A few additional data from our previous experiments were plotted to emphasize the shear-thickening behavior ofdeoxy sickle erythrocyte （SS） suspension. A constitutive equation （named as FX equation） was developed ...A few additional data from our previous experiments were plotted to emphasize the shear-thickening behavior ofdeoxy sickle erythrocyte （SS） suspension. A constitutive equation （named as FX equation） was developed and applied to a cylindrical pipe flow of a shear-thickening fluid. A blunt velocity profile and its volume flow rate were calculated. The flow was non-viscous （potential） in the central part of the pipe （i.e. the central core or the central plug-flow）, and became more and more viscous towards the wall of the pipe after a specific radial distance, which was determined by a critical shear rate of γF （named as Fung＇s shear rate）. Furthermore, combining the FX equation with the original Casson＇s equation, the author obtained a modified Casson＇s equation by introducing γF.展开更多
Projectile perforation of concrete slabs will produce numerous concrete fragments on the rear face of the concrete slabs. These concrete fragments will cause serious secondary damage to the indoor personnel and equipm...Projectile perforation of concrete slabs will produce numerous concrete fragments on the rear face of the concrete slabs. These concrete fragments will cause serious secondary damage to the indoor personnel and equipment of protective structures.Accurately evaluating the damage area of concrete slabs is an important problem. Therefore, a theoretical model of a rigid projectile perforation of concrete slabs is constructed using the energy method in this paper. In this model, a new shear failure method is proposed to calculate the energy consumption of the shear formation by combining with the von-Mises failure criterion and failure strain. Based on the energy conservation and principle of minimum potential energy, explicit equations for the perforation performance are formulated. The theoretical predictions agree well with the experimental results. Furthermore,experiments on a high-speed projectile normal perforation of concrete are carried out to verify the accuracy of the corresponding theoretical prediction.展开更多
文摘A few additional data from our previous experiments were plotted to emphasize the shear-thickening behavior ofdeoxy sickle erythrocyte （SS） suspension. A constitutive equation （named as FX equation） was developed and applied to a cylindrical pipe flow of a shear-thickening fluid. A blunt velocity profile and its volume flow rate were calculated. The flow was non-viscous （potential） in the central part of the pipe （i.e. the central core or the central plug-flow）, and became more and more viscous towards the wall of the pipe after a specific radial distance, which was determined by a critical shear rate of γF （named as Fung＇s shear rate）. Furthermore, combining the FX equation with the original Casson＇s equation, the author obtained a modified Casson＇s equation by introducing γF.
基金supported by the National Natural Science Foundation of China(Grant Nos.11390362&11521062)
文摘Projectile perforation of concrete slabs will produce numerous concrete fragments on the rear face of the concrete slabs. These concrete fragments will cause serious secondary damage to the indoor personnel and equipment of protective structures.Accurately evaluating the damage area of concrete slabs is an important problem. Therefore, a theoretical model of a rigid projectile perforation of concrete slabs is constructed using the energy method in this paper. In this model, a new shear failure method is proposed to calculate the energy consumption of the shear formation by combining with the von-Mises failure criterion and failure strain. Based on the energy conservation and principle of minimum potential energy, explicit equations for the perforation performance are formulated. The theoretical predictions agree well with the experimental results. Furthermore,experiments on a high-speed projectile normal perforation of concrete are carried out to verify the accuracy of the corresponding theoretical prediction.
