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Abstract: |
As a universal principle of turbulence cascade,scaling law is important in the research on statistics of turbulence.In the thesis PIV system is used to measure the streamwise velocity vector(u’) and the component of vorti-city (dv’/dx) in order to analyze the parameters of SL scaling law in the boundary layer at Reθ=2694 (Reθ is obtained by the momentum thickness and free flow velocity).The method of wavelet and statistics are used in this paper.Then,the parameters of SL scaling law are fitted with the scaling law of extended self similarity,extended of refined similarity hypothesis and a new form of refined similarity.At different distances from the wall and different scale,the results show that the fitted curves of u’ is in accordance with experimental curves.For dv’/dx,the fitted curves which are fitted with extended of refined similarity hypothesis and a new form of refined similarity is in accordance with experimental curves. |
Key words: the exponent of the most intermittent structure the intermittence factor PIV turbulent boundary layer |
DOI:10.11916/j.issn.1005-9113.2011.04.021 |
Clc Number:O357.5 |
Fund: |