Pj multideck1/19/2024 Springer-Verlag, New York.Ĭarpenter, P.W. IUTAM on Turbulence Management and Relaminarization, Bangalore (ed. (1987a) The optimization of compliant surfaces for transition delay. (1985) Hydrodynamic and hydroelastic stability of flows over non-isotropic compliant surfaces. (1984c) The hydrodynamic stability of flows over non-isotropic compliant surfaces. (1984b) A note on the hydroelastic instability of orthotropic panels. (1984a) The effect of a boundary layer on the hydroelastic instability of infinitely long plates. (1984) Differential eigenvalue problems in which the parameter appears nonlinearly. (1981) The upper branch stability of the Blasius boundary layer including nonparallel flow effects. (1963) The threefold classification of unstable disturbances in flexible surfaces bounding inviscid flows. (1960) Effects of a flexible boundary on hydrodynamic stability. (1959) Shearing flow over a wavy boundary. ![]() ![]() ![]() This may be stabilizing or destabilizing.īenjamin, T.B. In addition there is a weaker effect arising from the effect of anisotropic wall compliance on the phase shift across the wall layer. This almost invariably has a stabilizing effect on the travelling-wave flutter. For these walls an important mechanism for irreversible energy transfer is the work done by fluctuating shear stress. Viscous effects are much more important for anisotropic compliant walls which admit substantial horizontal, as well as vertical, displacement. The theory elucidates the secondary role played by the phase shift occurring across the wall layer. For isotropic compliant walls the theory confirms the earlier result of Miles and Benjamin that the phase shift in the disturbance velocity across the critical layer plays a dominant role in destabilization of the Class B travelling-wave flutter through making irreversible energy transfer possible due to the work done by the fluctuating pressure at the wall. The computational requirements are trivial compared with those required for full numerical solution of the Orr-Sommerfeld equation. Eigenvalues are very accurately predicted by means of the theory, especially near points of neutral stability. The disturbances can be treated as either temporally or spatially growing. The theory is applied to various cases including two- and three-dimensional disturbances, developing in boundary layers over isotropic and anisotropic compliant walls. Accordingly, the theory also gives a reliable qualitative guide to the effect of anisotropic wall compliance on the Tollmien-Schlichting instability. Under certain limiting processes both the upper-branch and conventional triple-deck scalings for the Tollmien-Schlichting instability can be obtained with the present approach. The theory was developed to study the travelling-wave flutter instability discussed by Carpenter and Garrad, i.e., the Class B instability of Benjamin and Landahl. ![]() The main assumptions are that the amplitude of the disturbance is sufficiently small for linear theory to hold, the Reynolds number is large, the disturbance wavelength is long compared with the boundary-layer thickness, and the critical and viscous wall layers are well separated. These quantities can be regarded as driving the wall and, accordingly, the equation(s) of motion for the wall is (are) used as the characteristic equation(s) for finding the eigenvalue(s). The theory exploits the multideck structure of the boundary layer to derive asymptotic approximations at a high Reynolds number for the perturbation wall pressure and viscous stresses. An asymptotic theory is developed for two- and three-dimensional disturbances growing in a two-dimensional boundary layer over a compliant wall.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |