Implicit Differential Equations
Mostrando 1-12 de 15 artigos, teses e dissertações.
-
1. AN EOS-BASED NUMERICAL SIMULATION OF THERMAL RECOVERY PROCESS USING UNSTRUCTURED MESHES
Abstract In the past thirty years, the development of compositional reservoir simulators using an equation of state (EOS) has been addressed in the literature. However, the development of compositional thermal simulators in conjunction with the EOS formulation, in particular, has not been addressed extensively. In this work, a fully implicit, thermal, compos
Braz. J. Chem. Eng.. Publicado em: 2015-03
-
2. Comparison of an impec and a semi-implicit formulation for compositional reservoir simulation
In compositional reservoir simulation, a set of non-linear partial differential equations must be solved. In this work, two numerical formulations are compared. The first formulation is based on an implicit pressure and explicit composition (IMPEC) procedure, and the second formulation uses an implicit pressure and implicit saturation (IMPSAT). The main goal
Braz. J. Chem. Eng.. Publicado em: 2014-12
-
3. Um estudo comparativo de mÃtodos de simulaÃÃo de tecidos virtuais atravÃs de sistemas de partÃculas / A comparative study of methods for simulation of virtual fabrics with particulate systems
Physically based cloth animation has gained much attention from researchers in the last two decades, due to the challenges of realism and performance placed by the film and game industries, as well as by the applications of virtual reality and e-commerce. Consequently, there have been overwhelming achievements in this area, and several approaches have been p
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/03/2012
-
4. Numerical solution of coupled mass and energy balances during osmotic microwave dehydration
The mass and energy transfer during osmotic microwave drying (OD-MWD) process was studied theoretically by modeling and numerical simulation. With the aim to describe the transport phenomena that occurs during the combined dehydration process, the mass and energy microscopic balances were solved. An osmotic-diffusional model was used for osmotic dehydration
Comput. Appl. Math.. Publicado em: 2012
-
5. Integração numérica de sistemas não lineares semi-implícitos via teoria de controle geométrico / Numerical integration of non-linear semi-implicit square systems via geometric control theory.
This work improves a method to approximate solutions for a class of differential algebraic equations (DAEs), known as systems semi-implicit square. The method, called here MII, is based on geometric theory of decoupling for nonlinear systems combined with efficient techniques numerical analysis. It uses an algorithum that mixes symbolic and numerical calcula
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 04/11/2011
-
6. Nonlinear turbulent transonic flow phenomena influence on aeroelastic stability analysis.
The present work is aimed at studying the influence of viscous effects in transonic aeroelastic analyses. To achieve this goal, a two-dimensional and viscous aeroelastic computational solver, for CAE analysis, is developed, which uses unstructured computational meshes and which is able to capture the main aeroelastic phenomena relevant in the transonic regim
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/12/2010
-
7. Nonlinear turbulent transonic flow phenomena influence on aeroelastic stability analysis.
The present work is aimed at studying the influence of viscous effects in transonic aeroelastic analyses. To achieve this goal, a two-dimensional and viscous aeroelastic computational solver, for CAE analysis, is developed, which uses unstructured computational meshes and which is able to capture the main aeroelastic phenomena relevant in the transonic regim
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/12/2010
-
8. Simulação numérica do escoamento bifásico em meios porosos heterogêneos empregando uma formulação semi-implícita, imitadores de fluxo e o método dos volumes finitos / Numerical simulation of two-phase flow in heterogeneous porous media applying a semi-implicit formulation, flux limiter and finite volume method
A new numerical method is proposed for the solution of two-phase flow problem in petroleum reservoirs. The two-phase (water and oil) flow problem is governed by a pressure-velocity equation coupled to a saturation equation. For computational eficiency an operator spliting technique is used; distinct time steps can be used for the computation of transport and
Publicado em: 2009
-
9. Desidratação osmotica e secagem convectiva de maçã : transferencia de massa e alterações de estrutura celular / Osmotic dehydrations and convective drying apple; : mass transfer and cellular structure changes
In this study it was investigated the osmotic dehydration of apples (Fuji variety) followed or not by convective drying with hot air. Concentration profiles were determined for water and solute(s) in samples of apples cut in half and osmotically dehydrated in binary aqueous solutions (30% and 50% sucrose, w/w) and ternary solution (50% sucrose and 10% sodium
Publicado em: 2009
-
10. Index of binary differential equations / Índice de equações diferenciais binárias
In this work we study binary differential equations in a neighborhood of an isolated singular point. Following the geometric approach of Bruce and Tari in their work on multiplicity of a binary differential equation, we introduce a new definition of index for this class of equations, which coincides with the classical definition by Hopf for positive binary d
Publicado em: 2006
-
11. Decoupling geometry and numerical integration of differential equations implicit nonlinear systems. / Geometria do desacoplamento e integração numérica de equações diferenciais não lineares implícitas.
Classical methods for numerical integration of diferential algebraic equations (DAEs) can be formal in the literature. In this work, using a diferential geometric approach, a numerical method of integration of DAEs is established. This method is inspired in the decoupling theory of nonlinear explicit systems, when one considers that the outputs are algebraic
Publicado em: 2006
-
12. STATIC AND DYNAMIC INSTABILITY OF PLANE FRAMES WITH SEMI-RIGID CONNECTIONS / INSTABILIDADE ESTÁTICA E DINÂMICA DE PÓRTICOS PLANOS COM LIGAÇÕES SEMI-RÍGIDAS
The main objective of this thesis is to develop a numerical methodology for the nonlinear static and dynamics analysis of plane frames with semi-rigid connections. Initially, the formulations of the adopted finite elements are presented and implemented together with numerical methodologies for the solution of the non-linear equilibrium equations. Then, some
Publicado em: 2004