A Viscoelastic Statistic Crack Constitutive Model For Mechanical Response And The Non-shock Ignition Of High Explosives

This paper, which based on viscoelastic statistic crack model, considering frictional thermal of micro crack surface as a important factor which urges energetic materials igniting , describes a ignition model of a frictional thermal of micro crack surface .Shear distortion is simulated by impacting PBX-9501 high explosive with 26 m/s.The temperture,press and so on in PBX-9501 high explosive is solved.Temperture is simulated using solved strain rate and press based on frictional ignition model.By numerically simulation , effect of ignition-time of energetic materials upon positive stress,width of hotspots area,a rate of strain and so on is researched. Finally, change of temperature and so on is simulated when missile with high explosive invades steel barget and rationality of model is validated .The main innovation content can be summarized as:1.The literature review of constitutive models with frictional ignition model and viscoelastic statistic crack model of the energetic materials is conducted systematically and sufficiently.A ignition model of hotspots based on the general viscoelastic statistic crack model and a frictional ignition model on the micro crack are built.2.A user-defined frictional ignition model subroutine is finished. Effect of ignition-time of energetic materials upon positive stress,width of hotspots area,a rate of strain and so on is researched.3.The dynamic cutting experiment of confined PBX-9501 high explosive is numerically simulated using LS-DYNA solver compiled and built. Change of the temperature,press and so on is given. Results are evaluated based on frictional ignition model under the condition of given press and strain rate.4.Change of the temperature is simulated when a missile is invading steel barget and change of the temperature is solved. Compress of PBX-9501 high explosive results in increase of the temperature.