The Effects of Local Variation in Thermal Conductivity on Heat Transfer of a Micropolar Fluid Flow Over a Porous Sheet

Subject Areas : Mechanical Engineering

Reza  Keimanesh ¹ (Department of Mechanical Engineering, K. N. Toosi University of Technology, Iran)
Cyrus  Aghanajafi ² (Department of Mechanical Engineering, K. N. Toosi University of Technology, Iran)

Received: 2015-07-12 Accepted : 2017-10-31 Published : 2016-06-01

Keywords: Micropolar fluid, Thermal conductivity, magnetic field, Radiation,

Abstract :

This study is considering a micropolar fluid flow over a porous stretching sheet in the presence of thermal radiation and uniform magnetic field. The effects of local variation in thermal conductivity of micropolar fluid on heat transfer rate from the sheet are investigated; besides, the impacts of radiation, magnetic field and porous sheet on variations of thermal boundary layer thickness are considered. The results show that the increase of thermal conductivity thickens thermal boundary layer, so heat transfer rate decreases. In addition, intensification of magnetic field and the presence of radiation lower the absolute values of temperature gradient on the wall, and reduce the cooling rate of the sheet. On the contrary, the increase of suction and material parameter has positive influence on cooling rate of the sheet.

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