Experimental Study of Energy Dissipation Rate Scaling Law in Turbulent Boundary Layer
湍流能量耗散率标度律实验研究

Particle-image Velocimetry (PIV) system was used to measure the instantaneous streamwise velocity and longitudinal velocity in turbulent boundary layer on a flat plate. The turbulent energy dissipation rate was obtained by axisymmetric homogeneous hypothesis.In order to study turbulent energy dissipation rate scaling law, traditional statistics method was used to analyze experimental data. For different scales and different wall distances, experimental investigation indicates that turbulent energy dissipation rate scaling law is universal at small scale, in other words, turbulent energy is dissipated in small scale in turbulent boundary layer. In addition, the most intensive structure is proposed in further study based on Hierarchical-Structure model hypothesis. It is concluded that there exists an absolute scaling exponent for this most intensive structure in turbulent boundary layer, and the statistical absolute scaling behavior only produced the local and strong intermittence structure.