerically for a turbulent flow with a friction-velocity based Reynolds number Re_τ=80.The Lagrangian particles are released from locations of different distances to the wall.The relative scaling exponents of the longitudinal velocity component are found to increase with the released distance to the wall and to approach asymptotically to theoretical predictions.However,the scaling exponents of the transverse velocity component are smaller than ,indicating a more intermittent nature.Specifically for the release locations in the center region,the relative scaling exponents agree very well with theoretical predictions.
The scaling properties of high-order Lagrangian velocity structure functions are investigated numerically for a turbulent flow with a friction-velocity based Reynolds number Re_τ=80.The Lagrangian particles are released from locations of different distances to the wall.The relative scaling exponents of the longitudinal velocity component are found to increase with the released distance to the wall and to approach asymptotically to theoretical predictions.However,the scaling exponents of the transverse velocity component are smaller than ,indicating a more intermittent nature.Specifically for the release locations in the center region,the relative scaling exponents agree very well with theoretical predictions.
基金
Project supported by the National Natural Science Foundation of China (Grant Nos.11172179,11102114)
the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry (Grant No.zx2010-12)
the Shanghai Municipal Education Commission (Grant No.11ZZ87)
the Shanghai Pujiang Program (Grant No.08PJ1409100)
