Numerical Analysis of Flow and Heat Transfer for Semi Spheres Placed As Multiple Serials In a Channel

Abstract

Excessive heating of electronic equipments may cause both decreasing thermal performance of system and undesirable consequences such as increased thermal stresses and mechanical defects in the system. In the literature, there are many studies including applications of thermal analysis and technologies in order to make cooling more effective. In this study, flow and heat transfer are investigated numerically in the case of three dimensional, incompressible, fully developed and laminar flow for semi spheres placed as multiple serials in a channel. The continuity, Navier-Stokes and energy equations are solved numerically by using  Ansys Fluent-17.0 software program. Air is taken as working fluid. Inlet temperature of the air and sphere surface temperatures are 300 K and 350 K, respectively. The effects of location of semi spheres as multiple serials, placement angle and positions of sphres according to each other on the pressure drop and heat transfer enhancement for case of different Re numbers (Re=100, 200, 400 ve 800) are researched. The obtained results show that the positions of spheres have a great importance in the case of placement as multiple serials of semi spheres.

Keywords

• Semi sphere,converging and diverging channels,heat transfer

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