Measurement of Wall Shear Stress in Transitional Boundary Layer on a Flat Plate Using Computational Preston Tube Method

CPM을 이용한 평판위 천이경계층에서 벽 마찰응력의 계측

A CPM (computational preston tube method) was developed to measure wall shear stress in a transitional boundary layer on a flat plate using Preston tubes. Correlation for the displacement factor of Preston tubes was improved for a CPM to be used in the transitional boundary layer. The distribution of skin-friction coefficient was reasonably predicted in the uniform free stream of 3.1% turbulence intensity. Reasonable and accurate estimation of displacement factor of Preston tubes was found to be of crucial importance for the CPM, especially in the laminar boundary layer. The mean velocity profiles of the boundary layer on the plate were also measured and presented.