Download or read book A Computational Study of Flow Over a 6 1 Prolate Spheroid at Incidence written by Samuel Johnson and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the results of computational fluid dynamics (CFD) simulations predicting the overall forces and moments acting on an inclined 6:1 prolate spheroid in crossflow. Reynolds-averaged Navier-Stokes (RANS) was used to simulate flows with Reynolds numbers ranging from 1.39 million to 4.2 million at three inclination angles, 10, 20, and 30 degrees. The RANS cases used the k-omega shear-stress-transport (SST) turbulence model, though the k-epsilon and Spalart-Allmaras models were also used for comparison in certain cases. Three mesh types: structured overset, unstructured, and trimmed Cartesian were applied to the flow cases described above and their results compared. The RANS results agreed with experimental data best at the highest Reynolds number, matching pitching moments within 3% across the range of incidence angles considered. The k-omega SST model proved the best suited of the turbulence models to accurately reproduce the flow when compared to experiments. The three turbulence models produced similar results with only marginal differences. Wall-modeled large eddy simulation (WMLES) was also used to simulate flow for the 20-degree case at a Reynolds number of 4.2 million. A grid study was carried out with the structured WMLES grids to assess the sensitivity of the wall model to initial wall spacing. The variation in initial wall spacing resulted a 5% difference in the normal force predictions as well as a 10-degree shift in the azimuthal separation location along the length of the prolate spheroid.
Download or read book An Experimental Study of Flow Over a 6 to 1 Prolate Spheroid at Incidence written by Seungki Ahn and published by . This book was released on 1992 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: In two-dimensional flow, the point of flow separation from the surface coincides with the point at which the skin friction vanishes. However, in three-dimensional flow, the situation is much more complex and the flow separation is rarely associated with the vanishing of the wall shear stress except in a few special cases. Though the effects of cross-plane separation are substantial and have been recognised for some time, the phenomenon of flow separation over three-dimensional bodies is still far from being completely understood. The flow is so complex that no completely satisfactory analytical tools are available at the moment. In an attempt to logically identify the various effects and parametric dependence while simultaneously minimizing configuration dependent issue, the flow over a 6 to 1 prolate spheroid, which is a generic three-dimensional body, is investigated.
Download or read book Computational and Experimental Study of Three Dimensional Separated Flow Structure Over Prolate Spheroids written by Steven M. Harrington and published by . This book was released on 1995 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 1948 with total page 400 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 Application of Modern Turbulence Models to Vortical Flow Around a 6 1 Prolate Spheroid at Incidence written by S.-E. Kim 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 Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 41st AIAA Aerospace Sciences Meeting Exhibit written by and published by . This book was released on 2003 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Fluid Dynamics Techniques written by Fathi Habashi and published by CRC Press. This book was released on 1995-11-22 with total page 930 pages. Available in PDF, EPUB and Kindle. Book excerpt: First published in 1995. Routledge is an imprint of Taylor & Francis, an informa company.
Download or read book 43rd AIAA Aerospace Sciences Meeting Exhibit written by and published by . This book was released on 2005 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Mechanics written by Zhenhan Yao and published by 清华大学出版社有限公司. This book was released on 2004 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Differential Reynolds Stress Modeling for Separating Flows in Industrial Aerodynamics written by Bernhard Eisfeld and published by Springer. This book was released on 2015-03-24 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recent progress in the application of RANS turbulence models based on the Reynolds stress transport equations. A variety of models has been implemented by different groups into different flow solvers and applied to external as well as to turbo machinery flows. Comparisons between the models allow an assessment of their performance in different flow conditions. The results demonstrate the general applicability of differential Reynolds stress models to separating flows in industrial aerodynamics.
Download or read book AIAA Journal written by American Institute of Aeronautics and Astronautics and published by . This book was released on 2006 with total page 958 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unsteady Flow Over a 6 1 Prolate Spheroid written by Todd G. Wetzel and published by . This book was released on 2002* with total page 984 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flow over a 6:1 prolate spheroid undergoing time dependent maneuvers is studied. The model is mounted on the Dynamic Plunge-Pitch-Roll (DyPPiR) model mount in the Virginia Tech Stability wind Tunnel. The model undergoes 30° pitchup namps in 0.333s and a 13.5° submarine maneuver in 0.25s. All tests are done at Reynolds number of 4.2 million. Unsteady surface pressure, skin friction, and force and moment measurements are documented for these two maneuvers. In particular, time dependent separation locations are documented for the first time.
Download or read book Aeronautical Engineering written by and published by . This book was released on 1991 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
