Experimental and Numerical Investigations on Transition in a Laminar Separation Bubble
نویسنده
چکیده
A laminar boundary layer separates in a region of adverse pressure gradient on a flat plate, undergoes transition, and finally the turbulent boundary layer reattaches. Laminar-turbulent transition within this laminar separation bubble (LSB) is investigated by means of measurements with a Laser-Doppler-Anemometer (LDA), flow visualization in water and direct numerical simulation (DNS). The role of unsteady disturbances with and without controlled spanwise variation in the occuring mechanism of transition are examined in detail.
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