Critical assessment of the operator-splitting technique in solving the advection-dispersion-reaction equation: 2. Monod kinetics and coupled transport

AbstractThe paper deals with the nonlinear inverse source problem of identifying an unknown time-dependent point source occurring in a two-dimensional evolution advection-dispersion-reaction equation with spatially varying velocity field and dispersion tensor. The

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Accuracy of the Operator Splitting Technique for Two-Phase Flow With Stiff Source Terms

Volume 1: Fora, Parts A and B ◽

10.1115/fedsm2002-31349 ◽

2002 ◽

Cited By ~ 4

Author(s):

Iztok Tiselj ◽

Andrej Horvat

Keyword(s):

Two Phase Flow ◽

Fluid Model ◽

Operator Splitting ◽

Splitting Method ◽

Water Hammer ◽

Phase Flow ◽

Hydraulic Systems ◽

Source Terms ◽

Two Phase ◽

Splitting Technique

Code for analysis of the water hammer in thermal-hydraulic systems is being developed within the WAHALoads project founded by the European Commission [1]. Code will be specialized for the simulations of the two-phase water hammer phenomena with the two-fluid model of two-phase flow. The proposed numerical scheme is a two-step second-order accurate scheme with operator splitting; i.e. convection and sources are treated separately. Operator splitting technique is a very simple and “easy-to-use” tool, however, when the source terms are stiff, operator splitting method becomes a source of a specific non-accuracy, which behaves as a numerical diffusion. This type of error is analyzed in the present paper.

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Structural Integrity of Flexible Piping Systems Conveying Liquids

Journal of Pressure Vessel Technology ◽

10.1115/1.2217966 ◽

2005 ◽

Vol 128 (3) ◽

pp. 341-347 ◽

Cited By ~ 3

Author(s):

Felipe BastosFreitas Rachid

Keyword(s):

Structural Integrity ◽

Mathematical Problem ◽

Nonlinear Partial Differential Equations ◽

Operator Splitting ◽

Piping System ◽

Damage Growth ◽

Splitting Technique ◽

Structure Interaction ◽

Piping Systems ◽

Fast Transients

This work presents a structural integrity model for piping systems conveying liquids which takes the axial fluid-structure interaction into account. The model is used to numerically investigate the influence of pipe motion on the degradation of the piping when fast transients are generated by valve slam. The resulting mathematical problem is formed by a system of nonlinear partial differential equations which is solved by means of an operator splitting technique, combined with Glimm’s method. Numerical results obtained for an articulated piping system indicate that high piping flexibility may induce a substantial increase in damage growth along the pipes.

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The Influence of Pipe Motion on the Integrity of Liquid-Filled Pipes Subjected to Pressure Transients

Volume 4: Fluid Structure Interaction ◽

10.1115/pvp2005-71115 ◽

2005 ◽

Cited By ~ 1

Author(s):

Felipe Bastos de Freitas Rachid

Keyword(s):

Partial Differential Equations ◽

Differential Equations ◽

Mathematical Problem ◽

Operator Splitting ◽

Damage Growth ◽

Splitting Technique ◽

Structure Interaction ◽

Linear Partial Differential Equations ◽

Piping Systems ◽

Fast Transients

This work presents a structural itegrity model for piping systems conveying liquids which takes the axial fluid-structure interaction into account. The model is used to numerically investigate the influence of pipe motion on the degradation of the piping when fast transients are generated by valve slam. The resulting mathematical problem is formed by a system of non-linear partial differential equations which is solved by means of an operator splitting technique, combined with a Glimm’s method. Numerical results obtained indicate that high piping flexibility may introduce a substantial increase in damage growth along the pipes.

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Forced Convection Flow Through an Unsaturated Wellbore

Heat Transfer, Volume 1 ◽

10.1115/imece2003-41128 ◽

2003 ◽

Author(s):

Maria Laura Martins-Costa ◽

Roge´rio M. Saldanha da Gama

Keyword(s):

Nonlinear Partial Differential Equations ◽

Operator Splitting ◽

Mixture Theory ◽

Porous Matrix ◽

Convection Flow ◽

Theory Approach ◽

Splitting Technique ◽

Nonlinear Hyperbolic System ◽

Implicit Finite Difference Scheme ◽

Flow Through

This work studies the dynamics of the filling up of a rigid cylindrical shell porous matrix by a Newtonian fluid and the heat transfer associated phenomenon. A mixture theory approach is employed to obtain a preliminary local model for nonisothermal flows through a wellbore. The mixture consists of three overlapping continuous constituents: a solid (porous medium), a liquid and an inert gas included to account for the compressibility of the mixture as a whole. Assuming the convection flow on radial direction only, a set of four nonlinear partial differential equations describes the problem. Its hydrodynamic part — a nonlinear hyperbolic system — is approximated by means of a Glimm’s scheme, combined with an operator splitting technique, while an implicit finite difference scheme is used to simulate the thermal part.

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