Author: Publisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 68
Book Description
Direct Simulation of High-speed Mixing Layers
Author: Direct Simulation of High-speed Mixing Layers
Author: H. S. MukundaCombustion in High-Speed Flows
Author: John BuckmasterPublisher: Springer Science & Business Media
ISBN: 9401110506
Category : Technology & Engineering
Languages : en
Pages : 639
Book Description
This volume contains the proceedings of the Workshop on Com bustion, sponsored by the Institute for Computer Applications in Science and Engineering (ICASE) and the NASA Langley Research Center (LaRC). It was held on October 12-14, 1992, and was the sec ond workshop in the series on the subject. The first was held in 1989, and its proceedings were published by Springer-Verlag under the title "Major Research Topics in Combustion," edited by M. Y. Hussaini, A. Kumar, and R. G. Voigt. The focus of the second workshop was directed towards the development, analysis, and application of basic models in high speed propulsion of particular interest to NASA. The exploration of a dual approach combining asymptotic and numerical methods for the analysis of the models was particularly encouraged. The objectives of this workshop were i) the genesis of models that would capture or reflect the basic pllysical phenomena in SCRAMJETs and/or oblique detonation-wave engines (ODWE), and ii) the stimulation of a greater interaction between NASA exper imental research community and the academic community. The lead paper by D. Bushnell on the status and issues of high speed propulsion relevant to both the SCRAMJET and the ODWE parallels his keynote address which set the stage of the workshop. Following the lead paper were five technical sessions with titles and chairs: Experiments (C. Rogers), Reacting Free Shear Layers (C. E. Grosch), Detonations (A. K. Kapila), Ignition and Struc ture (J. Buckmaster), and Unsteady Behaviour ('1'. L. Jackson).
Compressibility, Turbulence and High Speed Flow
Author: Thomas B. GatskiPublisher: Elsevier
ISBN: 0080559123
Category : Science
Languages : en
Pages : 296
Book Description
This book introduces the reader to the field of compressible turbulence and compressible turbulent flows across a broad speed range through a unique complimentary treatment of both the theoretical foundations and the measurement and analysis tools currently used. For the computation of turbulent compressible flows, current methods of averaging and filtering are presented so that the reader is exposed to a consistent development of applicable equation sets for both the mean or resolved fields as well as the transport equations for the turbulent stress field. For the measurement of turbulent compressible flows, current techniques ranging from hot-wire anemometry to PIV are evaluated and limitations assessed. Characterizing dynamic features of free shear flows, including jets, mixing layers and wakes, and wall-bounded flows, including shock-turbulence and shock boundary-layer interactions, obtained from computations, experiments and simulations are discussed. - Describes prediction methodologies including the Reynolds-averaged Navier Stokes (RANS) method, scale filtered methods and direct numerical simulation (DNS) - Presents current measurement and data analysis techniques - Discusses the linkage between experimental and computational results necessary for validation of numerical predictions - Meshes the varied results of computational and experimental studies in both free and wall-bounded flows to provide an overall current view of the field
NASA Scientific and Technical Publications: A Catalog of Special Publications, Reference Publications, Conference Publications, and Technical Papers, 1991-1992
Author: Scientific and Technical Aerospace Reports
Author: Direct Simulation of High-Speed Mixing Layers
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781722357528
Category :
Languages : en
Pages : 68
Book Description
A computational study of a nonreacting high-speed mixing layer is performed. A higher order algorithm with sufficient grid points is used to resolve all relevant scales. In all cases, a temporal free-stream disturbance is introduced. The resulting flow is time-sampled to generate a statistical cross section of the flow properties. The studies are conducted at two convective Mach numbers, three free-stream turbulence intensities, three Reynolds numbers, and two types of initial profiles-hyperbolic tangent (tanh) and boundary layer. The boundary-layer profile leads to more realistic predictions of the transition processes. The predicted transition Reynolds number of 0.18 x 10(exp 6) compares well with experimental data. Normalized vortex spacings for the boundary-layer case are about 3.5 and compare favorably with the 1.5 to 2.5 found in experimental measurements. The tanh profile produces spacings of about 10. The growth rate of the layer is shown to be moderately affected by the initial disturbance field, but comparison with experimental data shows moderate agreement. For the boundary-layer case, it is shown that noise at the Strouhal number of 0.007 is selectively amplified and shows little Reynolds number dependence. Mukunda, H. S. and Sekar, B. and Carpenter, M. H. and Drummond, J. Philip and Kumar, Ajay Langley Research Center...
NASA Technical Paper
Author: United States. National Aeronautics and Space AdministrationPublisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 68
Book Description
High-Performance Computing
Author: R.J. AllanPublisher: Springer Science & Business Media
ISBN: 146154873X
Category : Science
Languages : en
Pages : 567
Book Description
Over the past decade high performance computing has demonstrated the ability to model and predict accurately a wide range of physical properties and phenomena. Many of these have had an important impact in contributing to wealth creation and improving the quality of life through the development of new products and processes with greater efficacy, efficiency or reduced harmful side effects, and in contributing to our ability to understand and describe the world around us. Following a survey ofthe U.K.'s urgent need for a supercomputingfacility for aca demic research (see next chapter), a 256-processor T3D system from Cray Research Inc. went into operation at the University of Edinburgh in the summer of 1994. The High Performance Computing Initiative, HPCI, was established in November 1994 to support and ensure the efficient and effective exploitation of the T3D (and future gen erations of HPC systems) by a number of consortia working in the "frontier" areas of computational research. The Cray T3D, now comprising 512 processors and total of 32 CB memory, represented a very significant increase in computing power, allowing simulations to move forward on a number offronts. The three-fold aims of the HPCI may be summarised as follows; (1) to seek and maintain a world class position incomputational scienceand engineering, (2) to support and promote exploitation of HPC in industry, commerce and business, and (3) to support education and training in HPC and its application.
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