| The cylinder wakes/turbulent boundary layer interacting flows are frequent phenomena in aviation engineering and impeller machines. An experiment had been devoted to investigate the characteristics of multi-scale coherent eddy structures in the cylinder wakes/turbulent boundary layer interacting flows. The streamwise velocities after a cylinder, which was located in developed wall turbulence in the wind tunnel, were accurately measured by the IFA-300 constant temperature anemometer and a single hot-wire. And the velocity profiles normalized by inner scale were compared to the one of standard situation. Wavelet transform was used to analyze the velocities measured near the wall. And different situations were conducted by changing the diameter of the cylinder and the distance to the plate.The results indicate that, the enhanced effect to the energy and conditional average shape of the multi-scale coherent eddy structures near the wall is particularly marked when the cylinder is close to the wall. The closer cylinder gives more effect to the point higher like y+=300. And there is no influence to the structures when the cylinder is located at the edge of the boundary layer. As far as a cylinder is concerned, the upper wakes uplift the influence much more than the lower ones. While the upper cylinder gives more effect than the lower one that is located symmetry of the measure point. The intensity of the influence weakens along the streamwise, whereas it could be found at the area as far as about 40 times of the cylinder diameter downstream. The exact range of the cylinder wakes effect is still available for the further studies.The conditional average phases of the multi-scale coherent eddy structures in the logarithmic area are changed by the cylinder wakes, which means that the variety of the velocity is changed. The positive peak values are often larger than usual situation and the compress process in the middle is enhanced. The shapes of the average phases are no longer symmetry.
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