Transient natural convection in partitioned enclosures

• Autorzy: Zemani F. , Sabeur-Bendehina A.
• Języki publikacji: EN

Abstrakty

EN

In this paper, the natural convection flow in a cavity heated differentially with a partition placed in the middle of the hot wall is numerically simulated. The aspect ratio of the geometry, Prandtl number are fixed at 0.24, 6.64, respectively, for different partitions lengths; however the Rayleigh number values were ranging from 10⁶ to 3:77 x 10⁹ in order to observe the transition regime. The fluid flow and the heat transfer described in terms of continuity, linear momentum and energy equations were predicted by using the finite volume method. To approach the physical reality experience, calculations were performed in a cavity with the same size and same priority of the fluid with an average temperature Tm imposed on the cooled wall, also another simulation with an average temperature Tm imposed on the horizontal wall. Time evolution, isotherms and mean Nusselt number are presented for all investigated values. Representative results illustrating the effects of the partition length for the heat transfer and the thermal boundary layer are also reported and discussed. The results indicate that the flow and heat transfer properties are altered by the presence of the partition, especially in the initial stage. In a certain sense, the partition blocks the flow and forces it to come off the hot wall. Since the partition parameters are critical for the transient natural convection ow in the cavity, different partition lengths on the warm wall have been studied.

Słowa kluczowe

EN

natural convection; transient regime; partial partitions; Rayleigh number; Nusselt number; partitions length

PL

konwekcja naturalna; reżim nieustalony; przegroda częściowa; liczba Rayleigha; liczba Nusselta; długość przegrody

• Wydawca: Wydawnictwo Politechniki Łódzkiej
• Czasopismo: Mechanics and Mechanical Engineering
• Rocznik: 2018
• Tom: Vol. 22, nr 4
• Strony: 1015--1030
• Opis fizyczny: Bibliogr. 25 poz., il. kolor., rys., wykr.

Twórcy

autor

Zemani F.

• Laboratoire des Sciences et Ingénierie Maritimes, Faculté de Génie Mécanique, Université des Sciences et de la Technologie d'Oran Mohamed Boudiaf Oran, B.P. 1505 Oran El-M'naouar, 31000 Oran, Algérie

autor

Sabeur-Bendehina A.

• Laboratoire des Sciences et Ingénierie Maritimes, Faculté de Génie Mécanique, Université des Sciences et de la Technologie d'Oran Mohamed Boudiaf Oran, B.P. 1505 Oran El-M'naouar, 31000 Oran, Algérie

Bibliografia

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Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).