Document Type : Research Note

**Authors**

Department of Mechanical Engineering, Ferdowsi University of Mashhad, Mashhad, P.O. Box 91775-1111, Iran

**Abstract**

The study of the flow and convective heat transfer from rotary sphere in fluid mechanics, astrophysics and astronaut subjects are important. Today, porous mediums use has become widespread because of the heat transfer characteristics as well as their lightweight and low volume. Many numerical studies in heat transfer and fluid mechanics have been done regarding rotary sphere. The present project studies the phenomena of flow and heat transfer due to the rotation of the sphere at a constant temperature around itself in a porous medium, assuming a laminar, steady and incompressible flow. Analytical solution of equations used are based on power series and the porosity coefficient is assumed between 0 to 1in this problem. In the spherical coordinate system used here, changes in azimuthal angle direction are ignored and the body force and pressure gradient for the problem are considered zero. The presence of porous medium is expected to increase thermal parameters.

**Keywords**

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Transactions on Mechanical Engineering (B)

March and April 2022Pages 588-596