Simulation Of The Flow Over A Flat Dimpled Plate
DOWNLOAD
Download Simulation Of The Flow Over A Flat Dimpled Plate PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Simulation Of The Flow Over A Flat Dimpled Plate book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Simulation Of The Flow Over A Flat Dimpled Plate
DOWNLOAD
Author : Jeffrey Michael Mode
language : en
Publisher:
Release Date : 2010
Simulation Of The Flow Over A Flat Dimpled Plate written by Jeffrey Michael Mode and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2010 with Boundary layer control categories.
Passive flow control achieved by surface dimpling can be an effective strategy for reducing drag around bluff bodies - an example of substantial popular interest being the flow around a golf ball. While the general effect of dimples causing a delay of boundary layer separation is well known, the mechanisms contributing to this phenomena are subtle and not thoroughly understood. Numerical models offer a powerful approach for studying drag reduction, however simulation strategies are challenged by complex geometries, and in applications the introduction of ad hoc turbulence models which introduce additional uncertainty. These and other factors provide much of the motivation for the current study, which focused on the numerical simulations of the flow over a simplified configuration consisting of a dimpled flat plate. The principal goals of the work are to understand the performance of the numerical methodology, and gain insight into the underlying physics of the flow. Direct numerical simulation of the incompressible Navier-Stokes equations using a fractional step method was employed, with the dimpled flat plate represented using an immersed boundary method. The dimple geometry utilizes a fixed dimple aspect ratio, with dimples arranged in a single spanwise row. The grid sizes considered ranged from approximately 3 to 99 million grid points. Reynolds numbers of 3000 and 4000 based on the inlet laminar boundary layer thickness were simulated. A turbulent boundary layer was induced downstream of the dimples for Reynolds numbers which did not transition for the flow over an undimpled flat plate. First and second order statistics of the boundary layer that develops agree reasonably well with those for turbulent channel flow and flat plate boundary layers in the sublayer and buffer layers, but differ in the outer layer. Inspection of flow visualizations suggest that early transition is promoted by thinning of the boundary layer, initiation of shear layer instabilities over the dimples, flow separation and reattachment, and tripping of the boundary layer at the trailing edge of the dimples.
Direct Numerical Simulation Of Turbulent Flow Over A Dimpled Flat Plate Using An Immersed Boundary Technique
DOWNLOAD
Author : Jeremiah J. Gutierrez-Jensen
language : en
Publisher:
Release Date : 2011
Direct Numerical Simulation Of Turbulent Flow Over A Dimpled Flat Plate Using An Immersed Boundary Technique written by Jeremiah J. Gutierrez-Jensen and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2011 with Computational fluid dynamics categories.
Many methods of passive flow control rely on changes to surface morphology. Roughening surfaces to induce boundary layer transition to turbulence and in turn delay separation is a powerful approach to lowering drag on bluff bodies. While the influence in broad terms of how roughness and other means of passive flow control to delay separation on bluff bodies is known, basic mechanisms are not well understood. Of particular interest for the current work is understanding the role of surface dimpling on boundary layers. A computational approach is employed and the study has two main goals. The first is to understand and advance the numerical methodology utilized for the computations. The second is to shed some light on the details of how surface dimples distort boundary layers and cause transition to turbulence. Simulations are performed of the flow over a simplified configuration: the flow of a boundary layer over a dimpled flat plate. The flow is modeled using an immersed boundary as a representation of the dimpled surface along with direct numerical simulation of the Navier-Stokes equations. The dimple geometry used is fixed and is that of a spherical depression in the flat plate with a depth-to-diameter ratio of 0.1. The dimples are arranged in staggered rows separated by spacing of the center of the bottom of the dimples by one diameter in both the spanwise and streamwise dimensions. The simulations are conducted for both two and three staggered rows of dimples. Flow variables are normalized at the inlet by the dimple depth and the Reynolds number is specified as 4000 (based on freestream velocity and inlet boundary layer thickness). First and second order statistics show the turbulent boundary layers correlate well to channel flow and flow of a zero pressure gradient flat plate boundary layers in the viscous sublayer and the buffer layer, but deviates further away from the wall. The forcing of transition to turbulence by the dimples is unlike the transition caused by a naturally transitioning flow, a small perturbation such as trip tape in experimental flows, or noise in the inlet condition for computational flows.
