Laser Irradiated Metal Cylindrical Shells With Explosives To Heat Up The Numerical Simulation Of The Process

The instantaneous nonlinear temperature field of the metallic cylindrical shell filled with explosive under laser irradiation is simulated and analyzed by using the program of finite element method, and the theories of Maxwell's equations and the first law of thermodynamics. In the simulation, thermo-physical properties varying with temperature are considered. The phase change of the metallic cylindrical shell and explosive is considered by defining the enthalpy of the material as a function of temperature in the simulating. Under the condition of the same output power, when the size of facula is changed, the corresponding influence of the material temperature is analyzed. And the heat transfer of explosive and the possibility of thermal initiation of explosive are also discussed.Two factors effecting on the temperature distribution of the metallic cylindrical shell and explosive are discussed by studying the nonlinear heat transfer under laser irradiation. First, the temperature field is simulated at the condition that the absorption coefficient of material change with temperature under laser interaction by using the heat generation, and then the temperature field is analyzed when the absorption coefficient of the materials is constant. The results indicate that the influence of temperature field is no longer neglected due to the variation of absorption coefficient of materials. Second, the coupled effect of the Thermal-stress field is considered. The temperature field and the Thermal-stress field of the metallic hollow cylinder are simulated. The results show that the higher of the laser power density, the more obvious of effect of the heat transfer in the Thermal-stress coupled field. The physical figures of thermal deformation at several times are illustrated, and the equal stress is also analyzed.