Birkhäuser springer apr 2011 (3 risultati)

Taschenbuch. Condizione: Neu. This item is printed on demand - Print on Demand Titel. Neuware -The book contains research results obtained by applying Bejan's Constructal Theory to the study and therefore the optimization of fins, focusing on T-shaped and Y-shaped ones. Heat transfer from finned surfaces is an example of combined heat transfer natural or forced convection on the external parts of the fin, and conducting along the fin. Fin's heat exchange is rather complex, because of variation of both temperature along the fin and convective heat transfer coefficient. Furthermore possible presence of more fins invested by the same fluid flow has to be considered.Classical fin theory tried to reduce the coupled heat transfer problem to a one-dimensional problem by defining an average temperature of the fin and writing equations using this parameter. However, it was shown that this approach cannot be used because of the effects of two-dimensional heat transfer, especially in the presence of short fins. CFD codes offer the possibility to consider bi-dimensional (and more generally, three-dimensional) effects and then a more real approach to the physic phenomena of finned surface's heat exchange.A commercial CFD code was used to analyse the case of heat exchange in presence of T-shaped fins, following an approach suggested by Bejan's Constructal Theory. The comparative results showed a significant agreement with previous research taken as a reference, and this result allows for the application of this approach to a wider range of systems. T-shaped optimized fin geometry is the starting point for further research.Starting from the optimal results (T-shape optimized fins), we show the trend of the assessment parameter (the dimensionless conductance) in function of the angle a between the two horizontal arms of the fin. A value for a, 90°Springer-Verlag KG, Sachsenplatz 4-6, 1201 Wien 220 pp. Englisch.…

Buch. Condizione: Neu. This item is printed on demand - Print on Demand Titel. Neuware -This monograph gives a systematic account of the theory of vector-valued Laplace transforms, ranging from representation theory to Tauberian theorems. In parallel, the theory of linear Cauchy problems and semigroups of operators is developed completely in the spirit of Laplace transforms. Existence and uniqueness, regularity, approximation and above all asymptotic behaviour of solutions are studied. Diverse applications to partial differential equations are given. The book contains an introduction to the Bochner integral and several appendices on background material. It is addressed to students and researchers interested in evolution equations, Laplace and Fourier transforms, and functional analysis. The second edition contains detailed notes on the developments in the last decade. They include, for instance, a new characterization of well-posedness of abstract wave equations in Hilbert space due to M. Crouzeix. Moreover new quantitative results on asymptotic behaviour of Laplace transforms have been added. The references are updated and some errors have been corrected.Springer Nature c/o IBS, Benzstrasse 21, 48619 Heek 552 pp. Englisch.…

Taschenbuch. Condizione: Neu. This item is printed on demand - Print on Demand Titel. Neuware -'Numerische Mathematik', aufgeteilt in zwei Bände, ist eine Einführung in die Numerische Mathematik anhand von Differentialgleichungsproblemen. Gegliedert nach elliptischen, parabolischen und hyperbolischen Differentialgleichungen wird zunächst jeweils die Diskretisierung solcher Probleme besprochen. Als Diskretisierungstechniken stehen Finite-Elemente-Methoden im Raum und (partitionierte) Runge-Kutta-Methoden in der Zeit im Vordergrund. Die diskretisierten Gleichungen dienen als Motivation zur Diskussion von Methoden für endlichdimensionale lineare und nichtlineare Gleichungen, die anschließend als eigenständige Themen behandelt werden. Auf diese Weise wird versucht, nicht nur ein einführendes sondern auch ein in sich abgeschlossenes Bild der Numerischen Mathematik, zumindest in einem zentralen Aufgabenbereich, zu vermitteln.Der zweite Band setzt mit der Diskussion parabolischer und hyperbolischer Anfangsrandwertprobleme fort. Die durch Semi-Diskretisierung im Raum entstehenden Anfangswertprobleme dienen als Einstieg und Motivation der anschließenden Behandlung allgemeiner Anfangswertprobleme gewöhnlicher Differentialgleichungen erster und zweiter Ordnung. Schließlich werden die für diese allgemeinen Problemstellungen erarbeiteten Erkenntnisse auf semi-diskretisierte parabolische und hyperbolische Probleme angewendet.Springer Nature c/o IBS, Benzstrasse 21, 48619 Heek 168 pp. Deutsch.…