Computation of Onset and Growth of Delamination in Double Cantilever beam Specimens Subjected to Fatigue Loading

In this article, the delamination onset and growth behavior of double cantilever beam (DCB) specimens has been presented. The modeling of a debonded region using master and slave surface technique for DCB specimens is done in ABAQUS CAE. The analysis of DCB specimens comprising of fatigue cyclic load has been done in ABAQUS. An onset and Paris delamination growth regimes are plotted. The growth regime being linear in log-log scale, the prediction of constants of this regime has been obtained using the polyfit command in the MATLAB environment. To obtain these constants has been explained in this article. Comparison of experimental and analytical results is shown for delamination growth. The strain energy release rate values for threshold and critical are indicated on the graphs. The number of cycles for delamination onset and growth has been tabulated for various load cases.Defence Science Journal, Vol. 64, No. 4, July 2014, pp. 400-405, DOI:http://dx.doi.org/10.14429/dsj.64.4069

Crack growth simulation of stiffened fuselage panels using XFEM techniques

418-428In this paper, crack growth modelling and simulation of stiffened and un-stiffened fuselage panels has been presented using commercially available finite element software package. Computation of stress intensity factor for a single edge notch specimen has been computed using extended finite element method (XFEM), FEM and compared with the analytical solution. The geometric nonlinear and elastic-plastic (material nonlinear) analysis has been performed on a specimen, stiffened and un-stiffened fuselage panels. XFEM techniques like cohesive segment and XFEM based LEFM using virtual crack closure technique (VCCT) are used for crack growth analysis. Various crack domain selection and parametric studies of stiffener thickness are presented. It is observed from the numerical analyses that the stiffened panels have about 20% higher yield strength compared to the un-stiffened panel. </span

A study on electrical resistance and RSW characterizaton of bimetal wire

The objective of this study is to reduce copper consumption in Solenoid of Circuit breaker by using aluminium with copper technically called copper clad aluminium. Aluminium wires with copper clad are widely used, e.g. in telecommunication, power engineering, electronics as a replacement of traditional applied copper wire. The reason is that the properties of these bimetal wires combine the smaller density and low cost. This study investigates the effect of tripping properties in Circuit breaker thru various magnetic testing methods. Magnetic testing and an experiment verified the tripping threshold depends on the Copper and aluminium combination ratio