# DEVELOPMENT OF SECONDARY FLOW AND UNSTEADY SOLUTION THROUGH A CURVED DUCT

#### Authors:

Rabindra Nath Mondal,Md. Sharif Uddin ,Md. Azmol Huda,Anup Kumar Dutta,

#### DOI NO:

https://doi.org/10.26782/jmcms.2008.12.00003

#### Keywords:

Secondary flow,Curved duct,Chaotic flow,Vortex Solution,

#### Abstract

In this paper, development of secondary flow and unsteady by using the spectral method. Numberical calculations are carried out for the Grashof number Gr=1000 over a wide range of the Dean number,0≤Dn≤1000, and the curvature,0<ẟ≤0.5, where the outer well is heated and the inner wall is cooled. First steady solutions are obtained by the Newton-Raphson Iteration method. As a result, we obtain five branches of asymmetric steady solutions with one -two-four-six and eight-vortex Solution at the same Dean number. Then,time evolution calculations of the unsteady solutions are performed, and it is found that the steady flow turns into chaotic flow through periodic flows, no matter with the curvature is Finally, the complete unsteady Solution, covering the wide range of dn and ẟ are shown by a phase diagram.

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Rabindranath Mondal, Md. Sarif Uddin ,Md. Azmol Huda ,Anup Kr. Dutta