Modeling and Numerical Analysis of Sphere Packed Beds for cooling a Fusion Reactor Core

Document Type : Research Article

Authors

Department of Mechanical Engineering, University of Shiraz, Shiraz, Iran

Abstract

A vital challenge in fusion nuclear reactors is the heat removal through the embedded channels. Various methods have been employed to improve the reactor core cooling systems. One of the methods in this context is creating turbulence in the flow field by using the sphere packed beds. In the present study, the heat transfers in channels filled with spheres, as a technique to enhance the heat transfer coefficient, is investigated through numerical modelling. The spheres in the channel are assumed as a continuous porous media and domain coefficients are obtained by using the Ergun and the momentum conservation equations. Wall effect in porous media modelling is considered by employing the modified k-ϵ turbulent model. In comparison with the conventional numerical methods that requires high number of unstructured grid generation, the porous media numerical simulation demonstrates acceptable accuracy in obtaining flow field parameters including pressure drop and heat transfer coefficient. Meanwhile, it is concluded that a reduction of porosity results in an increase in pressure drop and heat transfer coefficient.

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