Large Eddy Simulation of Compressible Turbulent Channel and Annular Pipe Flows with System and Wall Rotations

Large Eddy Simulation of Compressible Turbulent Channel and Annular Pipe Flows with System and Wall Rotations
Author: Joon Sang Lee
Publisher:
Total Pages: 262
Release: 2004
Genre:
ISBN:

The compressible filtered Navier-Stokes equations were solved using a second order accurate finite volume method with low Mach number preconditioning. A dynamic subgrid-scale stress model accounted for the subgrid-scale turbulence. The study focused on the effects of buoyancy and rotation on the structure of turbulence and transport processes including heat transfer. Several different physical arrangements were studied as outlined below. The effects of buoyancy were first studied in a vertical channel using large eddy simulation (LES). The walls were maintained at constant temperatures, one heated and the other cooled. Results showed that aiding and opposing buoyancy forces emerge near the heated and cooled walls, respectively. In the aiding flow, the turbulent intensities and heat transfer were suppressed at large values of Grashof number. In the opposing flow, however, turbulence was enhanced with increased velocity fluctuations. Another buoyancy study considered turbulent flow in a vertically oriented annulus. Isoflux wall boundary conditions with low and high heating were imposed on the inner wall while the outer wall was adiabatic. The results showed that the strong heating and buoyancy force caused distortions of the flow structure resulting in reduction of turbulent intensities, shear stress, and turbulent heat flux, particularly near the heated wall. Flow in an annular pipe with and without an outer wall rotation about its axis was first investigated at moderate Reynolds numbers. When the outer pipe wall was rotated, a significant reduction of turbulent kinetic energy was realized near the rotating wall. Secondly, a large eddy simulation has been performed to investigate the effect of swirl on the heat and momentum transfer in an annular pipe flow with a rotating inner wall. The simulations indicated that the Nusselt number and the wall friction coefficient increased with increasing rotation speed of the wall. It was also observed that the axial velocity profile became flattened and turbulent intensities were enhanced due to swirl. As a part of the study of rotation effects, a large eddy simulation of a rotating ribbed channel flow with the heat transfer was investigated. The rotation axis was parallel to the spanwise direction of the parallel plate channel. Uniform heat flux was applied to the channel for two rates of rotation. The results showed that near the stable (leading) side, the turbulent intensities and heat transfer were suppressed, but turbulence was enhanced with increasing shear stress and turbulent kinetic energy near the unstable (trailing) side.

Large Eddy Simulation for Compressible Flows

Large Eddy Simulation for Compressible Flows
Author: Eric Garnier
Publisher: Springer Science & Business Media
Total Pages: 280
Release: 2009-08-11
Genre: Science
ISBN: 9048128196

This book addresses both the fundamentals and the practical industrial applications of Large Eddy Simulation (LES) in order to bridge the gap between LES research and the growing need to use it in engineering modeling.

Large Eddy Simulation of Compressible Turbulent Pipe Flow with Heat Transfer

Large Eddy Simulation of Compressible Turbulent Pipe Flow with Heat Transfer
Author: Xiaofeng Xu
Publisher:
Total Pages: 306
Release: 2003
Genre:
ISBN:

A compressible finite volume formulation for large eddy simulation (LES) of turbulent channel flows was extended to solve the turbulent flows in pipes and annular passages. A general finite volume scheme was developed based on conservation equations in Cartesian coordinates with non-Cartesian control volumes. A dual-time stepping approach with time derivative preconditioning was employed and time marching was done with an implicit lower-upper-symmetric-Gauss-Seidel (LU-SGS) scheme. The small scale motions were modeled by a dynamic subgrid-scale (SGS) model. The code was developed in a multiblock framework and parallelized using the message passing interface (MPI). The finite volume LES formulation was validated by simulating the isothermal fully developed turbulent pipe and annular flows. The results were compared to experimental data and direct numerical simulation (DNS) results. The LES formulation was further validated by the simulation of turbulent pipe flows with low heat transfer and comparisons with passive scalar DNS results. Finally, buoyancy forces were added into the LES formulation to simulate mixed convection in a vertical pipe with constant high wall heat fluxes leading to significant property variations. Step-periodic boundary conditions were studied and implemented. The results were validated by comparing with experimental results. Heating effects and flow laminarization were studied. Excellent agreement with DNS and experimental results were obtained for isothermal turbulent pipe and annular flows. The mean temperature profile for the turbulent pipe flow with low heat transfer matched very well with the DNS passive scalar results. Good matches to constant property correlations were also achieved for friction coefficients and Nusselt numbers. For the mixed convection in a vertical pipe, good agreement with the experimental mean streamwise velocity and temperature profiles was obtained. High heating tended to suppress the turbulent intensities and attenuate the turbulent kinetic energy. The thinner viscous layer led to a larger Nusselt numbers which indicated a higher heat transfer rate. Laminarization phenomena were observed along with large overprediction of friction coefficients and underprediction of Nusselt numbers when comparing to fully turbulent property variation correlations.

