Convection Velocity Variation as a Result of Amplitude Modulation Phenomena
The paper discusses the method of convection velocity estimation in turbulent boundary layer using its relationship with amplitude modulation mechanism. To verify this method the two-point correlation measurements using hot-wire technique was applied in strong adverse pressure gradient flow for two Reynolds numbers. Additionally, streamwise velocity profiles were measured in the same locations. It was shown that the changes in the convection velocity due to Reynolds number and pressure gradient results from amplitude modulation mechanism. The convection velocity in the strong adverse pressure gradient region can be two times higher than the mean velocity in the buffer layer.
The investigation was supported by National Science Centre under Grant no. DEC-2012/07/B /ST8/03791 and statutory funds: BS/MN 1-103-305/2015/P and BS/MN 1-103-305/2016/P.
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