Finite element formulations dealing with geometric and material non-linearities have been well developed and a significant amount of work has been accomplished for the numerical simulation of metal forming processes. Nevertheless, standard finite element approaches can be sometimes ineffective in handling bulk material deformation owing to severe mesh distortion or mesh entanglement. In the past, some finite element methods such as the Arbitrary Lagrangian Eulerian (ALE) method have been introduced to allow continuous remeshing during computation. Though rather effective in handling large deformation and keeping track of moving boundaries, these methods required extensive computational effort. In this thesis an attempt is made to address the aforementioned problems by using particle based Lagrangian techniques in the numerical simulation of large deformation metal forming processes. For this purpose a particle method called Corrected Smooth Particle Hydrodynamics (CSPH) is considered in the present work. CSPH method is developed from Smooth Particle Hydrodynamics (SPH) techniques which originated twenty years ago. Like most of the particle methods the CSPH also requires no explicit mesh for the computation and therefore avoids mesh direction difficulties in large deformation analysis. In addition, CSPH can achieve similar order of accuracy as any other modern mesh-less methods while retaining the simplicity of the original SPH technique. The simplicity and robustness of SPH method are demonstrated in the first few chapters of this thesis. As a first step of the present research, the SPH method is studied for evaluating its consistency, accuracy and other characteristics. As a consequence of these analyses various correction procedures are introduced in the original SPH method to enhance its performance. The resulting method is referred to here as the Corrected SPH technique. The CSPH is then used to formulate the viscoplastic forming problems with the aid of flow formulation technique.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:637828 |
| Date | January 1999 |
| Creators | Kulasegaram, S. |
| Publisher | Swansea University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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