NUMERICAL SIMULATION OF MECHANICAL BEHAVIORS OF SUPERCONDUCTING POWDER BSCCO （BiSrCaCuO）

An equivalent continuum method and a deformable discrete method to describe the mechanical behaviors of superconducting powder BSCCO (BiSrCaCuO) aggregate are studied syste-matically. The equivalent continuum model idealizes the aggregation of the powder as an equivalent continuum material. The powder aggregate yielding is caused by not only the deviatoric stress but also the hydrostatic stress and the modified Drucker-Prager/Cap model is adopted to describe the mechanical behaviors of BSCCO powder aggregate in continuum method. The deformable discrete model is known as a direct model, which considers the discrete nature of the powder particles. Its framework encompasses the local behaviors between the particles, such as particles contact, sliding and rolling. Based on commercial finite element software ABAQUS, the equivalent continuum model and the deformable discrete model are used to simulate the confined compression of superconducting powder BSCCO, and the numerical results show agreement with experimental results, which verify the correctness of these built models. Compared with the equivalent continuum model based on macroscopic statistics method, the deformable discrete model can present the microscopic information during processing and can describe the nature of mechanical behaviors of superconducting powder BSCCO. But from an industrial viewpoint, the equivalent continuum model has a definitive edge over the microscopic models in that the gross behavior of the powder mass can be modeled and simulated on an industrial scale.

NUMERICAL SIMULATION OF MECHANICAL BEHAVIORS OF SUPERCONDUCTING POWDER BSCCO (BiSrCaCuO)

An equivalent continuum method and a deformable discrete method to describe the mechanical behaviors of superconducting powder BSCCO (BiSrCaCuO) aggregate are studied systematically. The equivalent continuum model idealizes the aggregation of the powder as an equivalent continuum material. The powder aggregate yielding is caused by not only the deviatoric stress but also the hydrostatic stress and the modified Drucker-Prager/Cap model is adopted to describe the mechanical behaviors of BSCCO powder aggregate in continuum method. The deformable discrete model is known as a direct model, which considers the discrete nature of the powder particles. Its framework encompasses the local behaviors between the particles, such as particles contact, sliding and rolling. Based on commercial finite element software ABAQUS, the equivalent continuum model and the deformable discrete model are used to simulate the confined compression of superconducting powder BSCCO, and the numerical results show agreement with experimental results, which verify the correctness of these built models. Compared with the equivalent continuum model based on macroscopic statistics method, the deformable discrete model can present the microscopic information during processing and can describe the nature of mechanical behaviors of superconducting powder BSCCO. But from an industrial viewpoint, the equivalent continuum model has a definitive edge over the microscopic models in that the gross behavior of the powder mass can be modeled and simulated on an industrial scale.