Development Of The Multi-scale Simulation System For Mechanical Properties Of Energetic Materials

Numerical simulation is an important method to study the mechanical properties of energetic materials. Of all the commonly used simulation software, molecular dynamics simulation can simulate the related properties of energetic materials in molecular level. However, due to the limitation of computational resources, the molecular dynamics simulation is limited to the micro system. The material point method can be used to simulate the properties of energetic materials near particle level, but the method is still in the initial stage, and the application is not mature. Although the finite element method can be close to the macro scale of the project to study the properties of energetic materials, it cannot consider the microstructure of energetic materials, and the application effect of the method is poor. In recent years, multi-scale simulation method has been widely concerned, which can link the properties of materials in various scales, but there is no available software based on multi-scale simulation to use. It is urgent to develop convenient multiscale simulation software.The multi-scale simulation system for mechanical properties of energetic materials was designed and implemented based on step-by step simulation, which can compute the physical and mechanical properties in a stepwise manner to solve above problems. In the microscale computing module of the system, material properties, including the state equations of components and the constitutive relation of the viscoelastic material, were computed using molecular dynamics simulation method. These properties were then used as parameters in mesoscopic numerical simulation. In the mesoscopic computing module of the system, mechanical properties of energetic material were calculated by material point method, and the equation of state and the viscoelastic constitutive equation were ontained. In the macroscale computing module of the system, based on the mesoscopic calculation result, the mechanics properties of energetic materials were calculated using finite element method and compared with experimental results. This system could provide an effective tool to study mechanical properties of energetic material.This thesis focuses on the computing module in mesoscopic scale because the mature software is available to simulate in microcosmic and macroscopic scale. The mesoscopic model of energetic materials was established by approximate method. With the technology of accessing data oriented Java3 D virtual scene to access the three-dimensional virtual scene data, a scene could be reused in the modeling process. The data could be viewed in parallel condition by Vis It-based parallel visualization technology, which solved the problem that the data could not be displayed in high-performance visualization due to the limitation of computer resources in singal machine. Testing results showed that the system can respond within 1s, and run 5×24 hours with no interruption. The system response and stableness meet the design goals. The system will provide theoretical base for pressing technology of energetic materials, and offer a tool for improving and optimizing the quality of energetic materials.