Download or read book The Shape of Two dimensional Turbulent Wakes in Density stratified Fluids written by Roy Hayden Monroe and published by . This book was released on 1968 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of an analytical and experimental investigation of the rate of growth of the zone of turbulent mixing behind a two-dimensional circular cylinder are presented. The analytical phase of the study formulated a dynamical model for a parcel of fluid subjected to inertia, turbulent damping, and gravity restoring forces. The experiments were conducted in a tank 120 in. long and 4.5 in. wide which was filled to a depth of 18 in. with a fluid having a linear density gradient. The cylinder was towed at mid-depth by a variable speed motor-pulley system. A record of wake growth behind the cylinder was made by means of motion pictures of an aluminum pigment tracer in the fluid. The Reynolds number ranged from 1300 to 3500 and densimetric Froude numbers varied from 5 to 20. The density stratification was found to exert a strong inhibiting force on the wake growth. Using the dynamical model to correlate experimental data, the mixing length in the turbulent zone was found to decrease with increasing density stratification. (Author).
Download or read book The Shape of Two dimensional Turbulent Wakes in Density stratified Fluids written by and published by . This book was released on 1968 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of an analytical and experimental investigation of the rate of growth of the zone of turbulent mixing behind a two-dimensional circular cylinder are presented. The analytical phase of the study formulated a dynamical model for a parcel of fluid subjected to inertia, turbulent damping, and gravity restoring forces. The experiments were conducted in a tank 120 in. long and 4.5 in. wide which was filled to a depth of 18 in. with a fluid having a linear density gradient. The cylinder was towed at mid-depth by a variable speed motor-pulley system. A record of wake growth behind the cylinder was made by means of motion pictures of an aluminum pigment tracer in the fluid. The Reynolds number ranged from 1300 to 3500 and densimetric Froude numbers varied from 5 to 20. The density stratification was found to exert a strong inhibiting force on the wake growth. Using the dynamical model to correlate experimental data, the mixing length in the turbulent zone was found to decrease with increasing density stratification. (Author).
Download or read book TWO DIMENSIONAL TURBULENT WAKES IN DENSITY STRATIFIED LIQUIDS written by John F. Kennedy and published by . This book was released on 1964 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Two dimensional Turbulent Momentum Wakes in Density Stratified Fluids written by Robert Anton Froebel and published by . This book was released on 1964 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulent Wakes in Density Stratified Fluids of Finite Extent written by Edmund A. Prych and published by . This book was released on 1964 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented of an investigation of the effects of a free surface and density stratification of the turbulent transfer of mass and momentum in two-dimensional wakes. The effect of depth of submergence on the drag of a twodimensional body was also investigated.
Download or read book The Growth of a Turbulent Wake in a Density stratified Fluid written by Walter P. M. van de Watering and published by . This book was released on 1966 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The force of gravity causes a turbulent wake in a density-stratified fluid to eventually cease its vertical growth and then to collapse towards its horizontal midplane. In the present investigation this phenomenon was studied experimentally. The turbulent wake was created by means of a spiral paddle, agitated by a pendulum-type arrangement outside a transparent lucite tank. Data were obtained from tracings of the motion pictures taken by a 16 mm movie camera. Both the pendulum arrangement and the paddle diameter were varied to find the possible influence of the experimental conditions. It was observed that the initial rate of growth in the vertical direction is constant, depending primarily on the density gradient and the agitation mechanism (i.e. pendulum and paddle diameter). This initial rate of growth of the wake, the maximum vertical thickness of the wake, the time at which collapse begins and the turbulence intensity within the wake at that time, were all correlated with the Vaisala frequency, resulting in three important constants which seemed to be independent of the experimental conditions. (Author).
