Numerical analysis of a heat-generating, truncated conical porous bed in a fluid-filled enclosure. (1st July 2016)

• Record Type: Journal Article
• Authors: Chakravarty, Aranyak; Datta, Priyankan; Ghosh, Koushik; Sen, Swarnendu; Mukhopadhyay, Achintya
• Is Part Of: Energy. Volume 106(2016)
• Page Start: 646
• Page End: 661
• Publication Date: 2016-07-01
• Subjects: Natural convection -- Porous bed -- Heat generating bed -- Truncated cone; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2016.03.103
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: Analysis of natural convection in enclosures containing heat generating porous medium has important applications related to geothermal, chemical, thermal and nuclear energy such as in-vessel cooling of debris beds in nuclear reactors, cooling of coal stockpiles etc. The objective of the present numerical study is to characterise the pattern of fluid flow and energy transfer during steady laminar natural convective flow in a cylindrical enclosure with a centrally placed heat generating porous bed. Flow through porous region is modelled using Darcy–Brinkmann–Forchheimer model and local thermal equilibrium is assumed for the porous region. Analysis is carried out for a wide range of Rayleigh number ( Ra ), Darcy number ( Da ) and thermal conductivity ratio, as well as for different bed geometries. It is observed that in addition to Ra and Da, the bed geometry also plays a very important role in determining flow field and temperature distribution within the enclosure. Interestingly, a significant change is observed in energy transfer mode from the porous bed corresponding to specific values of bed permeability and bed heat generation rate. This is characterised in terms of Ra and Da . Further, it is observed that this change in energy transfer mode is highly dependent on Ra . Highlights: Natural convection is analysed in an enclosure with a heat generating porous bed. Effect of dimensionless parameters as well as bed geometry has been investigated. Energy transfer mechanism from porous bed changes with dimensionless parameters. Bed geometry significantly affects fluid flow and energy transfer in the enclosure.