Investigation On The Numerical Evaluation Methods For Ring/Disk Containment

The article is mainly concerned with disk fragment containment in ring structures.In order to investigate the ballistic resistance and failure pattern of the ring with the impact of disk fragments, and master the numerical simulation method, the phenomena of 1/3 disk fragment impacting on single and double layers plate target is simulated using nonlinear dynamic analysis software LS-DYNA. Simulation results show that the major failure patterns of the plate target include plastic deformation, shear and tensile fracture, and that the single layer plate has greater resistance than any other double-layered plates. The ballistic limit velocity increases with the distance when it is beyond a certain value, and greater resistance is obtained in low or high proportion of the first layer with a constant of the total thickness.To avoid disk failure uncontained accidents, disk fragment containment capability of the ring must be investigated by experiments, and the impact, deformation, penetration of the ring must be studied in detail. Three disk fragment containment tests show that failure modes of ring vary significantly as different wall thickness of the ring. Tearing, tensile fracture and large plastic deformation occur in thin wall ring, while large plastic deformation occur in thick wall ring. Numerical simulation are correspondingly carried out using LS-DYNA. The simulation results show a good agreement with the test results, which validates the feasibility of prediction of ring/disk containment capability and design new containment structures using simulation.Based on the ring/disk containment tests and corresponding simulation, a series of preliminary simulation are conducted for analyzing the factors that affect the containment capability of the ring. Some factors, including disk rotating speed, ring wall thickness and the clearance between disk margin and ring inner wall, influence the results of the containment.The numerical simulation can be adapted to the impact and containment with different materials and structures. The numerical simulation becomes a superior and effective means to deal with the impact and containment, while testing expenses is high and R&D cycle is long.