Studies on vibration of some rib-stiffened cantilever plates

The vibrational mode shapes and frequencies of rib-stiffened skew cantilever plates as determined by holographic interferometry are given. The effects of varying the sweep back angle, rib stiffness and aspect ratio are studied along with the influence of varying the boundary conditions at the root chord on the vibrational behavior of the plates. The study is applicable to investigating the vibrational behavior of stiffened plates often used in the design of guided rockets and missiles

Thermal stresses around an insulated crack in an infinite plate subjected to a uniform heat flow

In an earlier analysis Sih [1] presented a solution for stresses around the tip of an insulated arbitrary crack in an infinite thin plate subjected to a uniform heat flow using the complex variable method. Solutions obtained by Florence and Goodier [2] to the problem of an insulated elliptic hole in a similar plate subjected to a uniform hear flow provided the basis for the crack solution

Solutions to heat-conduction problems by a mixed method

A mixed formulation for the three-dimensional analysis of steady heat-conduction problems is presented. The method developed permits prescription of the boundary conditions in terms of either the temperature or the heat flux, or a combination of both. The general expressions for the temperature and the heat fluxes are derived in the form of a series in powers of the linear partial differential operators which operate on a set of initial functions to be determined by the prescribed boundary conditions. One of the important features of this method is its ability in providing approximate solutions in closed form. In order to illustrate the procedure some representative example problems with respect to thick plates have been solved, the corresponding solutions leading to results of engineering accurac

Thermal stresses around an elliptic hole in an infinite thick plate subjected to a uniform heat flow

A theoretical three-dimensional analysis is presented for determining the state of thermal stresses around an insulated13; elliptic hole in an infinitely long thick plate subjected to a uniform heat flow. The maximum stress is found to depend on13; the ratio of thickness to length of the semi-major axis of the hole and also on Poisson's ratio. In the limiting cases, the solution13; reduces to the corresponding circular hole solution obtained by Lee, and also to the two-dimensional solution of the13; elliptic hole problem as given by Florence and (;oodier

Stress concentration around an elliptic hole in a cylindrical shell under torsion with major axis of the hole perpendicular to the shell axis

In an earlier[1]2 a theoretical analysis was presented for the stresses around a small elliptic hole in an infinitley long cylindrical shell under torsional loading with the major axis of the hole parallel to the shell axis .In the limiting case the solution reduced to that of an axial crack.The purpose of this Note is to examine axis lying parallel to the shell axis .In the limiting case the solution reduces to that corresponding to a circumferential crack

Stress analysis of a compressor assembly subjected to mechanical and thermal loadings

The state of elastic stresses in a seven stage compressor disk drum rotor assembly subjected to mechanical and thermal loadings is investigated. The stress analysis is carried out by using the finite element technique employing the displacement method. A consistent technique is derived in order to discretize distributed surface loadings, centrifugal and thermal loadings. A general computer program in Fortran language which can take into account the variation of material properties due to temperature variations has been written for calculating stresses and deflections due to various loadings. Some numerical examples for which solutions are available by exact methods are presented to substantiate various proposed procedures. Numerical results for the stresses and deflections at a few selected points in the compressor assembly obtained in respect of a few grid idealizations are also presented and their accuracy discussed