Authors:
Md. Zohurul Islam,Md. Sirajul Islam,Muhammad Minarul Islam,DOI NO:
https://doi.org/10.26782/jmcms.2014.07.00002Keywords:
thermal flow,viscous incompressible fluid ,duct rotation,Taylor number,Grashof number,Abstract
Due to engineering applications and its intricacy, the flow in a rotating curved duct has become one of the most challenging research fields of fluid mechanics. A comprehensive numerical study is presented for the fully developed two-dimensional thermal flow of viscous incompressible fluid through a rotating curved rectangular duct of constant curvature1.0=δ. Numerical calculations are carried out by using a spectral method and covering a wide range of the Taylor number 02000<≤−Trand the Dean number 1000100≤≤Dn for the constant Grashof number100=Gr. A temperature difference is applied, that is the outer wall of the duct is heated while the inner wall is cooled. The rotation of the duct about the center of curvature is imposed, and the effects of rotation (Coriolis force) on the unsteady flow characteristics are investigated. Flow characteristics are investigated for the case of negative duct rotation. We investigate the unsteady flow characteristics for the Taylor number02000<≤−Tr and it is found that the unsteady flow undergoes in the scenario ‘steady-state→ periodic→ multi-periodic → steady-state’, if Tr is increased in the negative direction. Contours of secondary flow patterns and temperature profiles are also obtained at several values of Tr, and it is found that there exist two- and multi-vortex solutions if the duct rotation is involved in the negative direction.Refference:
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Author(s) :Md. Zohurul Islam, Md. Sirajul Islam and Muhammad Minarul Islam View Download