Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 07, 2019 - November 08, 2019
In this research, the relationship between the laminar boundary layer thickness on the end wall and the Karman vortex frequency characteristics is investigated using the autocorrelation coefficient. The diameters of circular cylinder is 9 mm and the aspect ratio is kept at 25. The relative boundary layer thickness is altered between 0.37 and 0.82. The Reynolds number is kept at 3000. The measurement position is 4 times the diameter downstream from the cylinder center.
As the result, the autocorrelation coefficient of the cylinder wake depends on the boundary layer thickness. In the case of thick boundary layer thickness 0.82, the vortex shedding has fluctuations and autocorrelation coefficient decays faster than the thin boundary layer thickness 0.37.