Abonnement à la biblothèque: Guest
Page d'accueil Archives Thermal Letter Responsables Réunions à venir Assembly for International Heat Transfer Conferences
International Heat Transfer Conference 11

ISSN: 2377-424X (online)
ISSN: 2377-4371 (flashdrive)

TRANSIENT HEAT TRANSFER FROM SINGLE CIRCULAR CYLINDERS AND INLINE TUBE BANKS

G. Jagusch
Corporate Technology Bayer AG D - 51368 Leverkusen Germany

Karl Stephan
Institut fur Technische Thermodynamik und Thermische Verfahrenstechnik, Universitat Stuttgart, Pfaffenwaldring 9, 70550 Stuttgart, Germany

DOI: 10.1615/IHTC11.1820
pages 273-278

Résumé

In the present paper, the fluid flow and heat transfer under transient changes of fluid velocity and thermal boundary conditions are investigated for laminar crossflow over a circular cylinder and a tube bank. Nusselt numbers after step changes of fluid velocity, inlet temperature and wall temperature are calculated by means of a finite element method. The range of Reynolds number investigated is 5 ≤ Re ≤ 200. The fluid is supposed as incompressible with constant properties.
The time responses of Nusselt numbers are approximated by correlations with dimensionless variables. Heat transfer coefficients after step changes of the variables are described as sums of exponential delay functions. The delay times in these correlations are presented as function of the Reynolds number in the range of 5 ≤ Re ≤200.
The calculated heat transfer coefficients agree well with experimental and analytical values of other authors, who studied transient heat transfer at a wire after step changes of the wall temperature and the fluid velocity in a smaller range of Reynolds number 1 ≤ Re ≤ 40. A correlation previously published by others, describing heat transfer after step changes of the wall temperature of a wire for Re = 5 corresponds with our results.

Achat $25.00 Check subscription Déontologie de l'édition scientifique et abus Recommander à mon bibliothécaire Ajouter cette page aux favoris