Prediction Of Damage And Failure Of Gas-Filled Pressure Vessels Under Space Debris Hypervelocity Impact

With the unceasing development of space activity, the total number of space debris is ever increasing, which greatly threatens orbiting space vehicles. Spacecraft often employ pressure vessels to contain gases and liquids. A pressure vessel subjected to hypervelocity impact by meteoroids and space debris can represent a significant hazard to a space vehicle because of the energy stored within the vessel. Vessel can occur venting through the impact hole. Catastrophic rupture of the vessel can send high-velocity fragments in all directions and secondary debrisary damage becomes a serious threat to the spacecraft. The damage characteristic of pressure vessel by space debris and prediction of catastrophic failure are the important basic of shield structure design and risk evaluation of spacecraft in space debris environment.At present, the quantitative investigation on damage process of pressure vessel under hypervelocity impact is still very limit. Systemic prediction model for damage and failure of pressure vessels under hypervelocity impact has not built.Based on the background mentioned above, this paper investigates the damage process of pressure vessel under hypervelocity impact. The impact velocity is ranging from 1.0 km/s to 7.0 km/s, the impact condition limits to fragmentation and melt of materials. The gas-secondary debris interaction process and propagation process of shock wave are investigated, and the prediction model for damage and failure of pressure vessels under hypervelocity impact is built.Lagrange methods in AUTODYN-2D is used for investigate the relationships between impact hole size, crack size, gas pressure and impact conditions. According to characteristics of impact hole, initial model of secondary debris is built. The model is presented by postulates the existence of two-radial cracks that emanate at the boundary of a circular hole. The relationships of impact hole size, crack size, gas pressure and the stress intensity factor which is determined by simplified linear elastic fracture mechanics are obtained. The damage process of the front wall is analyzed. The prediction model for damage and failure of front wall is built. The critical stress value is obtained.SPH methods in AUTODYN-2D is used for investigate the gas-secondary debris interaction process. The numerical simulation results are consistent with experimental results very well. The fragmentation process of projectile is introduced. According to characteristic of secondary debris, initial model of secondary debris is built. The gas-secondary debris interaction process is analyzed. The model of the gas-secondary debris interaction is built. The calculational results are compared to experimental results to verify the usefulness of the model. The motion characteristics of secondary debris and the rules of shock wave propagation are obtained.the paper assumes that the rear wall is subjected to uniform load when impacted by the debris cloud and shock wave. Initial velocity of the rear wall under a localized pulse loading is obtained. Based on the closed from deflection solution for thin plates subjected to localize explosive loading, the radius of discing and petalling is obtained. The prediction model for damage and failure of rear wall is built. The critical condition of catastrophic rupture of rear wall under a localized gas pressure is obtained.Last, based on the previous study, the prediction model for damage and failure of pressure vessels under hypervelocity impact is built. The applicable scope of prediction model is discussed. The calculational results are compared to experimental results to verify the usefulness of the model. The paper gives the prediction process.The result of this paper has some significant meanings and is valuable in engineering applications and providing theoretical guidelines. It reveals the physical process of pressure vessel damage and mechanism of damage. It provides technical foundation for risk assessment of pressure vessel and shielding design applications of pressure vessel.