Download or read book Numerical Simulation of Vortex Generating Jets in Zero and Adverse Pressure Gradients written by Curtis Lynn Memory and published by . This book was released on 2007 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical simulations of particle image velocimetry (PIV) experiments conducted with vortex generating jets (VGJs) on a flat plate, at a Reynolds number based on plate length of 50,000, were performed for three flow conditions using a time-accurate hybrid Navier-Stokes solver. Time-averaged steady blowing of angled jets, subjected to a zero pressure gradient, yielded excellent agreement with the PIV data in terms of vortex formation and strength. Observed flow features include primary and secondary vortices, where the primary vortex eventually dominates the downstream region. A shell wall structure, created by smaller vortical structures surrounding the developing vortices, was also observed. A pulsed jet in a zero pressure gradient was then initialized from a no-control case. A qualitative comparison between averaged experimental and instantaneous numerical results was performed with good agreement in terms of the convected size and distance of the wake. Analysis of the instantaneous numerical flow field agreed well with various flow visualization experiments describing the formation of "kidney" vortices. Various indicators point to the production of a primary vortex by the reduced mass flow of the pulsed jet. Finally, an adverse pressure gradient was applied, inducing a laminar separation zone on the plate. A pulsed angled jet induced strong spanwise vortices in the separated shear layer which appear to weaken the separation zone and allow the bulk jet fluid to flush the remaining low-momentum fluid out of the domain. It is reasonable to assume that reduced blowing ratios and duty cycles would produce similar shear layer vortices and comparable loss reductions. Influences of both turbulent transition and dominant vortical structures were observed, though the spanwise shear layer vortices appear to be critical to the laminar separation reduction scenarios observed in this study.
Download or read book Numerical Simulation of Turbulent Jets with Rectangular Cross Section written by Robert V. Wilson and published by . This book was released on 1997 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three-dimensional turbulent jets with rectangular cross-section are simulated with a finite-difference numerical method. The full Navier-Stokes equations are solved at low Reynolds numbers, whereas at the high Reynolds numbers filtered forms of the equations are solved along with a subgrid scale model to approximate effects of the unresolved scales. A 2-N storage, third-order Runge-Kutta scheme is used for temporal discretization and a fourth-order compact scheme is used for spatial discretization. Computations are performed for different inlet conditions which represent different types of jet forcing. The phenomenon of axis-switching is observed, and it is confirmed that this is based on self-induction of the vorticity field. Budgets of the mean streamwise velocity show that convection is balanced by gradients of the Reynolds stresses and the pressure.
Download or read book New Results in Numerical and Experimental Fluid Mechanics VIII written by Andreas Dillmann and published by Springer Science & Business Media. This book was released on 2012-12-27 with total page 747 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the contributions to the 17th Symposium of STAB (German Aerospace Aerodynamics Association). STAB includes German scientists and engineers from universities, research establishments and industry doing research and project work in numerical and experimental fluid mechanics and aerodynamics, mainly for aerospace but also for other applications. Many of the contributions collected in this book present results from national and European Community sponsored projects. This volume gives a broad overview of the ongoing work in this field in Germany and spans a wide range of topics: airplane aerodynamics, multidisciplinary optimization and new configurations, hypersonic flows and aerothermodynamics, flow control (drag reduction and laminar flow control), rotorcraft aerodynamics, aeroelasticity and structural dynamics, numerical simulation, experimental simulation and test techniques, aeroacoustics as well as the new fields of biomedical flows, convective flows, aerodynamics and acoustics of high-speed trains.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Large Scale Simulation written by Dan Chen and published by CRC Press. This book was released on 2012-05-29 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Large-Scale Simulation: Models, Algorithms, and Applications gives you firsthand insight on the latest advances in large-scale simulation techniques. Most of the research results are drawn from the authors’ papers in top-tier, peer-reviewed, scientific conference proceedings and journals. The first part of the book presents the fundamentals of large-scale simulation, including high-level architecture and runtime infrastructure. The second part covers middleware and software architecture for large-scale simulations, such as decoupled federate architecture, fault tolerant mechanisms, grid-enabled simulation, and federation communities. In the third part, the authors explore mechanisms—such as simulation cloning methods and algorithms—that support quick evaluation of alternative scenarios. The final part describes how distributed computing technologies and many-core architecture are used to study social phenomena. Reflecting the latest research in the field, this book guides you in using and further researching advanced models and algorithms for large-scale distributed simulation. These simulation tools will help you gain insight into large-scale systems across many disciplines.
Download or read book Numerical Simulations written by Lutz Angermann and published by BoD – Books on Demand. This book was released on 2010-12-30 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will interest researchers, scientists, engineers and graduate students in many disciplines, who make use of mathematical modeling and computer simulation. Although it represents only a small sample of the research activity on numerical simulations, the book will certainly serve as a valuable tool for researchers interested in getting involved in this multidisciplinary field. It will be useful to encourage further experimental and theoretical researches in the above mentioned areas of numerical simulation.
Download or read book Direct Numerical Simulations and Modeling of Jets in Crossflow written by Suman Muppidi and published by . This book was released on 2006 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Pulsed Vortex Generator Jets for Active Flow Control written by and published by . This book was released on 2003 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flowfields produced by several active and passive flow control devices are being investigated experimentally and numerically as part of co-operative effort between the US Air Force Research Laboratory and the UK's Defense Evaluation & Research Agency (DERA). This manuscript reports the results of an experimental investigation of pulsed vortex generator jets (PVGJs) conducted at DERA's Boundary Layer Facility in Bedford. The focus of these tests was to investigate the influence of jet velocity, pulsing frequency, and duty cycle on the mean characteristics of the flowfield produced by a PVGJ in a turbulent boundary layer. The experiments were conducted in a zero-pressure-gradient flow at a freestream velocity of 32 m/s. The flowfield was explored using a three-component laser Doppler anemometry system, and the information is used to calculate local field properties such as velocity and vorticity as well as global parameters like total circulation. The data give insight into the effectiveness of the VGs in terms of location, strength, and persistence of the generated vortices and their influence on the boundary layer. While the planned computational simulation effort is in its infancy, preliminary steady-jet computational results are compared with the flow field data that has been acquired in the boundary layer facility.
Download or read book Numerical Simulation of Turbulent Jets with Rectangular Cross section written by Robert V. Wilson and published by . This book was released on 1997 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Numerical Simulation of Turbulent Flows written by Ismail Celik and published by . This book was released on 1991 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book IUTAM Symposium on Flow Control and MEMS written by Jonathan F. Morrison and published by Springer Science & Business Media. This book was released on 2010-09-09 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Symposium brought together many of the world’s experts in fluid mechanics, microfabrication and control theory to discover the synergy that can lead to real advances and perhaps find ways in which collaborative projects may proceed. The high profile meeting was attended by keynote speakers who are leaders in their fields. A key driver was the improvement in flow efficiency to reduce drag, and thereby emissions arising from transport. About 65 papers were presented.
Download or read book 91 0705 91 0743 written by and published by . This book was released on 1991 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1985 with total page 864 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation of Non linear Jet Streak Adjustment written by Andrew Hugh Van Tuyl and published by . This book was released on 1981 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Problems in Fluid Flow and Heat Transfer written by Artur J. Jaworski and published by MDPI. This book was released on 2019-09-20 with total page 460 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992-12 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt:
