فهرس المقالات Boundary element method

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  1 - Fracture Parameters for Cracked Cylincal Shells
  M Kadri A Sahli S Sahli
  10.22034/jsm.2019.664221
  In this paper, 2D boundary element stress analysis is carried out to obtain the T-stress for multiple internal edge cracks in thick-walled cylinders for a wide range of cylinder radius ratios and relative crack depth. The T-stress, together with the stress intensity fac أکثر

  In this paper, 2D boundary element stress analysis is carried out to obtain the T-stress for multiple internal edge cracks in thick-walled cylinders for a wide range of cylinder radius ratios and relative crack depth. The T-stress, together with the stress intensity factor K, provides amore reliable two-parameter prediction of fracture in linear elastic fracture mechanics. T-stress weight functions are then derived from the T-stress solutions for two reference load conditions corresponding to the cases when the cracked cylinder is subject to a uniform and to a linear applied stress variation on the crack faces. The derived weight functions are then verified for several non-linear load conditions. Using the BEM results as reference T-stress solutions; the T-stress weight functions for thick-walled cylinder have also been derived. Excellent agreements between the BEM results and weight function predictions are obtained. The weight functions derived are suitable for obtaining T-stress solutions for the corresponding cracked thick-walled cylinder under any complex stress fields. Results of the study show that the two dimensional BEM analysis, together with weight function method, can be used to provide a quick and accurate estimate of T-stress for 2-D crack problems. تفاصيل المقالة
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  2 - Thermoelastic Fracture Parameters for Anisotropic Plates
  S Kebdani A Sahli S Sahli
  This paper deals with the determination of the effect of varying material properties on the value of the stress intensity factors, KI and KII, for anisotropic plates containing cracks and subjected to a temperature change. Problems involving cracks and body forces, as w أکثر

  This paper deals with the determination of the effect of varying material properties on the value of the stress intensity factors, KI and KII, for anisotropic plates containing cracks and subjected to a temperature change. Problems involving cracks and body forces, as well as thermal loads are analysed. The quadratic isoperimetric element formulation is utilized, and SIFs may be directly obtained using the ‘traction formula’ and the ‘displacement formula’. Three cracked plate geometries are considered in this study, namely: (1) a plate with an edge-crack; (2) a plate with a double edge-crack; (3) a plate with symmetric cracks emanating from a central hole. Where appropriate, finite element method (FEM) analyses are also performed in order to validate the results of the BEM analysis. The results of this study show that, for all crack geometries, the mode-I stress intensity factor, K∗I decreases as the anisotropy of the material properties is increased. Additionally, for all these cases, K∗I decreases as the angle of orientation of the material properties, , increases with respect to the horizontal axis. The results also show that BEM is an accurate and efficient method for two-dimensional thermoelastic fracture mechanics analysis of cracked anisotropic bodies. تفاصيل المقالة
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  3 - Hydrodynamic Design of Contra-Rotating Propeller for the Ships
  حسن قاسمی رویا شادمانی
  This paper describes a contra-rotating propeller (CRP) system to calculate the hydrodynamic characteristics and then design the optimum operational condition to be installed on two different large bulk carriers and VLCC. The method is based on boundary element method (B أکثر

  This paper describes a contra-rotating propeller (CRP) system to calculate the hydrodynamic characteristics and then design the optimum operational condition to be installed on two different large bulk carriers and VLCC. The method is based on boundary element method (BEM) to obtain the hydrodynamic performance of any complicated configuration such as CRP system, and then the optimum propeller data is obtained by the systematic method at the design condition. The researchers prepared a software package code, namely SPD, which has model mesh generation, solver and numerical output results. The comparison of the propulsive performance was made between the propeller alone and CRP arrangement. Major finding include optimal agreement between predictions using the numerical code and experimental data for both ships. تفاصيل المقالة