Download or read book Measurement and Computation of Supersonic Flow in a Lobed Diffuser Mixer for Trapped Vortex Combustors written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-03 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The trapped vortex combustor (TVC) pioneered by Air Force Research Laboratories (AFRL) is under consideration as an alternative to conventional gas turbine combustors. The TVC has demonstrated excellent operational characteristics such as high combustion efficiency, low NO(x) emissions, effective flame stabilization, excellent high-altitude relight capability, and operation in the lean-burn or rich burn-quick quench-lean burn (RQL) modes of combustion. It also has excellent potential for lowering the engine combustor weight. This performance at low to moderate combustor mach numbers has stimulated interest in its ability to operate at higher combustion mach number, and for aerospace, this implies potentially higher flight mach numbers. To this end, a lobed diffuser-mixer that enhances the fuel-air mixing in the TVC combustor core was designed and evaluated, with special attention paid to the potential shock system entering the combustor core. For the present investigation, the lobed diffuser-mixer combustor rig is in a full annular configuration featuring sixfold symmetry among the lobes, symmetry within each lobe, and plain parallel, symmetric incident flow. During hardware cold-flow testing, significant discrepancies were found between computed and measured values for the pitot-probe-averaged static pressure profiles at the lobe exit plane. Computational fluid dynamics (CFD) simulations were initiated to determine whether the static pressure probe was causing high local flow-field disturbances in the supersonic flow exiting the diffuser-mixer and whether shock wave impingement on the pitot probe tip, pressure ports, or surface was the cause of the discrepancies. Simulations were performed with and without the pitot probe present in the modeling. A comparison of static pressure profiles without the probe showed that static pressure was off by nearly a factor of 2 over much of the radial profile, even when taking into account potential axial displacement of the prob
Download or read book Measurement and Computation of Supersonic Flow in a Lobed Diffuser mixer for Trapped Vortex Combustors written by Andreja Brankovic and published by . This book was released on 2002 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MEASUREMENT AND COMPUTATION OF SUPERSONIC FLOW IN A LOBED DIFFUSER MIXER FOR TRAPPED VORTEX COMBUSTORS NASA TM 2002 211127 NATIONAL A written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 2004 with total page 1004 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Vortex Dynamics Studies in Supersonic Flow written by Fabrizio Vergine and published by . This book was released on 2014 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite the recognized importance of streamwise vortices in the enhancement of fuel/air mixing processes in scramjet combustors, the effects of their interactions and dynamics on mixing and associated total pressure losses are still relatively unexplored. This work presents the first systematic effort to find answers to fundamental questions such as: can selected vortex interactions be identified and effectively used in an injection system for scramjets? Is the increase of streamwise vorticity content, regardless of its spatial distribution in the flow, always beneficial for entrainment and molecular mixing? Is it possible to apply vortex dynamics concepts in reacting flows? For this reason the dissertation covers the study of selected vortex interaction scenarios both in cold and high enthalpy reacting flows. Specifically, the experimental results and the analysis of the flowfields resulting from two selected supersonic vortex interaction modes in a Mach 2.5 cold flow are presented. Additionally, the experiment design based on vortex dynamics concepts and the reacting plume survey of two pylon injectors in a Mach 2.4 high enthalpy flow are shown. The cold flow experiments were conducted in the supersonic wind tunnel of the Aerodynamics Research Center at the University of Texas at Arlington. A strut injector equipped with specified ramp configurations was designed and used to produce the flowfields of interest. The reacting flow experiments were conducted in the Expansion Tube Facility located in the High Temperature Gasdynamics Laboratory of Stanford University. A detailed description of the supersonic wind tunnel, the instrumentation, the strut injector and the supersonic wake flow downstream is shown as part of the characterization of the facility. As stereoscopic particle image velocimetry was the principal flow measurement technique used in this work to probe the streamwise vortices shed from ramps mounted on the strut, this dissertation provides a deep overview of the challenges and the application of the aforementioned technique to the survey of vortical flows. Moreover, the dissertation provides a new and comprehensive analysis of the flow physics associated with these complex supersonic vortical interactions. The mean and fluctuating velocity flowfields of two selected vortex dynamics scenarios, chosen based on the outcomes of the simulations of an inviscid reduced order model developed in the research group, are presented. The same streamwise vortices (strength, size and Reynolds number) were used experimentally to investigate both a case in which the resulting dynamics evolve in a vortex merging scenario and a case in which the merging process is voluntarily avoided in order to focus the analysis on the fundamental differences associated with the amalgamation processes alone. The results from the mean flow highlight major differences between the