Author:
Publisher:
ISBN:
Category :
Languages : pt-BR
Pages :
Book Description
A superposição de um escoamento circular de Couette e um fluxo com gradiente de pressão axial, através de um espaço anular ocorre em muitas aplicações práticas, tais como: reatores químicos catalíticos, filtros, extratores líquido-líquido, mancais e o fluxo de retorno de lamas de perfuração entre a coluna de perfuração rotatória e a formação rochosa na perfuração de poços produtores de petróleo e gás. As linhas de corrente curvadas do fluxo circular de Couette podem causar uma instabilidade centrífuga que produz vórtices toroidais, conhecidos como vórtices de Taylor. A presença destes vórtices muda as características hidrodinâmicas e a transferência de calor no processo. Em conseqüência, é muito importante ser capaz de prever o aparecimento da instabilidade. A maioria das análises numéricas e experimentais disponíveis na literatura são para fluidos Newtonianos e viscoelásticos (soluções polimericas). Neste trabalho, o efeito das propriedades viscoplásticas de suspensões de altas concentrações neste tipo de escoamento e nas condições críticas para o aparecimento de vórtices são determinadas teoricamente através da solução das equações de conservação. As equações diferenciais foram integradas pelo método de elementos finitos-Galerkin e o sistema de equações algébricas não lineares resultante foi resolvido pelo método de Newton.
Taylor-couette instability in viscoplastic fluid flow
Author:
Publisher:
ISBN:
Category :
Languages : pt-BR
Pages :
Book Description
A superposição de um escoamento circular de Couette e um fluxo com gradiente de pressão axial, através de um espaço anular ocorre em muitas aplicações práticas, tais como: reatores químicos catalíticos, filtros, extratores líquido-líquido, mancais e o fluxo de retorno de lamas de perfuração entre a coluna de perfuração rotatória e a formação rochosa na perfuração de poços produtores de petróleo e gás. As linhas de corrente curvadas do fluxo circular de Couette podem causar uma instabilidade centrífuga que produz vórtices toroidais, conhecidos como vórtices de Taylor. A presença destes vórtices muda as características hidrodinâmicas e a transferência de calor no processo. Em conseqüência, é muito importante ser capaz de prever o aparecimento da instabilidade. A maioria das análises numéricas e experimentais disponíveis na literatura são para fluidos Newtonianos e viscoelásticos (soluções polimericas). Neste trabalho, o efeito das propriedades viscoplásticas de suspensões de altas concentrações neste tipo de escoamento e nas condições críticas para o aparecimento de vórtices são determinadas teoricamente através da solução das equações de conservação. As equações diferenciais foram integradas pelo método de elementos finitos-Galerkin e o sistema de equações algébricas não lineares resultante foi resolvido pelo método de Newton.
Publisher:
ISBN:
Category :
Languages : pt-BR
Pages :
Book Description
A superposição de um escoamento circular de Couette e um fluxo com gradiente de pressão axial, através de um espaço anular ocorre em muitas aplicações práticas, tais como: reatores químicos catalíticos, filtros, extratores líquido-líquido, mancais e o fluxo de retorno de lamas de perfuração entre a coluna de perfuração rotatória e a formação rochosa na perfuração de poços produtores de petróleo e gás. As linhas de corrente curvadas do fluxo circular de Couette podem causar uma instabilidade centrífuga que produz vórtices toroidais, conhecidos como vórtices de Taylor. A presença destes vórtices muda as características hidrodinâmicas e a transferência de calor no processo. Em conseqüência, é muito importante ser capaz de prever o aparecimento da instabilidade. A maioria das análises numéricas e experimentais disponíveis na literatura são para fluidos Newtonianos e viscoelásticos (soluções polimericas). Neste trabalho, o efeito das propriedades viscoplásticas de suspensões de altas concentrações neste tipo de escoamento e nas condições críticas para o aparecimento de vórtices são determinadas teoricamente através da solução das equações de conservação. As equações diferenciais foram integradas pelo método de elementos finitos-Galerkin e o sistema de equações algébricas não lineares resultante foi resolvido pelo método de Newton.
A Theoretical and Experimental Investigation of Viscoelastic Instabilities in Taylor-Dean Flows
Author: Yong Lak Joo
Publisher:
ISBN:
Category :
Languages : en
Pages : 432
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 432
Book Description
Viscoelastic Flow Instabilities
Author: Marios Avgousti
Publisher:
ISBN:
Category :
Languages : en
Pages : 580
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 580
Book Description
A STUDY OF THE TAYLOR-COUETTE STABILITY OF VISCOELASTIC FLUIDS.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 185
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 185
Book Description
Ordered and Turbulent Patterns in Taylor-Couette Flow
Author: C. David Andereck
Publisher: Springer Science & Business Media
ISBN: 1461534380
Category : Science
Languages : en
Pages : 351
Book Description
Seldom does a physical system, particularly one as apparently simple as the flow of a Newtonian fluid between concentric rotating cylinders, retain the interest of scientists, applied mathematicians and engineers for very long. Yet, as this volume goes to press it has been nearly 70 years since G. I. Taylor's outstanding experimental and theoretical study of the linear stability of this flow was published, and a century since the first experiments were performed on rotating cylinder viscometers. Since then, the study of this system has progressed enormously, but new features of the flow patterns are still being uncovered. Interesting variations on the basic system abound. Connections with open flows are being made. More complex fluids are used in some experiments. The vigor of the research going on in this particular example of nonequilibrium systems was very apparent at the NATO Advanced Research Workshop on "Ordered and Turbulent Patterns in Taylor Couette Flow," held in Columbus, Ohio, USA May 22-24, 1991. A primary goal of this ARW was to bring together those interested in pattern formation in the classic Taylor Couette problem with those looking at variations on the basic system and with those interested in related systems, in order to better define the interesting areas for the future, the open questions, and the features common (and not common) to closed and open systems. This volume contains many of the contributions presented during the workshop.