Numerical Simulation Of Flow Over A Circular Cylinder Between Two Flat Plates
DOWNLOAD
Author : Idir Azouz
language : en
Publisher:
Release Date : 1984
Numerical Simulation Of Flow Over A Circular Cylinder Between Two Flat Plates written by Idir Azouz and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1984 with Mechanical engineering categories.
Recent Advances In Mechanical Infrastructure
DOWNLOAD
Author : Ajit Kumar Parwani
language : en
Publisher: Springer Nature
Release Date : 2022-01-03
Recent Advances In Mechanical Infrastructure written by Ajit Kumar Parwani and has been published by Springer Nature this book supported file pdf, txt, epub, kindle and other format this book has been release on 2022-01-03 with Technology & Engineering categories.
The book presents latest research-based innovations in the field of mechanical infrastructure presented in the International Conference on Recent Advances in Mechanical Infrastructure (ICRAM 2021). The broad research topics presented in this book are recent advances in thermal infrastructure: This includes aerodynamics, renewable energy, computational fluid dynamics, carbon dioxide capture and sequestration, energy and thermo-fluids, fluid dynamics, fuels and combustion, heat and mass transfer, internal combustion engine, and refrigeration and air conditioning. Recent advances in manufacturing infrastructure includes green manufacturing, instrumentation and control, material characterization, manufacturing techniques, rapid prototyping, polymers, and composites. Recent advances in infrastructure planning and design includes applied mechanics, bio-mechanics, computer-aided engineering design, finite element analysis, industrial tribology, machine design, robotics and automation, dynamics and vibration, industrial engineering, and optimization.
Numerical Modeling And Simulation Of Particulate Fouling On Structured Heat Transfer Surfaces Using Multiphase Eulerian Lagrangian Les
DOWNLOAD
Author : Robert Kasper
language : en
Publisher: Cuvillier Verlag
Release Date : 2021-04-30
Numerical Modeling And Simulation Of Particulate Fouling On Structured Heat Transfer Surfaces Using Multiphase Eulerian Lagrangian Les written by Robert Kasper and has been published by Cuvillier Verlag this book supported file pdf, txt, epub, kindle and other format this book has been release on 2021-04-30 with Technology & Engineering categories.
Durch die gezielte Strukturierung von wärmeübertragenden Oberflächen, wie beispielsweise durch Dellen oder Rippen, kann die örtliche Turbulenz und damit die thermische Durchmischung gesteigert werden. Dies kann die Effizienz von Wärmeübertragern oder Bauteilkühlsystemen erheblich erhöhen. Derartige Oberflächenstrukturrierungen begünstigen jedoch das Partikelfouling, daher die Ablagerung suspendierter Partikel, wie z.B. Sand, Schlamm oder Korrosionsprodukte. Gegenstand dieser Arbeit ist die Entwicklung eines universellen, numerischen CFD-Verfahrens zur Vorhersage des partikulären Foulings auf strukturierten Oberflächen, speziell Dellenoberflächen. Das entwickelte Verfahren basiert auf einer Kombination des Lagrangian-Particle-Trackings zur Beschreibung der dispersen Phase (Foulingpartikel), sowie räumlich und zeitlich aufgelöster Large-Eddy Simulation für die Berechnung der kontinuierlichen Phasen (Trägerfluid). Dieses Vorgehen ermöglicht nicht nur die Auswertung der infolge der Partikelablagerungen verminderten thermo-hydraulischen Effizienz, sondern auch die Untersuchung der Wechselwirkungen zwischen turbulenten Strömungsstrukturen und dem partikulärem Fouling. Dadurch kann gezeigt werden, dass die Verwendung von sphärischen Dellen als Oberflächenstrukturen nicht nur aus thermo-hydraulischer Sicht die optimale Wahl darstellt, sondern auch eine substantielle Verminderung des Partikelfoulings begünstigt. The application of structured heat transfer surfaces, such as dimples or ribs, increase the local turbulence and thus thermal mixing. This can improve the efficiency of heat exchangers or cooling systems significantly. However, structured surfaces are known to promote particulate fouling, hence the unwanted accumulation and deposition of suspended particles (e.g., silt, sludge or iron oxide). The scope of this work is the development of a universal numerical CFD method for the prediction of particulate fouling, especially on dimpled surfaces. The proposed approach is based on a combination of the Lagrangian point-particle tracking for the description of the disperse phase (fouling particles), and spatially and temporally resolved large-eddy simulations for the calculation of the continuous phase (carrier fluid). This approach allows not only the evaluation of the reduced thermo-hydraulic efficiency due to particle deposition, but also the investigation of the interaction between turbulent flow structures and the particulate fouling. It can be shown that the usage of spherical dimples as surface structures is not only the optimal choice from a thermo-hydraulic point of view, but also favors a substantial reduction of particulate fouling.
