00000nam 2200000za 4500 9.821403 CaOODSP 20240219183450 cr ||||||||||| 160720s2011 onc|||||o f000 0 eng d CaOODSP eng eng fre n-cn--- D68-6/281-2011E-PDF MacKay, John R. Verification of numerical models for pressure hull collapse predictions [electronic resource] / by John R. MacKay. [Ottawa] : Defence Research and Development Canada, c2011. viii, 28 p. : tables, figures. Technical Memorandum ; 2011-281 "November 2011." Includes bibliographical references. The verification aspects of a verification and validation (V&V) study for the numerical modeling of the collapse of pressure hulls are described. A series of finite element (FE) analyses were performed using ANSYS in order to verify that the numerical methodology was correctly implemented in the software (code verification) and that spatial and temporal refinement of validation FE models of test specimens were adequate (calculation verification). FE predictions of elastic and inelastic buckling pressures for 140 cylinders and ring-frames under external pressure were found to be within 8%, on average, of the benchmark analytical or numerical solutions. The FE error was attributed to unavoidable differences between the numerical and benchmark models, rather than problems with the FE software, so that code verification was considered to have been achieved. With calculation verification, the nonlinear FE solution was found to be most sensitive to the spatial refinement associated with the mesh density. Load increment size was found to affect the collapse prediction to a lesser extent, and the tolerance used to define convergence of the incremental solution did not affect the collapse prediction at all when a refined mesh and load increment were used. gccst Technical reports Pressure hull Buckling Collapse Defence R&D Canada. Technical memorandum (Defence R&D Canada) 2011-281 (CaOODSP)9.820564 PDF 4.01 MB https://publications.gc.ca/collections/collection_2016/rddc-drdc/D68-6-281-2011-eng.pdf