Skip to main content
main-content

Über dieses Buch

The book is devoted to investigation of a series of problems of convective heat and mass transfer in rotating-disk systems. Such systems are widespread in scienti?c and engineering applications. As examples from the practical area, one can mention gas turbine and computer engineering, disk brakes of automobiles, rotating-disk air cleaners, systems of microclimate, extractors, dispensers of liquids, evaporators, c- cular saws, medical equipment, food process engineering, etc. Among the scienti?c applications, it is necessary to point out rotating-disk electrodes used for experim- tal determination of the diffusion coef?cient in electrolytes. The system consisting of a ?xed disk and a rotating cone that touches the disk by its vertex is widely used for measurement of the viscosity coef?cient of liquids. For time being, large volume of experimental and computational data on par- eters of ?uid ?ow, heat and mass transfer in different types of rotating-disk systems have been accumulated, and different theoretical approaches to their simulation have been developed. This obviously causes a need of systematization and generalization of these data in a book form.

Inhaltsverzeichnis

Frontmatter

Chapter 1. General Characteristic of Rotating-Disk Systems

Rotating-disk systems are widely used in gas turbine engineering, aircraft engines, computer disk drives, car breaks systems, rotational air cleaners, extractors, atomisers, evaporators, microclimate systems, chemical engineering, electrochemistry, medical equipment, food processing technologies, etc. Widely spread are the cases of disk rotation in an infinite resting fluid or fluid rotating with another angular velocity
Igor V. Shevchuk

Chapter 2. Modelling of Fluid Flow and Heat Transfer in Rotating-Disk Systems

We will consider here stationary axisymmetric fluid flow over disks rotating with a sufficiently high angular velocity so that effects of gravitational forces on momentum transfer are rather low. In a stationary cylindrical coordinate system arranged in such a way that a disk or a system of disks rotate around its axis of symmetry coinciding with the axis
Igor V. Shevchuk

Chapter 3. Free Rotating Disk

A schematic of fluid flow and convective heat transfer over a free rotating disk in infinite ambience is depicted in Fig. 3.1. Velocity and temperature profiles computed numerically based on a solution of the self-similar system of Eqs. (2.37), (2.38), (2.39), (2.40) and (2.41) for β=0, N=0 with the help of the MathCAD software are presented in Fig. 3.2.
Igor V. Shevchuk

Chapter 4. Unsteady Laminar Heat Transfer of a Free Rotating Disk

Transient heat transfer investigations are a matter of great importance both from the fundamental and applied points of view, primarily, in turbomachinery. One of the most widely used applications comprises various transient experimental techniques of determining surface heat transfer of a body in stationary hydrodynamic conditions. Such techniques, currently employing thermochromic liquid crystals, are based on the known fact that after a certain period of time from the beginning of the cooling process, the surface heat transfer coefficient becomes a time-independent function equal to its value for steady-state heat transfer under the same boundary conditions. The heat flux in this situation can be computed from more or less simple analytical solutions for unsteady heat conduction inside solid bodies for known surface temperatures. Experimentally measured dependencies of the surface temperature on time are substituted into the mentioned analytical solutions, and the resultant algebraic equations are further solved to find the heat transfer coefficients [91, 112, 121, 154–156, 176, 215].
Igor V. Shevchuk

Chapter 5. External Flow Imposed over a Rotating Disk

Geometrical arrangements with disks rotating with an angular velocity ω in a fluid, which rotates in the same direction with a velocity Ω different from ω, may be found in many technical applications such as parallel disks co-rotating with different angular velocities, disks rotating in swirling flows, etc. [114, 138, 139, 196]. If ω>Ω (or β=vϕ,∞/(ωr)<1), then fluid flow on the disk surface caused by rotation is radially outward (centrifugal). A schematic diagram of such flow is outlined in Fig. 5.1. Physically, flow for β<1 looks like flow over a free disk for β=0, with quantitative relations for the velocity and temperature fields being dependent on a particular non-zero value of β.
Igor V. Shevchuk

Chapter 6. Outward Underswirled and Overswirled Radial Flow Between Parallel Co-rotating Disks

This section overviews in brief the model and results for the Ekman layers, which are important for understanding and simulations of the flow regimes that develop in rotating-disk cavities.
Igor V. Shevchuk

Chapter 7. Laminar Fluid Flow and Heat Transfer in a Gap Between a Disk and a Cone that Touches the Disk with Its Apex

Conical diffusers with stationary walls are known in engineering . For modelling fluid flow in such devices, with flow swirl at the inlet being absent, simplified Navier Stokes equations were used in while heat transfer has never been simulated in any of the known investigations.
Igor V. Shevchuk

Chapter 8. Heat and Mass Transfer of a Free Rotating Disk for the Prandtl and Schmidt Numbers Larger than Unity

Problems of heat and mass transfer in fluid flow over a rotating disk for the Prandtl or Schmidt numbers larger than unity are of great importance in a number of industrial and scientific applications. To mention a few, one should count electrochemistry, where the rotating-disk electrode technique is widely used for experimental determination of the diffusion coefficient at the Schmidt numbers much larger than unity [3, 6, 8, 37, 39, 40, 42, 48, 81, 102, 105, 126, 131, 157]. The second area of application actual for the present research is the naphthalene sublimation technique often employed in experimental measurements of the mass transfer coefficients h m [24, 28, 29, 59, 64, 96, 97, 117, 193, 195, 201, 208].
Igor V. Shevchuk

Backmatter

Weitere Informationen

Premium Partner

BranchenIndex Online

Die B2B-Firmensuche für Industrie und Wirtschaft: Kostenfrei in Firmenprofilen nach Lieferanten, Herstellern, Dienstleistern und Händlern recherchieren.

Whitepaper

- ANZEIGE -

Grundlagen zu 3D-Druck, Produktionssystemen und Lean Production

Lesen Sie in diesem ausgewählten Buchkapitel alles über den 3D-Druck im Hinblick auf Begriffe, Funktionsweise, Anwendungsbereiche sowie Nutzen und Grenzen additiver Fertigungsverfahren. Eigenschaften eines schlanken Produktionssystems sowie der Aspekt der „Schlankheit“ werden ebenso beleuchtet wie die Prinzipien und Methoden der Lean Production.
Jetzt gratis downloaden!

Marktübersichten

Die im Laufe eines Jahres in der „adhäsion“ veröffentlichten Marktübersichten helfen Anwendern verschiedenster Branchen, sich einen gezielten Überblick über Lieferantenangebote zu verschaffen. 

Bildnachweise