two cases and corroborate the use of an inviscid model for the prediction of the main flow physics in the times scales considered. The analysis is also extended to turbulence quantities and concepts borrowed from incompressible turbulence theory (i.e., fluctuating Mach numbers “ 1) appear to explain interesting features of the fluctuating flowfields. Once the interactions among the vortical structures in cold flow were assessed, these vortex dynamics concepts were probed in a reacting environment. The dissertation describes the design phase of two pylon injectors based on the prediction capabilities of the aforementioned model. Then, the results of a set of combustion experiments conducted utilizing hydrogen fuel injected into a Mach 2.4, high-enthalpy (2.8 MJ/kg) air flow are discussed. The results show that, for the heat release levels considered in this study, the morphology of the plume and its evolution are remarkably close to the results produced by the model, enabling an interpretation based on vortex dynamics considerations. The persistence of the streamwise vortical structures created by the selected ramp configurations is shown together with the effectiveness of the coherent structures in successfully anchoring the flame very close to the injection point. The work shows the possibility of a new approach in the design of injection strategies (not limited to injection devices) suitable for adoption in scramjet combustors based on the ability to predict, with basic vortex dynamics concepts and a highly reduced computational cost, the main features of flows of technological interest.
Download or read book A Computational Investigation of Mixing and Reacting Flows in Supersonic Combustors written by D. W. Riggins and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Resolution Measurements of Supersonic Shear Flow Mixing and Combustion written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An initial experimental study of the effects of compressibility on the outer variable scalings and large-scale structure of a supersonic coflowing turbulent jet operating in the wake-like mode was completed. The results showed that the large-scale structure is clearly evident in the downstream portion of the flow, where the convective Mach number has become subsonic. However the structures appear to be suppressed in the upstream portion of the flow, at supersonic convective Mach numbers. The results also showed that the local flow width and growth rate in the downstream portions of the flow are good in agreement with the scaling laws for the corresponding incompressible flow.
Download or read book AIAA Journal written by American Institute of Aeronautics and Astronautics and published by . This book was released on 2003 with total page 938 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA SP written by and published by . This book was released on 1985 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeronautical Engineering written by and published by . This book was released on 1985 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
Download or read book Gas Turbine Engineering Handbook written by Meherwan P. Boyce and published by Elsevier. This book was released on 2017-09-01 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gas Turbine Engineering Handbook has been the standard for engineers involved in the design, selection, and operation of gas turbines. This revision includes new case histories, the latest techniques, and new designs to comply with recently passed legislation. By keeping the book up to date with new, emerging topics, Boyce ensures that this book will remain the standard and most widely used book in this field. The new Third Edition of the Gas Turbine Engineering Hand Book updates the book to cover the new generation of Advanced gas Turbines. It examines the benefit and some of the major problems that have been encountered by these new turbines. The book keeps abreast of the environmental changes and the industries answer to these new regulations. A new chapter on case histories has been added to enable the engineer in the field to keep abreast of problems that are being encountered and the solutions that have resulted in solving them. - Comprehensive treatment of Gas Turbines from Design to Operation and Maintenance. In depth treatment of Compressors with emphasis on surge, rotating stall, and choke; Combustors with emphasis on Dry Low NOx Combustors; and Turbines with emphasis on Metallurgy and new cooling schemes. An excellent introductory book for the student and field engineers - A special maintenance section dealing with the advanced gas turbines, and special diagnostic charts have been provided that will enable the reader to troubleshoot problems he encounters in the field - The third edition consists of many Case Histories of Gas Turbine problems. This should enable the field engineer to avoid some of these same generic problems
Download or read book The Gas Turbine Handbook written by Tony Giampaolo and published by The Fairmont Press, Inc.. This book was released on 2003 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of a bestseller, this comprehensive reference provides the fundamental information required to understand both the operation and proper application of all types of gas turbines. The completely updated second edition adds a new section on use of inlet cooling for power augmentation and NOx control. It explores the full spectrum of gas turbines hardware, typical application scenarios, and operating parameters, controls, inlet treatments, inspection, trouble-shooting, and more. The author discusses strategies that can help readers avoid problems before they occur and provides tips that enable diagnosis of problems in their early stages and analysis of failures to prevent their recurrence.
