Sharif Digital Repository

In this paper, new assumptions are made to determine the energy dissipation capacity of the basic folding mechanism. The basic folding mechanism, introduced by Wierzbicki and Abramowiciz is an intelligent mathematical imitation of the real crumpling process for simple structural sections. A contribution factor for some part of energy absorption and the new concept of varying rolling radios, based on minimizing instantaneously applied load, are utilized to enrich the old analytical solution. A set of finite element analyses on the axial collapse of square boxcolumns with various cross sections and width to thickness ratios, has been performed to verify the proposed analytical solution vs. the... 

Anisotropy and heterogeneity in reservoir properties introduce challenges during the development of hydrocarbon reservoirs in naturally fractured reservoirs. In reservoir simulations, grid-block properties are frequently assigned to obtain reasonable history matches. Even then, accuracy with regard to some aspects of the performance such as water or gas cuts, breakthrough times, and sweep efficiencies may be inadequate. In some cases, this could be caused by the presence of substantial flow through natural fractures. In this work the fracture characterization and modeling was performed in a highly fractured carbonate reservoir in SW Iran. It was observed that reservoir simulation based on...