AN INCREMENTAL ELASTIC-PLASTIC FINITE-ELEMENT SOLVER IN A WORKSTATIONCLUSTER ENVIRONMENT .2. PERFORMANCE OF A FIRST IMPLEMENTATION

This work illustrates results obtained by implementing in a parallel c omputer environment the A: rate formulation of the theory of plasticit y and its integration scheme as illustrated in the preceding Part I. T he Preconditioned Conjugate Gradient is used as a tool for repeatedly solving linear systems of equations. Although the investigation about the performance of the workstation cluster as a parallel virtual compu ter is still far from being completed, it is already possible to concl ude that, in such an environment, several techniques proposed for redu cing the computer time required by the iterative solver are not applic able. One purpose of the work is therefore to give guidelines in terms of expected performances of the Conjugate Gradient method when applie d to stiff problems, in which the condition number may shoot up to the billions. Even if the implemented computer code is not based on the m ost convenient rate formulation in terms of parallelizability, as show n in Part I of this work, the obtained results indicate anyway that, f or some categories of structural problems, the development of a parall el, element-by-element computer code is a promising line of work.