Large Eddy Simulation for Incompressible Flows

Large Eddy Simulation for Incompressible Flows
Author: P. Sagaut
Publisher: Springer Science & Business Media
Total Pages: 600
Release: 2006
Genre: Computers
ISBN: 9783540263449

First concise textbook on Large-Eddy Simulation, a very important method in scientific computing and engineering From the foreword to the third edition written by Charles Meneveau: "... this meticulously assembled and significantly enlarged description of the many aspects of LES will be a most welcome addition to the bookshelves of scientists and engineers in fluid mechanics, LES practitioners, and students of turbulence in general."

Large-Eddy Simulations of Turbulence

Large-Eddy Simulations of Turbulence
Author: M. Lesieur
Publisher: Cambridge University Press
Total Pages: 240
Release: 2005-08-22
Genre: Mathematics
ISBN: 9780521781244

Large-Eddy Simulations of Turbulence is a reference for LES, direct numerical simulation and Reynolds-averaged Navier-Stokes simulation.

Large Eddy Simulation of Wall Bounded Turbulent Flows with Heat Transfer

Large Eddy Simulation of Wall Bounded Turbulent Flows with Heat Transfer
Author: Yang Liu
Publisher:
Total Pages: 274
Release: 2002
Genre:
ISBN:

In this thesis work, large eddy simulation was used to study a variety of wall-bounded turbulent flows using a compressible finite volume formulation. Subgrid scale terms in both momentum and energy equations were modeled dynamically. Furthermore, due to the inhomogeniety of wall-bounded flows, the model was further localized to better represent the physics of the problem. The model was first applied to study the incompressible turbulent flow through a duct with square cross-section. Mean flow, law of the wall, and turbulence statistics were compared with the benchmark results of direct numerical simulation and excellent agreement was achieved. The secondary flow in the cross-section was captured. It is composed of four pairs of counter-rotating cells. The interaction between mean and secondary flow fields creates some important features and they were studied in this work. Based on incompressible duct flow, system rotation was applied to investigate the effects of rotation on the turbulent flow field. The system rotation was found to reduce turbulence level on the leading side, while increase turbulence level on the trailing side. Because of the rotation, the secondary flow field in non-rotating duct was found to be diminished at weaker rotation and even eliminated at stronger rotation. Instead, a pair of counter rotating cells called Taylor-Görtler vortices, as well as the Taylor-Proudman regime, was found to exist in the cross-section, which is consistent with the results of the literature. Large eddy simulation was also applied to investigate the effects of ribs and system rotation on heat transfer in a channel. It was found that a rib creates recirculation zones near the rib. The turbulence level is at its maximum near the ribs. The existence of ribs enhances heat transfer significantly over the plane channel, as well as creates low-heat-transfer-coefficient region in the recirculation zones. This means a balance is needed between global enhancement and local suppression. With system rotation, heat transfer is greatly enhanced on the trailing side, while significantly reduced on the leading side.

Direct and Large-Eddy Simulation XI

Direct and Large-Eddy Simulation XI
Author: Maria Vittoria Salvetti
Publisher: Springer
Total Pages: 608
Release: 2019-02-02
Genre: Technology & Engineering
ISBN: 3030049159