Download or read book Design and Development of Aerospace Vehicles and Propulsion Systems written by S. Kishore Kumar and published by Springer Nature. This book was released on 2021-03-18 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents selected papers presented in the Symposium on Applied Aerodynamics and Design of Aerospace Vehicles (SAROD 2018), which was jointly organized by Aeronautical Development Agency (the nodal agency for the design and development of combat aircraft in India), Gas-Turbine Research Establishment (responsible for design and development of gas turbine engines for military applications), and CSIR-National Aerospace Laboratories (involved in major aerospace programs in the country such as SARAS program, LCA, Space Launch Vehicles, Missiles and UAVs). It brings together experiences of aerodynamicists in India as well as abroad in Aerospace Vehicle Design, Gas Turbine Engines, Missiles and related areas. It is a useful volume for researchers, professionals and students interested in diversified areas of aerospace engineering.
Download or read book Airframe and Powerplant Mechanics Airframe Handbook written by United States. Flight Standards Service and published by . This book was released on 1976 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Propulsion and Power written by Joachim Kurzke and published by Springer. This book was released on 2018-05-28 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is written for engineers and students who wish to address the preliminary design of gas turbine engines, as well as the associated performance calculations, in a practical manner. A basic knowledge of thermodynamics and turbomachinery is a prerequisite for understanding the concepts and ideas described. The book is also intended for teachers as a source of information for lecture materials and exercises for their students. It is extensively illustrated with examples and data from real engine cycles, all of which can be reproduced with GasTurb (TM). It discusses the practical application of thermodynamic, aerodynamic and mechanical principles. The authors describe the theoretical background of the simulation elements and the relevant correlations through which they are applied, however they refrain from detailed scientific derivations.
Download or read book Computational Fluid Dynamics written by Takeo Kajishima and published by Springer. This book was released on 2016-10-01 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook presents numerical solution techniques for incompressible turbulent flows that occur in a variety of scientific and engineering settings including aerodynamics of ground-based vehicles and low-speed aircraft, fluid flows in energy systems, atmospheric flows, and biological flows. This book encompasses fluid mechanics, partial differential equations, numerical methods, and turbulence models, and emphasizes the foundation on how the governing partial differential equations for incompressible fluid flow can be solved numerically in an accurate and efficient manner. Extensive discussions on incompressible flow solvers and turbulence modeling are also offered. This text is an ideal instructional resource and reference for students, research scientists, and professional engineers interested in analyzing fluid flows using numerical simulations for fundamental research and industrial applications.
Download or read book Advances in Applied Mechanical Engineering written by Hari Kumar Voruganti and published by Springer Nature. This book was released on 2020-02-01 with total page 1161 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents select peer reviewed proceedings of the International Conference on Applied Mechanical Engineering Research (ICAMER 2019). The books examines various areas of mechanical engineering namely design, thermal, materials, manufacturing and industrial engineering covering topics like FEA, optimization, vibrations, condition monitoring, tribology, CFD, IC engines, turbo-machines, automobiles, manufacturing processes, machining, CAM, additive manufacturing, modelling and simulation of manufacturing processing, optimization of manufacturing processing, supply chain management, and operations management. In addition, recent studies on composite materials, materials characterization, fracture and fatigue, advanced materials, energy storage, green building, phase change materials and structural change monitoring are also covered. Given the contents, this book will be useful for students, researchers and professionals working in mechanical engineering and allied fields.
