Poster Presentations

Design of a Petal Tool for Polishing Optical Surfaces Using Linear Programming

Dynamics of a Compressible Viscous Fluid in a Finite Pipe with Peristaltic Transport
EOR/IOR Methods Assessment Through Oil Residual Saturation Estimated by Kernel Ridge Regression

An Evaluation of a Bounded High Order Upwind Scheme
for 3D Incompressible Free Surface Flow Computations

Valdemir G. Ferreira

Fernando A. Kurokawa

Abstract: The scope of this work is to give an evaluation of the bounded high order upwind adaptative QUICKEST scheme to solve 3D incompressible free surface flows. By using the primitive variables of the velocity and pressure, the full Navier-Stokes equations are solved by an explicit finite difference projection method. The procedure is an adaptation of the GENSMAC methodology for calculating free surface flows at high Reynolds numbers. The calculations are performed by using the Freeflow simulation system. In order to demonstrate the capabilities of the numerical method, two cases are presented. These are the broken dam flow and an impinging jet onto a flat rigid surface.

Design of a Petal Tool for Polishing Optical Surfaces Using Linear Programming

Agustín Santiago Alvarado

Cuauhtémoc H. Castañeda Roldán

Jorge González García

Universidad Tecnológica de la Mixteca
Huajuapan de León, Oaxaca, México

Abstract: This study raises and solves the problem of determining the optimal dwell-times of a set of annular polishing tools on a piece of glass to generate an optical surface with the minimum possible deviation with respect to the required one. This problem is modeled as a linear program and it is solved using MATLAB. Using the times obtained, we designed incomplete annular tools with which to form a petal tool. When it spins and oscilates in contact with the glass it produces the desired wear.

Dynamics of a Compressible Viscous Fluid in a Finite Pipe with Peristaltic Transport

Yoisell Rodríguez Núñez

Mariano Rodríguez Ricard

Department of Mathematics
University of Informatics Science Car.
Havana, Cuba

Abstract: The Antanovskii-Ramkissoon model on fluids dynamics describes particularities of the sanguine flow on an artery segment. This model considers a non linear parabolic equation for the pressure of the blood that is deduced from the mass conservation law in combination with the lubrication theory. In this work, we consider a traveling wave solution that for its nature turns out to be interesting. For it, we rely on elements of porous medium flow theory as well as in the use of perturbation techniques. We also analyze the peristalsis effects in the solutions. The numerical and analytical results contribute to a better understanding of the model. Key words: Traveling wave, perturbations, peristaltic transport.

EOR/IOR Methods Assessment Through Oil Residual Saturation Estimated by Kernel Ridge Regression

Johnny Valbuena

Ana Barrios

José Alí Moreno

PDVSA Intevep S.A.
Caracas, Venezuela

Abstract: Kernel Ridge Regression (KRR) is applied to estimate oil residual saturation using a data base of oil fields. This parameter allows to evaluate the amount of retrievable crude by Enhanced Oil Recovery (EOR) and Improved Oil Recovery (IOR) methods. The recovery methods are grouped in gas, chemical and thermal methods, which are used to supply additional energy to the reservoirs through fluid injections in order to extract more crude. The application of these methods depend on reservoir properties from rock (type of formation, porosity and permeability) and fluid (oil viscosity, oil density, oil temperature, oil initial and residual saturation). A data base containing samples of these properties and covering 591 fields is considered. It is divided in two sets for generation and validation of the models. For each group, a model to calculate the saturation based on reservoir information by means of KRR is developed. The models are evaluated at the reservoir data. The results show a right assessing of the methods due to good accuracy between the estimated and target oil residual saturation.

New Formulations of the Discontinuous Galerkin Method

Sonia M. Gomes

Philippe R. B. Devloo

Tiago L. Duarte Forti

Erick S. R. Santos

Campinas SP, Brasil

Abstract: We present results of recent new formulations of the discontinuous Galerkin method for two classes of problems. Firtly, for inviscid simulations, we consider a fully implicit scheme, which is stabilized by adding diffusive terms local to each element. For typical test problems, we present simulation results for the system of Euler equations comparing the performance of four different types of diffusive terms, using interpolation orders up to p=6. Secondly, for solutions of convection-diffusion problems showing localized high-gradient regions, we propose a hybrid formulation. It combines in the same formulation the usual continuous finite element method, where the solution is smooth, with the discontinuous Galerkin method close to regions of strong variations. The result is a scheme combining the advantages of both methods.

Polarization Force Fields for Peptides in ECEPP2 and MM2

Francisco Torrens

Gloria Castellano

Universitat de Valencia-ICMol
Edifici d'Instituts de Paterna, Valencia, Spain

Abstract: The empirical conformational energy program for peptides (ECEPP2) and molecular mechanics (MM2) have been used for the simulation of the For-Gly-NH_2 backbone. Two different methods for the calculation of the polarization energy term are proposed: the polarization procedure by non-interacting induced dipoles (NID), which assumes scalar isotropic point polarizabilities and the polarization scheme by interacting induced dipoles (ID), which calculates tensor effective anisotropic point polarizabilities (method of Applequist). A comparative study of ECEPP2 and MM2+polarization is presented. Molecular mechanics results are discussed, including the total energy differences, partitional analyses of the total steric energies and torsion dihedral angles. The GAMMA global and the ALPHA, BETA and DELTA local minima are stabilized by intramolecular hydrogen bonds. Although ECEPP2-based calculations rather under or over-estimate the relative energy of some local minima, the ID polarization energy term represents a significant correction to the total relative energy. We thank Project Universitat de ValènciaMediscovery.

Solution of an Inverse Problem in Radiative Transfer Using Convex Functions Related to the Entropy of Shannon, Renyi, Varma, Havrad- Charvat, Sharma Taneja and Burn

Mariella Janette Berrocal Tito

Raul Felix Carita Montero

Nilson Costa Roberty

Jorge Passamani Zubelli

Institute of Pure and Applied Mathematics (IMPA)
BrazilFederal University of Rio de Janeiro (UFRJ) RJ, Brazil

Abstract: In this work, the absorption coefficient estimation in one-dimensional media is treated as an optimization problem; that is minimizing the Bregman distance constrain to error function. Bregman distances were built with families of strictly convex functions related to the entropy of Shannon (1948), Rényi (1961), Varma (1966), Havrda - Charvát (1967), Sharma-Taneja (1975), and Burn (Taneja, 2001; Esteban & Morales, 1995).The error function is defined by the difference between the measure detector and calculated measure by the direct problem. The direct problem was solved with finite elements, finite differences and discrete ordinates methods. With the objective of identifying the function that offers the best results, a comparison among results obtained with different functions was made, considering the percentage error.

TANEJA, I. J., 2001, "Generalized Information Measure and their Application". Book, ESTEBAN, D., MORALES, D., 1995, "A Summary on Entropy Statistics". Kybernetika. v. 31, N.4, pp. 337-346.