Simulation Of Potential Flow Disturbances On A Flat Plate Using A Microcomputer
DOWNLOAD
Author : Craig Hawkins
language : en
Publisher:
Release Date : 1990
Simulation Of Potential Flow Disturbances On A Flat Plate Using A Microcomputer written by Craig Hawkins and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1990 with categories.
Selected Papers From Pres 2018
DOWNLOAD
Author : Jiří Jaromír Klemeš
language : en
Publisher: MDPI
Release Date : 2020-06-17
Selected Papers From Pres 2018 written by Jiří Jaromír Klemeš and has been published by MDPI this book supported file pdf, txt, epub, kindle and other format this book has been release on 2020-06-17 with Science categories.
The depletion of natural energy resources provides evidential adverse impacts on world economy functionality. The strong requirement of a sustainable energy supply has escalated intensive research and the discovery of cleaner energy sources, as well as efficient energy management practices. In the context of a circular economy, this research not only targets the optimisation of resources utilisation at different stages but also emphasises the eco-design of products to extend production life spans. Based on this concept, this book discusses the roles of process integration approaches, renewable energy sources utilisation and design modifications in addressing the process energy and exergy efficiency improvement. The primary focus is to enhance the economic and environmental performance through process analysis, modelling and optimisation. The articles mainly show the contribution of each aspect: (a) design and numerical study for innovative energy-efficient technologies, (b) process integration—heat and power, (c) process energy efficiency or emission analysis, and (d) optimisation of renewable energy resources’ supply chain. The articles are based on the latest contribution of this journal’s Special Issues in the 21st conference entitled “Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction (PRES)”. This book is complemented with an editorial review to highlight the broader state-of-the-art development.
Control And Identification Of The Flow Past A Flat Plate With Discrete Vortex Simulations
DOWNLOAD
Author : Yen-Cheng Chen
language : en
Publisher:
Release Date : 1997
Control And Identification Of The Flow Past A Flat Plate With Discrete Vortex Simulations written by Yen-Cheng Chen and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1997 with categories.
Selected Problems In Fluid Flow And Heat Transfer
DOWNLOAD
Author : Artur J. Jaworski
language : en
Publisher: MDPI
Release Date : 2019-09-20
Selected Problems In Fluid Flow And Heat Transfer written by Artur J. Jaworski and has been published by MDPI this book supported file pdf, txt, epub, kindle and other format this book has been release on 2019-09-20 with Technology & Engineering categories.
Fluid flow and heat transfer processes play an important role in many areas of science and engineering, from the planetary scale (e.g., influencing weather and climate) to the microscopic scales of enhancing heat transfer by the use of nanofluids; understood in the broadest possible sense, they also underpin the performance of many energy systems. This topical Special Issue of Energies is dedicated to the recent advances in this very broad field. This book will be of interest to readers not only in the fields of mechanical, aerospace, chemical, process and petroleum, energy, earth, civil ,and flow instrumentation engineering but, equally, biological and medical sciences, as well as physics and mathematics; that is, anywhere that “fluid flow and heat transfer” phenomena may play an important role or be a subject of worthy research pursuits.
Numerical Simulation Of 2d Flow Past A Dimpled Cylinder Using A Pseudospectral Method
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2001
Numerical Simulation Of 2d Flow Past A Dimpled Cylinder Using A Pseudospectral Method written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2001 with categories.
February 2007.