Publisher: Springer Science & Business Media
ISBN: 1461534380
Category : Science
Languages : en
Pages : 351
Book Description
Seldom does a physical system, particularly one as apparently simple as the flow of a Newtonian fluid between concentric rotating cylinders, retain the interest of scientists, applied mathematicians and engineers for very long. Yet, as this volume goes to press it has been nearly 70 years since G. I. Taylor's outstanding experimental and theoretical study of the linear stability of this flow was published, and a century since the first experiments were performed on rotating cylinder viscometers. Since then, the study of this system has progressed enormously, but new features of the flow patterns are still being uncovered. Interesting variations on the basic system abound. Connections with open flows are being made. More complex fluids are used in some experiments. The vigor of the research going on in this particular example of nonequilibrium systems was very apparent at the NATO Advanced Research Workshop on "Ordered and Turbulent Patterns in Taylor Couette Flow," held in Columbus, Ohio, USA May 22-24, 1991. A primary goal of this ARW was to bring together those interested in pattern formation in the classic Taylor Couette problem with those looking at variations on the basic system and with those interested in related systems, in order to better define the interesting areas for the future, the open questions, and the features common (and not common) to closed and open systems. This volume contains many of the contributions presented during the workshop.
The Couette-Taylor Problem
Author: Pascal Chossat
Publisher:
ISBN: 9783540941545
Category : Fluid dynamics
Languages : en
Pages : 233
Book Description
Publisher:
ISBN: 9783540941545
Category : Fluid dynamics
Languages : en
Pages : 233
Book Description
Vortex Dynamics
Author: İlkay Bakırtaş
Publisher: BoD – Books on Demand
ISBN: 1803550244
Category : Science
Languages : en
Pages : 184
Book Description
This book discusses vortex dynamics theory from physics, mathematics, and engineering perspectives. It includes nine chapters that cover a variety of research results related to vortex dynamics including nonlinear optics, fluid dynamics, and plasma physics.
Publisher: BoD – Books on Demand
ISBN: 1803550244
Category : Science
Languages : en
Pages : 184
Book Description
This book discusses vortex dynamics theory from physics, mathematics, and engineering perspectives. It includes nine chapters that cover a variety of research results related to vortex dynamics including nonlinear optics, fluid dynamics, and plasma physics.
Pattern Formation in Viscous Flows
Author: Rita Meyer-Spasche
Publisher: Birkhäuser
ISBN: 9783034897389
Category : Science
Languages : en
Pages : 212
Book Description
The Taylor-Couette system is one of the most studied examples of fluid flow exhibiting the spontaneous formation of dynamical structures. In this book, the variety of time independent solutions with periodic spatial structure is numerically investigated by solution of the Navier-Stokes equations.
Publisher: Birkhäuser
ISBN: 9783034897389
Category : Science
Languages : en
Pages : 212
Book Description
The Taylor-Couette system is one of the most studied examples of fluid flow exhibiting the spontaneous formation of dynamical structures. In this book, the variety of time independent solutions with periodic spatial structure is numerically investigated by solution of the Navier-Stokes equations.
Nonlinear Stability Analyses of Non-Isothermal Viscoelastic Taylor-Couette Flow
Author: U. A. Al-Mubaiyedh
Publisher:
ISBN:
Category : Chemical engineering
Languages : en
Pages : 2
Book Description
Publisher:
ISBN:
Category : Chemical engineering
Languages : en
Pages : 2
Book Description
The Onset of Purely Elastic and Thermo-elastic Instabilities in the Taylor-Couette Flow
Author: MohammadReza Ghanbari
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Linear stability analysis of Taylor-Couette flow of dilute polymeric solutions has been performed by using two prototypical constitutive equations for polymeric solutions namely, the Oldroyd-B and the FENE-P models. The hydrodynamic stability characteristics of the flow in presence and absence of thermal effects and in the limit of vanishing fluid inertia have been determined using an eigenvalue analysis. Particular attention has been paid to accurate determination of the instability onset conditions as a function of fluid thermal sensitivity and gap ratio. We observe a reduction in the critical Deborah, Dec for the instability onset as the gap ratio and fluid thermal sensitivity is enhanced. In particular, under non-isothermal conditions, Dec is reduced by almost an order of magnitude for all gap ratios. Our results suggest that recent experiments leading to observations of "purely elastic turbulence" in the Taylor-Couette flow at order (1) De by Steinberg and Groisman (reference 17) were not performed under isothermal conditions. Hence, this new flow state should be labeled as "thermo-elastic turbulence".
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Linear stability analysis of Taylor-Couette flow of dilute polymeric solutions has been performed by using two prototypical constitutive equations for polymeric solutions namely, the Oldroyd-B and the FENE-P models. The hydrodynamic stability characteristics of the flow in presence and absence of thermal effects and in the limit of vanishing fluid inertia have been determined using an eigenvalue analysis. Particular attention has been paid to accurate determination of the instability onset conditions as a function of fluid thermal sensitivity and gap ratio. We observe a reduction in the critical Deborah, Dec for the instability onset as the gap ratio and fluid thermal sensitivity is enhanced. In particular, under non-isothermal conditions, Dec is reduced by almost an order of magnitude for all gap ratios. Our results suggest that recent experiments leading to observations of "purely elastic turbulence" in the Taylor-Couette flow at order (1) De by Steinberg and Groisman (reference 17) were not performed under isothermal conditions. Hence, this new flow state should be labeled as "thermo-elastic turbulence".