Abstract

One of the most important tasks in Petroleum Engineering is a reservoir characterization. A good knowledge of the properties of the reservoirs is essential for reliable production forecasts and the application of special methods of secondary recovery. A very useful tool for this purpose is the numerical simulation of oil reservoirs, which through the application of numerical methods allows for the solution of complex differential equations by nature. This paper deals with the computational modeling of foam injection in oil reservoirs using the Eclipse® software. The main objective of this research is to understand what the parameters that maximize the increase of the oil recovery factor retained in the pore space after using conventional methods are. Foam is injected from the surface into a reservoir of 8.400 feet deep containing oil viscosity which is dependent on the pressure, this oil is conducted to the surface through a production well. Both wells are completed over the entire thickness of the formation of interest. Equations that express the detailed model and the foam are discretized together with the governing equations of the fluid flow. Comparisons at different foam concentration are shown for light, intermediate and heavy oils. Results show that there is a direct correlation between the concentration of the displacing fluid foam and the oil recovery factor. Note also that a critical concentration c* foam is evidenced with direct influence on the efficiency of the process.

Abstract

This paper presents a technological application of a general methodology to analyze cable structures under moving loads, particularly on the catenary-pantograph dynamic interaction. This work firstly describes the modeling of a finite element moving mesh which integrally moves over the contact wire following the pantograph along the whole catenary, prior focusing on its comparison against the classical finite element mesh. The case study corresponds to the standard EN-50318 one, whose results fulfill the ranges proposed by this validation rule. The main advantage of the moving mesh method is presented in the falling of computational costs about 4 times lower than the classic model with similar precision.

Abstract

A numerical method is proposed for the seismic response analysis of rectangular and cylindrical tanks accounting for non-linear hydrodynamic effects. The equations of motion are mapped from the physical to the computational domain by means of a change of variable. The numerical solution is then obtained by means of finite differences. The system of second order equations obtained from the finite difference discretization are linearized using the Newton method and solved numerically by means of the biconjugate gradient method. The numerical formulation was applied to study the response of tanks subjected to ground motion records from the Mexico earthquake of 19 September 1985, obtained in Mexico City. Response results are given in terms of wave height on the liquid surface, and shear force and overturning moment at the base wall, and are compared with those obtained for the linear solution.