Flutter of panels on discrete flexible supports

The supersonic flutter of wide panels on discrete flexible supports is investigated for three different panel-support configurations. The first study examines the effect of support stiffness on the flutter behavior of a specific five-support configuration with leading-and trailing-edge overhangs; this configuration was recently under consideration for a heat shield on an entry body. The second study investigates the effect of support stiffness on flutter of panels with various numbers of equally spaced supports. The third study examines the effect of center-support location on the flutter of panels with three supports. Results are presented in nondimensional form. The analysis is based on wide-plate structural theory and Ackeret aerodynamics. Finite differences are employed to obtain solutions for flutter pressure. A computer program based on this analysis and including a direct solution technique is presented. The program can be used to find the flutter pressure of wide panels of variable thickness supported by any number of flexible supports

A solution procedure for behavior of thick plates on a nonlinear foundation and postbuckling behavior of long plates

Approximate solutions for three nonlinear orthotropic plate problems are presented: (1) a thick plate attached to a pad having nonlinear material properties which, in turn, is attached to a substructure which is then deformed; (2) a long plate loaded in inplane longitudinal compression beyond its buckling load; and (3) a long plate loaded in inplane shear beyond its buckling load. For all three problems, the two dimensional plate equations are reduced to one dimensional equations in the y-direction by using a one dimensional trigonometric approximation in the x-direction. Each problem uses different trigonometric terms. Solutions are obtained using an existing algorithm for simultaneous, first order, nonlinear, ordinary differential equations subject to two point boundary conditions. Ordinary differential equations are derived to determine the variable coefficients of the trigonometric terms

The Future of Social Justice in Britain: A New Mission for the Community Legal Service

This paper explores the disjuncture in the New Labour Government between the largest reform in fifty years of the nation's Legal Aid system and the concurrent pursuit of progressive anti-poverty, social inclusion, community regeneration, and human rights social policies. The failure of the newly created Community Legal Service (CLS) to incorporate these policies reveals the contradictions in the Third Way's effort to reconcile private market, managerial efficiencies with the goals of advancing social justice. This failure to adopt a social justice mission for the reformed legal aid and advice system, it is argued, shows the limited vision of these reforms and defines an unfinished agenda for a second term Labour Government. The paper suggests what would constitute a social justice mission for the CLS.legal aid, social justice, Community Legal Services

Numerical analysis and parametric studies of the buckling of composite orthotropic compression and shear panels

A computer program is presented which was developed for the combined compression and shear of stiffened variable thickness orthotropic composite panels on discrete springs: boundary conditions are general and include elastic boundary restraints. Buckling solutions are obtained by using a newly developed trigonometric finite difference procedure which improves the solution convergence rate over conventional finite difference methods. The classical general shear buckling results which exist only for simply supported panels over a limited range of orthotropic properties, were extended to the complete range of these properties for simply supported panels and, in addition, to the complete range of orthotropic properties for clamped panels. The program was also applied to parametric studies which examine the effect of filament orientation upon the buckling of graphite-epoxy panels. These studies included an examination of the filament orientations which yield maximum shear or compressive buckling strength for panels having all four edges simply supported or clamped over a wide range of aspect ratios. Panels with such orientations had higher buckling loads than comparable, equal weight, thin skinned aluminum panels. Also included among the parameter studies were examinations of combined axial compression and shear buckling and examinations of panels with rotational elastic edge restraints