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Splined shaft torsional analysis by construction of conformal mapping function with Schwarz- Christoffel transformation, noting shear stress distribution and reentrant corners
Solid sphere transient thermal stress distribution analyzed by scattered light photoelasticity
Geometrically exact finite element for thin shells of revolution, using approximation to predict boundary layer stress distribution during vibration
Transient temperature profiles and thermal stress distribution in circular plates and cylinders with eccentric hole determined by conformal mapping
Viscoelasticity in shearing and accelerative flows by integral theory, discussing stress distribution and pressure drop
Geometrically exact finite element for thin shells of revolution, using approximation to predict boundary layer stress distribution during vibration
Plate thickness effect on stress distribution around crack, using three dimensional elasticity equations
Seasonal and annual longitudinal variations in ionospheric ion distribution, stressing solar geomagnetic control importance
Thermal stress distribution and temperature profiles in nearly opaque spherical shell under radiant and convective heating flux
Elastic and damping analyses resulting in determinations of the various stiffnesses and associated loss tangents for the complete characterization of the elastic and damping behavior of a monofilament composite layer are presented. For the determination of the various stiffnesses, either an elementary mechanics-of-materials formulation or a more rigorous mixed-boundary-value elasticity formulation is used. The solution for the latter formulation is obtained by means of the boundary-point least-square error technique. Kimball-Lovell type damping is assumed for each of the constituent materials. For determining the loss tangents associated with the various stiffnesses, either the viscoelastic correspondence principle or an energy analysis based on the appropriate elastic stress distribution is used.
Nonlinear boundary value problems of an infinite elastic-plastic plate with a circular hole subjected to pure tension and pure shear at infinity are solved by a method involving Fourier series and finite difference. On the basis of these solutions, the validity of Neuber's relationship between the stress and strain concentration factors for the plane stress problems is examined and a generalized Stowell formula for the stress concentration factor is proposed for problems in which the applied loading may be pure shear as well as pure tension and, furthermore, other stress states. By the same method of solution, the stress distributions around a rigid circular cylindrical inclusion embedded in an infinite rigid-plastic matrix subjected to uniform transverse pure shear and tension are obtained.
A predictive method for the titled flows based on the Prandtl energy method was developed and assessed by comparing predicted results with experimental results. For constant-density flows, both gross properties such as spreading rate and maximum turbulent kinetic energy and detailed properties such as mean shear stress distributions are shown to be well predicted. For variable-density flows, considerable attention is devoted to the inclusion in the analysis of the added effect of pressure fluctuations and of the variation in the several extant empirical parameters on the turbulent kinetic energy. It is found that a variation with Mach number of the characteristic Reynolds number for turbulent transport is needed to account for the observed decrease in spreading rate. The predictions which result from these considerations are compared with the limited experimental data presently available for the two crucial cases: compressible adiabatic mixing and low-speed isothermal mixing of two dissimilar gases.
By discarding Lurie's (1952) assumption of mode identity, it is shown that linear theory correctly predicts the frequency of all modes of a thermally stressed cantilever plate as well as the frequency and modes of plates with other boundary conditions. The thermal stress distribution is obtained for whatever temperature distribution and boundary conditions that may be specified. Experimental results are compared to calculated results for several different plates. Boundary conditions for the plates range from a plate with edges completely clamped to a plate with edges completely free with various other combinations of mixed and uniform edge conditions. Comparison of calculated data to experimental data shows that accurate, quantitative results can be obtained from linear theory for 'as cut' real plates for a significant range of heating when the assumption of mode identity is discarded.
A quantitative study of internal torsion in the entire tibial bone was performed by using strain gauges to measure the amount of deformation occuring at different locations. Comparison of strain measurements with physical dimensions of the bone produced the modulus of rigidity and its behavior under increased torque. Computerized analysis of the stress distribution shows that more strain occurs near the torqued ends of the bones where also most of the twisting and fracturing takes place.
An analysis of turbulent boundary layer flow characteristics and the computational procedure used are discussed. The integrated mass and momentum flux profiles and differentials of the integral quantities are used in the computations so that local evaluation of the streamwise velocity gradient is not necessary. The computed results are compared with measured shear stress data obtained by using hot wire anemometer and laser velocimeter techniques. The flow measurements were made upstream and downstream of an adiabatic unseparated interaction of an oblique shock wave with the turbulent boundary layer on the flat wall of a two dimensional wind tunnel. A comparison of the numerical analysis and actual measurements is made and the effects of small differences in mean flow profiles on the computed shear stress distributions are discussed.
The elastic deformation of two ellipsoidal solids in contact and subjected to Hertzian stress distribution was evaluated numerically as part of a general study of the elastic deformation of such solids in elastohydrodynamic contacts. In the analysis the contact zone was divided into equal rectangular areas, and it was assumed that a uniform pressure is applied over each rectangular area. The influence of the size of the rectangular area upon accuracy was also studied. The results indicate the distance from the center of the contact at which elastic deformation becomes insignificant.
Finite element computer analyses of the reinforcement of cutouts and cracks in metal sheet by bonded overlays of composite material are described. The analyses articulate the separate responses of the sheet, the overlays, and the adhesive. Contour plots of computed stress and strain fields are automatically generated by the computer programs. Strains measured on the surfaces of several reinforced-sheet tensile specimens were, for the most part, in good agreement with strains predicted by the analyses. Significant correlations between certain failure modes observed in the test specimens and the stress distributions given by finite element analysis are apparent.
The elastic deformation of two ellipsoidal solids in contact and subjected to a Hertzian stress distribution was evaluated numerically as part of a general study of the elastic deformation of such solids in elastohydrodynamic contacts. In the analysis the contact zone is divided into equal rectangular areas and it is assumed that a uniform pressure is applied over each rectangular area. A study was made of the influence on the size of the rectangular area upon accuracy. The results also indicate how far from the center of the contact one needs to go before elastic deformation becomes insignificant.