H.A. Richard¹, M. Fulland², G. Kullmer¹, N.-H. Schirmeisen¹

Structural Durability & Health Monitoring, Vol.6, No.3&4, pp. 161-188, 2010, DOI:10.3970/sdhm.2010.006.161

Abstract Fracture processes in real structures are in many cases of a three dimensional (3D) character. In this paper some basic problems of 3D-fracture processes are considered and discussed, in particular for general mixed-mode loading conditions, when modes I and II and III are superimposed. For experimental investigations an AFM-specimen is under consideration, while numerical simulations are carried out with the program ADAPCRACK3D. More >

X.P. Shen¹, J.L. Feng²

CMC-Computers, Materials & Continua, Vol.20, No.2, pp. 185-204, 2010, DOI:10.3970/cmc.2010.020.185

Abstract The characteristic length of a gradient-dependent damage model is a key parameter, which is usually regarded as the length of damage process zone (DPZ). Value and evolution of the size of DPZ were investigated by both a numerical method and an experimental manner. In the numerical study, the geometrical model adopted was a set of four-point shearing beams; the numerical tool used was the Abaqus/Explicit software. The distance between the front and end of a complete DPZ was obtained. Values of strain components at these points were given out at given time points. The experimental… More >

Jong-Kook Cha¹, Jin-Rae Cho¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.3, pp. 129-134, 2008, DOI:10.3970/icces.2008.007.129

Abstract Sloshing flow is formulated based on the linearized potential flow theory, while an artificial damping term is employed into the kinematic free-surface condition to reflect the eminent dissipation effect in resonant sloshing. Through the numerical analysis of sloshing frequency response with respect to the number, location and opening width of baffle, the sloshing damping characteristics by baffle are parametrically investigated. More >

J. Kato¹, K. Inaba², M. Yamamoto³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.1, pp. 25-30, 2007, DOI:10.3970/icces.2007.004.025

Abstract Pulse detonation turbine engines (PDTEs), which are used as power generation, are desirable to use hydrocarbon from the aspect of infrastructure of fuels. In the present study, we investigate the performance of PDEs using mixed hydrocarbon fuels. With the detailed 42-species and 168-step mechanism, numerical simulations on mixed-fuel-and-air PDEs are conducted. We use CH4-C3H8, CH4-H2, and C3H8-H2 as fuels, and examine characteristic features of detonations with different blend ratios. We perform calculations on the Chapman-Jouguet detonation speeds and chemical reaction lengths, and investigate ZND profiles of chemical reactions. Then we evaluate PDEs performances by changing More >

T. Nishioka¹, S. Tchouikov¹, T. Fujimoto¹

CMC-Computers, Materials & Continua, Vol.3, No.3, pp. 147-154, 2006, DOI:10.3970/cmc.2006.003.147

Abstract In this study, phenomena of multiple branching of dynamically propagating crack are investigated numerically. The complicated paths of cracks propagating in a material are simulated by moving finite element method based on Delaunay automatic triangulation (MFEM BODAT), which was extended for such problems. For evaluation of fracture parameters for propagating and branching cracks switching method of the path independent dynamic J integral was used. Using these techniques the generation phase simulation of multiple dynamic crack branching was performed. Various dynamic fracture parameters, which are almost impossible to obtain by experimental technique alone, were accurately evaluated. More >

Xiaoming Wang¹, Philip L.-F. Liu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.10, No.2, pp. 171-184, 2005, DOI:10.3970/cmes.2005.010.171

Abstract On May 21, 2003 Boumerdes-Zemmouri (Algeria) earthquake generated a small tsunami, which was recorded at several locations around the coast of Balearic Islands, Spain. Recent field studies (Meghraoui, et al., 2004) and teleseismic wave analysis (Yiga, 2003) indicated that the earthquake magnitude is stronger than that suggested by the Harvard CMT solution. Moreover, the seafloor displacement is also not uniform along the rupture line. In this paper, we perform a numerical investigation to evaluate the accuracy of various suggested fault plane mechanisms. The numerical model is based on the shallow-water equations and numerical results are compared More >

J. H. Jackson¹, A. S. Kobayashi², S. N. Atluri³

CMES-Computer Modeling in Engineering & Sciences, Vol.6, No.1, pp. 17-30, 2004, DOI:10.3970/cmes.2004.006.017

Abstract The T_ε^*  integral was calculated numerically along an extending, tunneling crack front in an 8 mm thick, aluminum three-point bend (3PB) specimen, using a numerical model driven by experimentally obtained surface displacements. The model provided input to a contour integration for the T_ε^*  integral, via the Equivalent Domain Integral (EDI) method with incremental plasticity. Validity of the analysis was ensured by the agreement of the T_ε^*  integral obtained on the surface (plane stress) and the plane stress values from previous studies. T_ε^*   was observed to decrease from the outer surface of the specimen to More >

Wolfgang Brocks¹, Weidong Qi²

CMES-Computer Modeling in Engineering & Sciences, Vol.3, No.3, pp. 313-320, 2002, DOI:10.3970/cmes.2002.003.313

Abstract Results of a numerical study of creep damage development and its effect on the deformation behavior in the Ni-based superalloy IN 738 LC at 850 °C are reported. A continuum damage mechanics based anisotropic damage model has been coupled with the unified model of Chaboche, and is used for the present study. Numerical computations are performed on a plate containing a circular hole under tension. They show that the applied damage model does not cause damage localization and no significant mesh-dependence of the results are observed. More >