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Hebbar, Sheshagiri K.

Publications and source records attributed to Hebbar, Sheshagiri K..

Three-Dimensional Turbulent Boundary Layer With Adverse Pressure Gradient

Report describes experiment to measure effects of adverse pressure gradient on three-dimensional turbulent boundary-layer flow; effect of streamwise gradient of pressure on crossflow of particular interest. Production of turbulent kinetic energy grows rapidly in vicinity of step as result of steep mean-flow velocity gradients. Dissipation grows less quickly than production; leading to net growth with distance along streamline.

Driver, David M.↗

Three-dimensional shear-driven boundary layer flow with streamwise adverse pressure gradient

The effects of adverse pressure gradient on a three-dimensional turbulent boundary layer are studied in an axisymmetric forward-facing step geometry. Velocity measurements made using a three-component laser Doppler velocimeter include mean flow as well as Reynolds stresses and velocity triple-product correlations. Turbulent Prandtl mixing-lengths are extracted from the data, showing the effects of curvature. Streamwise pressure gradient was seen to alter streamwise velocity and Reynolds stress without significantly affecting transverse velocity and Reynolds stress. Transverse-strain was seen to have the effect of reducing the streamwise component of Reynolds stress.

Driver, David M.↗