It is important to understand the characteristics of explosive sympathetic detonation for explosive safety.Sympathetic reaction test of GHL(RDX/Al/Binder)explosive charges with shell are conducted.A model of the sympa...It is important to understand the characteristics of explosive sympathetic detonation for explosive safety.Sympathetic reaction test of GHL(RDX/Al/Binder)explosive charges with shell are conducted.A model of the sympathetic reaction test is established.The elements-apart method and nodes random-failure method are used in the model to describe the expansion progress of shell expanding and the randomly forming process of fragments.Random detonation phenomena of acceptor charge are simulated.展开更多
A Direct Numerical Simulation (DNS) scheme for solving the temporal-spatial multiscale problem of sympathetic detonation is proposed. According to the physical and chemical properties, the SD process is divided into t...A Direct Numerical Simulation (DNS) scheme for solving the temporal-spatial multiscale problem of sympathetic detonation is proposed. According to the physical and chemical properties, the SD process is divided into two stages in the numerical simulation. Two different grid sizes are used in the two stages to improve calculation accuracy and efficiency. The local Level Set Method is used to accurately track the multi-material interface, and the Harten Lax and van Leer Contact (HLLC) method is used to solve local Riemann problem. Based on the computing method mentioned above, choosing the high evolution Weighted Essentially Non-Oscillatory (WENO) scheme for the spatial discretization of governing equations in alliance with Total Variation Diminishing (TVD) Runge-Kutta for time discretization, the Eulerian code of SD is developed. It solves the data interaction between the two solvers with variable grid size and time step, and realizes the three-dimensional parallel computing of SD. Composition B is taken as the research object. The processes of SD in different stand-off distances are analyzed. The transmission and safety distances of Composition B are given. The test under the same conditions is designed to verify the numerical simulation. The numerical simulation results are in good agreement with the experiment, which proves the accuracy and feasibility of the numerical method.展开更多
The study was to investigate the effect of reducing central sympathetic nervous tone with clonidine on cardiomyocyte contraction,and further to analyze the influence of reducing the central sympathetic nervous tone on...The study was to investigate the effect of reducing central sympathetic nervous tone with clonidine on cardiomyocyte contraction,and further to analyze the influence of reducing the central sympathetic nervous tone on response of β1 and β2-AR in aged ventricular myocytes.Sprague-Dawley rats were randomly divided into three groups:adult group,aged group and aged group with clonidine.展开更多
文摘It is important to understand the characteristics of explosive sympathetic detonation for explosive safety.Sympathetic reaction test of GHL(RDX/Al/Binder)explosive charges with shell are conducted.A model of the sympathetic reaction test is established.The elements-apart method and nodes random-failure method are used in the model to describe the expansion progress of shell expanding and the randomly forming process of fragments.Random detonation phenomena of acceptor charge are simulated.
基金This work was supported by the National Natural Science Foundation of China[11732003,U1830139].
文摘A Direct Numerical Simulation (DNS) scheme for solving the temporal-spatial multiscale problem of sympathetic detonation is proposed. According to the physical and chemical properties, the SD process is divided into two stages in the numerical simulation. Two different grid sizes are used in the two stages to improve calculation accuracy and efficiency. The local Level Set Method is used to accurately track the multi-material interface, and the Harten Lax and van Leer Contact (HLLC) method is used to solve local Riemann problem. Based on the computing method mentioned above, choosing the high evolution Weighted Essentially Non-Oscillatory (WENO) scheme for the spatial discretization of governing equations in alliance with Total Variation Diminishing (TVD) Runge-Kutta for time discretization, the Eulerian code of SD is developed. It solves the data interaction between the two solvers with variable grid size and time step, and realizes the three-dimensional parallel computing of SD. Composition B is taken as the research object. The processes of SD in different stand-off distances are analyzed. The transmission and safety distances of Composition B are given. The test under the same conditions is designed to verify the numerical simulation. The numerical simulation results are in good agreement with the experiment, which proves the accuracy and feasibility of the numerical method.
文摘The study was to investigate the effect of reducing central sympathetic nervous tone with clonidine on cardiomyocyte contraction,and further to analyze the influence of reducing the central sympathetic nervous tone on response of β1 and β2-AR in aged ventricular myocytes.Sprague-Dawley rats were randomly divided into three groups:adult group,aged group and aged group with clonidine.
