Deformation prediction model of thin walled spherical shells under flat headed projectile impact

DOI:	10.11809/bqzbgcxb2024.10.001
Keywords:	thin walled spherical shell; impact load; Digital Image Correlation; dimensional analysis; prediction model
Abstract:	To study the deformation characteristics of thin walled spherical shells under local impact loads, experimental research and numerical simulation analysis were conducted. Utilizing a light gas gun, projectile impact experiments were carried out, and the dynamic deformation process of the shell was captured using stereo DIC technology. The overall deformation morphology and concave deformation characteristics of the flattened spherical shell were obtained under different initial impact velocities of the projectile. Through numerical simulation methods, the influence and rules of various projectile size parameters and shell size parameters on the depth and radius of the central concave were studied. Dimensional analysis was used to identify the main dimensionless parameters affecting the dimensionless deformation characteristics. A response surface model describing the impact response of shells of different sizes and impact velocities was established, and a formula describing the relationship between global concave deformation and central concave depth, as well as concave radius, was proposed.The established model demonstrates high predictive accuracy for global indentation deformation of thin shell structures with diameter to thickness ratios ranging from 1/250 to 1/50 and dimensionless impact energies between 132 and 1190. This study provides valuable guidance for the design of impact load protection for large scale curved thin shell structures in engineering applications.
Issue:	Vol. 45 No. 10 (2024)
Published:	2024-10-31
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