Dynamical behavior of a boundary layer separation is studied using both theoretical analysis and experimental approach. The dynamical nature of the phenomenon is demonstrated on a simple case of a boundary layer in adverse pressure gradient studied experimentally. The Time-Resolved PIV technique was used to study instantaneous structure of the separation region and its time development. Distinctive coherent structures and their dynamical behavior were identified using the BOD method. and Obsahuje seznam literatury
It is proved that the first eigenfunction of the mixed boundary-value problem for the Laplacian in a thin domain Ωh is localized either at the whole lateral surface Γh of the domain, or at a point of Γh, while the eigenfunction decays exponentially inside Ωh. Other effects, attributed to the high-frequency range of the spectrum, are discussed for eigenfunctions of the mixed boundary-value and Neumann problems, too.