The current body armor systems manufactured using ballistic fibers are not performing as theoretical results predict and are causing injuries. The actual maximum projectile penetration speed that the body armor can endure is significantly lower than the theoretical maximum speed, thus causing a costly build-test relationship that is not aided with modeling design efforts. The main aim of this r...

Formulations for a general theory of thermoelasticity to generate accurate thermal stresses for structural members of aeronautical vehicles were developed in 1954 by Boley. The formulation also provides three normal stresses and a shear stress along the entire length of the beam. The Poisson effect of the lateral and transverse normal stresses on a thermally loaded beam is taken into account in...

Cyclic-tension fatigue of aluminum alloy, Al-4Cu-1Mg, was determined by an analysis of diffracted SH and SV waves, passing through the surface and reflecting the bottom of the specimen, respectively. The internal friction of SV waves begins to increase from fatigue damage ratio(=N/Nf) of 0.5. This suggests increase of movable dislocation. From the analysis of SH waves, the logarithmic damping r...

The classical shell theory, first-order shear deformation theory, and third-order shear deformation theory are employed to study the natural frequencies of functionally graded cylindrical shells. The governing equations of motion describing the vibration behavior of functionally graded cylindrical shells are derived by Hamilton’s principle. Resulting equations are solved using the Navier-type s...

We use the lubrication approximation to investigate the steady flow of slender non-uniform rivulets of a viscous fluid on an inclined plane that is either heated or cooled relative to the surrounding atmosphere. Four non-isothermal situations in which thermocapillary effects play a significant role are considered. We derive the general equations for a slender rivulet subject to gravity, surface...

Two new families of Reissner-Mindlin triangular finite elements are analyzed. One family, generalizing an element proposed by Zienkiewicz and Lefebvre, approximates (for k ≥ 1) the transverse displacement by continuous piecewise polynomials of degree k + 1, the rotation by continuous piecewise polynomials of degree k+ 1 plus bubble functions of degree k+ 3, and projects the shear stress into th...

The study presents results of computer simulation by finite elements method a new metal forming process combining the deformation billet with round cross-section on radial-shear rolling mill and subsequent twisting in die specific design. To analyze efficiency processing, main parameters stress–strain state are considered: effective strain, stress, average hydrostatic pressure, Lode–Nadai coeff...

Elastic plates can be described by a two-dimensional theory, if the characteristic length of the stress state along the plate, l; is much bigger than the plate thickness, h: If all elastic moduli of a laminated plate are of the same order, no matter how many lamina the plate has, then the normal to the mid-surface of the plane remain normal in the course of deformation, and the deformation of t...