Numerical Solution for Polymer Transient Flows in a Circle Bounded Composite Formation

A new numerical model for transient flows of polymer solution in a circular bounded composite formation is presented in this paper. Typical curves of the wellbore transient pressure are yielded by FEM. The effects of non-Newtonian power-law index, mobility and boundary distance have been considered. It is found that for the mobility ratio larger than 1, which is favorable for the polymer flooding, the pressure derivative curve in log-log form rises up without any hollow. On the other hand, if the pressure derivative curve has a hollow and then is raised up, we say that the polymer flooding fails. Finally, the new model has been extended to more complicated boundary case.

Edge and Size Effects in Micro Composite Structure

Because of the load transfer effect of interface layer, the stress distribution inside the composite structure of film/substrate can be very different from the Timoshenko's model. In this paper, we give the derivation and analysis of such load transfer effect of shear-lag (S-L) model. The micro-structure size (boundary conditions) effect together with interface load transfer effect becomes more and more important as the microstructure size including the three dimensions of thickness, width and length shrinks. The microstructure size is also responsible for the so-called edge-induced stress. The edge effect and difference of S-L model and Timoshenko model are also demonstrated.

Fixed Points of Closed and Compact Composite Sequences of Operators and Projectors in a Class of Banach Spaces

Some results on fixed points related to the contractive compositions of bounded operators in a class of complete metric spaces which can be also considered as Banach's spaces are discussed through the paper. The class of composite operators under study can include, in particular, sequences of projection operators under, in general, oblique projective operators. In this paper we are concerned with composite operators which include sequences of pairs of contractive operators involving, in general, oblique projection operators. The results are generalized to sequences of, in general, nonconstant bounded closed operators which can have bounded, closed, and compact limit operators, such that the relevant composite sequences are also compact operators. It is proven that in both cases, Banach contraction principle guarantees the existence of unique fixed points under contractive conditions.