Author: Edmund A. Prych
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 65
Book Description
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.
Turbulent Wakes in Density Stratified Fluids of Finite Extent
Author: Edmund A. Prych
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 65
Book Description
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.
Publisher:
ISBN:
Category : Fluid mechanics
Languages : en
Pages : 65
Book Description
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.
The Growth of a Turbulent Wake in a Density-stratified Fluid
Author: Walter P. M. van de Watering
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 116
Book Description
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).
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 116
Book Description
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).
Report
Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 260
Book Description
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 260
Book Description
Buoyancy Effects in Fluids
Author: John Stewart Turner
Publisher: Cambridge University Press
ISBN: 9780521297264
Category : Mathematics
Languages : en
Pages : 416
Book Description
The phenomena treated in this book all depend on the action of gravity on small density differences in a non-rotating fluid. The author gives a connected account of the various motions which can be driven or influenced by buoyancy forces in a stratified fluid, including internal waves, turbulent shear flows and buoyant convection. This excellent introduction to a rapidly developing field, first published in 1973, can be used as the basis of graduate courses in university departments of meteorology, oceanography and various branches of engineering. This edition is reprinted with corrections, and extra references have been added to allow readers to bring themselves up to date on specific topics. Professor Turner is a physicist with a special interest in laboratory modelling of small-scale geophysical processes. An important feature is the superb illustration of the text with many fine photographs of laboratory experiments and natural phenomena.
Publisher: Cambridge University Press
ISBN: 9780521297264
Category : Mathematics
Languages : en
Pages : 416
Book Description
The phenomena treated in this book all depend on the action of gravity on small density differences in a non-rotating fluid. The author gives a connected account of the various motions which can be driven or influenced by buoyancy forces in a stratified fluid, including internal waves, turbulent shear flows and buoyant convection. This excellent introduction to a rapidly developing field, first published in 1973, can be used as the basis of graduate courses in university departments of meteorology, oceanography and various branches of engineering. This edition is reprinted with corrections, and extra references have been added to allow readers to bring themselves up to date on specific topics. Professor Turner is a physicist with a special interest in laboratory modelling of small-scale geophysical processes. An important feature is the superb illustration of the text with many fine photographs of laboratory experiments and natural phenomena.
The Shape of Two-dimensional Turbulent Wakes in Density-stratified Fluids
Author: Roy Hayden Monroe
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 85
Book Description
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).
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 85
Book Description
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).
Hydraulic Research in the United States
Author:
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 258
Book Description
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 258
Book Description
Experiments on Turbulent Wakes in a Stable Density-stratified Environment
Author: Walter P. M. van de Watering
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 74
Book Description
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).
Publisher:
ISBN:
Category : Turbulence
Languages : en
Pages : 74
Book Description
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).
Current Hydraulic Laboratory Research in the United States
Author:
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 260
Book Description
Publisher:
ISBN:
Category : Hydraulic engineering
Languages : en
Pages : 260
Book Description
NBS Special Publication
Author:
Publisher:
ISBN:
Category : Weights and measures
Languages : en
Pages : 844
Book Description
Publisher:
ISBN:
Category : Weights and measures
Languages : en
Pages : 844
Book Description
Miscellaneous Publication - National Bureau of Standards
Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category : Weights and measures
Languages : en
Pages : 268
Book Description
Publisher:
ISBN:
Category : Weights and measures
Languages : en
Pages : 268
Book Description