D.K.L. Tsang

Multiple penny-shaped cracks interaction in a finite body and their effect on stress intensity factor

In this paper we investigate the stress intensity factors (SIFs) of multiple penny-shaped cracks in an elastic solid cylinder under mode I (axial tension) loading. The cracks are located symmetrically and in parallel to one another in the isotropic cylinder. The fractal-like finite element method (FFEM) is employed to study the interaction of multiple cracks and to demonstrate the efficiency of the FFEM for multiple crack problems. The results show that the SIF values of the inner cracks, which are denoted as crack number 1; 2; 3; ... ; ðn þ 1Þ=2 of a stack of n parallel cracks, are lower than the SIF values of a single crack by between 16% and 48%. Also, the outermost crack, that is the crack closest to the boundaries of a multiple cracked body, has the highest SIF values and is, therefore, likely to fail first. 2002 Elsevier Ltd. All rights reserved.

A numerical study of a detonation wave in detonation transmission tubing

In this paper we formulate a one-dimensional detonation wave model for detonation transmission tubing. The reaction is described by a temperature-independent single-step kinetic equation and the resulting equations are a system of hyperbolic conservation laws. The initial boundary value problem is then solved by using the TVD MacCormack method. The effects of heat loss to the tube wall and of the tube expansions have also been considered. The result obtained shows that the heat loss and the tube expansion have a major effect on the pressure prediction.