Download or read book Characterization of the Far wake of a 6 1 Prolate Spheroid written by Jonathan P. Peck and published by . This book was released on 2020 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Even with the dramatic advances in computational power seen in the last decades, Computational Fluid Dynamics (CFD) models are as yet unable to predict transition, separation, and wake development for fluid flow over three-dimensional bodies to the desired level of accuracy in an acceptable amount of time. Without the ability to predict forces and moments experienced by the body, critical parameters such as drag and loads on control surfaces for air- and water-borne vehicles cannot be predicted. The prolate spheroid has long been a popular body upon which to verify CFD models because of its simple geometry and three-dimensional flow field. Advances in computational speed and experimental capabilities have prompted a renewed interest in related research. An experiment was conducted in the large towing tank facility of the U.S. Naval Academy, using a 6:1 prolate spheroid, measuring 54 in. (1.4 m) in length and 9 in. (0.23 m) in diameter. The spheroid model was inclined by 15° relative to the undisturbed free surface, and towed at speeds yielding length-based Reynolds numbers from 0.5-4.2 x 106. The results from the 0.5 x 106 case are presented in the present discussion. A stationary stereo particle image velocimetry (SPIV) system was designed for the experiment and used to provide two-dimensional velocity maps in two spatial-dimensions (2C2D). These time histories show the trajectory of the wake as it leaves the tail of the model, the expansion of the wake width, the size, strength, and position of the primary vortical structures shed into the wake. These results will inform follow-on studies focused on measuring turbulent quantities in the far wake." -- Report Documentation Page [Standard Form 298 (Rev. 8-98)].
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1971 with total page 804 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 A Detailed Investigation of the 3 D Separation about a 6 1 Prolate Spheroid at Angle of attack written by Christopher J. Chesnakas and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AIAA Journal written by American Institute of Aeronautics and Astronautics and published by . This book was released on 1999 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation based Analyses of Turbulent Wakes written by Sheel Nidhan and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulent wakes are pervasive in man-made and natural environments. In the ocean and the atmosphere, these wakes interact with the background ambient stratification to give rise to a myriad of interesting phenomena, e.g., multistage decay of mean and turbulence, long-lived coherent structures, and the appearance of internal gravity waves, to name a few. With the rise in supercomputing power, high-fidelity numerical simulations have become an increasingly feasible way to investigate the phenomenology of these wakes. As these simulations become commonplace in research, there is an increased focus on the use of data-driven techniques to uncover the rich dynamics from the obtained datasets. This dissertation is an examination of turbulent wakes using data-driven techniques and numerical simulations. In the first part, spectral proper orthogonal decomposition is used to investigate a turbulent disk wake database at Re = 5 x 104 and Fr = [infinity], 10, 2. We first study the evolution of the vortex shedding mode and double helix mode in the unstratified wake (Fr = [infinity]), building on and refining the previous experimental studies. Thereafter, the SPOD analysis of the stratified wakes is performed that uncovers two new results: (a) coherence originating at the body gets stronger and lives longer with progressively increasing stratification levels and (b) for Fr [greater than and approximately equal to] 2, vortex shedding is the dominant mechanism of internal gravity wave generation. In the second part of the work, large eddy simulations (LES) are used to investigate the flow past a prolate 6:1 spheroid. Firstly, high-resolution hybrid simulation is used to simulate the far wake of a 6:1 spheroid at 0-degree angle of attack and Re = 105, Fr = 2 and 10. The far wake is compared to the above-mentioned disk database. The spheroid wakes show differences in locations at which mean wake transitions take place. These differences are explained in light of energy budgets. Secondly, large eddy simulations of flow past a 6:1 spheroid at Re = 5000, Fr = [infinity], 6, 1.9, 1, and a moderate angle of attack [alpha] = 10[superscript circle] are carried out. Body forces, mean wake and vorticity dynamics, and flow spectra are analyzed in detail and presented in the dissertation.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Modelling of Bifurcations and Instabilities in Fluid Dynamics written by Alexander Gelfgat and published by Springer. This book was released on 2018-07-06 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt: Instabilities of fluid flows and the associated transitions between different possible flow states provide a fascinating set of problems that have attracted researchers for over a hundred years. This book addresses state-of-the-art developments in numerical techniques for computational modelling of fluid instabilities and related bifurcation structures, as well as providing comprehensive reviews of recently solved challenging problems in the field.
Download or read book Laminar turbulent Transition written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development and published by . This book was released on 1977 with total page 414 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 1993 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Report for the Year written by National Physical Laboratory (Great Britain) and published by . This book was released on 1925 with total page 1114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vol. for 1905- include lists of papers published by the laboratory or communicated by members of the staff to scientific societies or to the technical journals.
Download or read book Twenty First Symposium on Naval Hydrodynamics written by National Research Council and published by National Academies Press. This book was released on 1997-09-11 with total page 1100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transactions of the Royal Institution of Naval Architects written by Royal Institution of Naval Architects and published by . This book was released on 1988 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: List of members in each volume.
Download or read book Particle Image Velocimetry written by Ronald J. Adrian and published by Cambridge University Press. This book was released on 2011 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particle image velocimetry, or PIV, refers to a class of methods used in experimental fluid mechanics to determine instantaneous fields of the vector velocity by measuring the displacements of numerous fine particles that accurately follow the motion of the fluid. Although the concept of measuring particle displacements is simple in essence, the factors that need to be addressed to design and implement PIV systems that achieve reliable, accurate, and fast measurements and to interpret the results are surprisingly numerous. The aim of this book is to analyze and explain them comprehensively.
Download or read book Twenty Second Symposium on Naval Hydrodynamics written by National Research Council and published by National Academies Press. This book was released on 2000-03-02 with total page 1039 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Twenty-Second Symposium on Naval Hydrodynamics was held in Washington, D.C., from August 9-14, 1998. It coincided with the 100th anniversary of the David Taylor Model Basin. This international symposium was organized jointly by the Office of Naval Research (Mechanics and Energy Conversion S&T Division), the National Research Council (Naval Studies Board), and the Naval Surface Warfare Center, Carderock Division (David Taylor Model Basin). This biennial symposium promotes the technical exchange of naval research developments of common interest to all the countries of the world. The forum encourages both formal and informal discussion of the presented papers, and the occasion provides an opportunity for direct communication between international peers.
Download or read book Supplementary Report and Scheme of Work for the Year 1919 1920 written by National Physical Laboratory (Great Britain) and published by . This book was released on 1924 with total page 1106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1905-51 include lists of reports and papers published by the laboratory.
Download or read book Keywords Index to U S Government Technical Reports written by and published by . This book was released on 1963-06-15 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