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 Experiments on Turbulent Wakes in a Stable Density stratified Environment written by Walter P. M. van de Watering and published by . This book was released on 1969 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a laboratory experiment, turbulent mixed regions were generated in a linearly density-stratified fluid and their behavior was studied. Such regions may occur in nature in the atmosphere and in the ocean. Particularly during their early history, the shape of such regions is influenced by the interacting effects of turbulence and buoyancy, culminating in the occurrence of a maximum thickness and subsequent vertical collapse. A Richardson number (equivalent to the ratio of the characteristic turbulence time and the Vaisala period) was found satisfactorily to correlate the data obtained, together with those previously obtained by other investigators with self-propelled bodies. An estimate is made of the degree of mixing that takes place inside a turbulent mixed region during its growth in stably-stratified surroundings: the effectiveness of this mixing determines the ultimate thickness to which the mixing region collapses. (Author).
Download or read book Turbulence Models and Their Application in Hydraulics written by Wolfgang Rodi and published by CRC Press. This book was released on 1993-01-01 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an introduction to the subject of turbulence modelling in a form easy to understand for anybody with a basic background in fluid mechanics, and it summarizes the present state of the art. Individual models are described and examined for the merits and demerits which range from the simple Prandtl mixing length theory to complex second order closure schemes.
Download or read book Naval Research Reviews written by and published by . This book was released on 1969 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Three dimensional Momentumless Wakes in Density stratified Liquids written by Philip Joseph Stockhausen and published by . This book was released on 1966 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments were performed to investigate the configuration and surface effects of the turbulent wake generated by a self-propelled body moving in a linearly density-stratified liquid. The experiments were performed in a 50-foot long tank filled to a depth of 2 1/2 ft. For all experiments, the Reynolds number, based on the diameter of the circular disc mounted on the model's bow, was 89,000. It was found that the mixed region generated by the turbulent wak5 rapidly attained a maximum vertical extent, and then collapsed vertically while continuing to expand laterally. The vertical collapse of the wake was accompanied by the convergence toward the model of the fluid at the free surface. The convergence did not occur with homogeneous liquids. It was concluded that this surface convergence is possible only if the turbulent wake extends to the free surface. A new method was developed for generating linear density profiles in large tanks. (Author).
Download or read book Technical Report written by Massachusetts Institute of Technology. Hydrodynamics Laboratory and published by . This book was released on 1968-06 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Prediction of Characteristics of Two Dimensional Turbulent Wakes Under the Influence of Streamline Curvature and Zero Positive and Negative Pressure Gradients written by and published by . This book was released on 1996 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Science and High Performance Computing III written by Egon Krause and published by Springer Science & Business Media. This book was released on 2008-10-12 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains 18 contributions to the Third Russian-German Advanced Research Workshop on Computational Science and High Performance Computing presented in July 2007 at Novosibirsk, Russia. The workshop was organized jointly by the High Performance Computing Center Stuttgart (HLRS) and the Institute of Computational Technologies of the Siberian Branch of the Russian Academy of Sciences (ICT SB RAS) The contributions range from computer science, mathematics and high performance computing to applications in mechanical and aerospace engineering. They show a wealth of theoretical work and simulation experience with a potential of bringing together theoretical mathematical modelling and usage of high performance computing systems presenting the state of the art of computational technologies.
Download or read book Hydraulic Research in the United States and Canada 1972 written by Gershon Kulin and published by . This book was released on 1974 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On Wakes in Stratified Fluids written by Gerald S. Janowitz and published by . This book was released on 1967 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: The paper considers two-dimensional flow induced by a body moving with constant speed through a linearly stratified fluid. The solution shows a diffusive wake far upstream of the body. Less far upstream, a system of jets occurs; these jets become stronger and more narrow as the body is approached. An increase in speed or diffusivity weakens these jets. We find at low speeds, low diffusivities, and moderate distances upstream of the body, that the velocity along the x-axis given by the exact solution is well approximated by the upstream asymptotic nondiffusive solution. Far downstream of the body, the solution shows a diffusive wake identical with the far upstream diffusive wake. In the downstream region nearer the body, at high speeds, a wake exists which is similar to the homogeneous wake. At low speeds in this downstream region near the body, the solution shows a pattern of waves decaying in the downstream direction.
Download or read book Philosophical Transactions of the Royal Society of London written by and published by . This book was released on 1989 with total page 750 pages. Available in PDF, EPUB and Kindle. Book excerpt:
