Heat flux enhancement by regular surface protrusions in turbulent thermal convection

ORAL

Abstract

We performed two-dimensional numerical simulations in a square Rayleigh-B\'{e}nard (RB) convection enclosure with equally spaced protrusions in the top and bottom conduction plates for the range of Rayleigh number $10^6$ to $10^8$ and at a fixed Prandtl number of $1$. The protrusions are in the form of a parallelepiped base and triangular top with vertex angle $90^o$. We have varied the protrusion height from $10\%$ to $25\%$ of enclosure height and found an increase in heat flux approximately up to $1.38$ times of classical square RB. The enhancement in heat transport up to a certain protrusion height and the heat transport decreases with a further increase in protrusion height. As protrusion height increases, the large-scale circulation can not thoroughly wash out the cavity between two consecutive protrusions.

*We acknowledge the financial support and computational resources provided by the Department of Science and Technology, Government of India through Innovation in Science Pursuit for Inspired Research (INSPIRE), and the Board of Research Nuclear Sciences (BRNS), Department of Atomic Energy, Government of India. We acknowledges the ParamShakti-National Supercomputing Mission for providing their computational resources in IIT Kharagpur.

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Publication: We are planning to submit the paper in Physical Review Fluids

Presenters

  • Prabir K Kar

    • Mechanical Engineering Department, Indian Institute of Technology Kharagpur

Authors

  • Prabir K Kar

    • Mechanical Engineering Department, Indian Institute of Technology Kharagpur

  • Ujjwal Chetan

    • Mechanical Engineering Department, Indian Institute of Technology Kharagpur

  • Jagannath Mahato

    • Mechanical Engineering Department, Indian Institute of Technology Kharagpur

  • Prasanta K Das

    • Mechanical Engineering Department, Indian Institute of Technology Kharagpur
    • Mechanical Engineering Department, Indian Institute of Technology(IIT), Kharagpur
    • Indian Institute of Technology, Kharagpur

  • Rajaram Lakkaraju

    • Mechanical Engineering Department, Indian Institute of Technology Kharagpur