This book gathers the proceedings of the 11th workshop on Direct and Large Eddy Simulation (DLES), which was held in Pisa, Italy in May 2017. The event focused on modern techniques for simulating turbulent flows based on the partial or full resolution of the instantaneous turbulent flow structures, as Direct Numerical Simulation (DNS), Large-Eddy Simulation (LES) or hybrid models based on a combination of LES and RANS approaches. In light of the growing capacities of modern computers, these approaches have been gaining more and more interest over the years and will undoubtedly be developed and applied further. The workshop offered a unique opportunity to establish a state-of-the-art of DNS, LES and related techniques for the computation and modeling of turbulent and transitional flows and to discuss about recent advances and applications. This volume contains most of the contributed papers, which were submitted and further reviewed for publication. They cover advances in computational techniques, SGS modeling, boundary conditions, post-processing and data analysis, and applications in several fields, namely multiphase and reactive flows, convection and heat transfer, compressible flows, aerodynamics of airfoils and wings, bluff-body and separated flows, internal flows and wall turbulence and other complex flows.

Direct and Large Eddy Simulation XIII

Direct and Large Eddy Simulation XIII
Author: Cristian Marchioli
Publisher: Springer Nature
Total Pages: 389
Release: 2023-11-15
Genre: Technology & Engineering
ISBN: 3031470281

This book covers the diverse and cutting-edge research presented at the 13th ERCOFTAC Workshop on Direct and Large Eddy Simulation. The first section of the book focuses on Aerodynamics/Aeroacoustics, comprising eight papers that delve into the intricate relationship between fluid flow and aerodynamic performance. The second section explores the dynamics of Bluff/Moving Bodies through four insightful papers. Bubbly Flows, the subject of the third section, is examined through four papers. Moving on, the fourth section is dedicated to Combustion and Reactive Flows, presenting two papers that focus on the complex dynamics of combustion processes and the interactions between fluids and reactive species. Convection and Heat/Mass Transfer are the central themes of the fifth section, which includes three papers. These contributions explore the fundamental aspects of heat and mass transfer in fluid flows, addressing topics such as convective heat transfer, natural convection, and mass transport phenomena. The sixth section covers Data Assimilation and Uncertainty Quantification, featuring two papers that highlight the importance of incorporating data into fluid dynamic models and quantifying uncertainties associated with these models. The subsequent sections encompass a wide range of topics, including Environmental and Industrial Applications, Flow Separation, LES Fundamentals and Modelling, Multiphase Flows, and Numerics and Methodology. These sections collectively present a total of 23 papers that explore different facets of fluid dynamics, contributing to the advancement of the field and its practical applications.

Direct and Large-Eddy Simulation II

Direct and Large-Eddy Simulation II
Author: Jean-Pierre Chollet
Publisher: Springer Science & Business Media
Total Pages: 436
Release: 2012-12-06
Genre: Science
ISBN: 9401156247

Progress in the numerical simulation of turbulence has been rapid in the 1990s. New techniques both for the numerical approximation of the Navier-Stokes equations and for the subgrid-scale models used in large-eddy simulation have emerged and are being widely applied for both fundamental and applied engineering studies, along with novel ideas for the performance and use of simulation for compressible, chemically reacting and transitional flows. This collection of papers from the second ERCOFTAC Workshop on Direct and Large-Eddy Simulation, held in Grenoble in September 1996, presents the key research being undertaken in Europe and Japan on these topics. Describing in detail the ambitious use of DNS for fundamental studies and of LES for complex flows of potential and actual engineering importance, this volume will be of interest to all researchers active in the area.

Direct and Large-Eddy Simulation VIII

Direct and Large-Eddy Simulation VIII
Author: Hans Kuerten
Publisher: Springer Science & Business Media
Total Pages: 460
Release: 2011-10-05
Genre: Computers
ISBN: 9400724829

This volume continues previous DLES proceedings books, presenting modern developments in turbulent flow research. It is comprehensive in its coverage of numerical and modeling techniques for fluid mechanics. After Surrey in 1994, Grenoble in 1996, Cambridge in 1999, Enschede in 2001, Munich in 2003, Poitiers in 2005, and Trieste in 2009, the 8th workshop, DLES8, was held in Eindhoven, The Netherlands, again under the auspices of ERCOFTAC. Following the spirit of the series, the goal of this workshop is to establish a state-of-the-art of DNS and LES techniques for the computation and modeling of transitional/turbulent flows covering a broad scope of topics such as aerodynamics, acoustics, combustion, multiphase flows, environment, geophysics and bio-medical applications. This gathering of specialists in the field was a unique opportunity for discussions about the more recent advances in the prediction, understanding and control of turbulent flows in academic or industrial situations.