Thermal–hydraulic performance analysis of a subchannel with square and triangle fuel rod arrangements using the entropy generation approach



The present paper discusses entropy generation in fully developed turbulent flows through a subchannel, arranged in square and triangle arrays. Entropy generation is due to contribution of both heat transfer and pressure drop. Our main objective is to study the effect of key parameters such as spacer grid, fuel rod power distribution, Reynolds number Re, dimensionless heat power ω, length-to-fuel-diameter ratio λ, and pitch-to-diameter ratio ξ on subchannel entropy generation. The analysis explicitly shows the contribution of heat transfer and pressure drop to the total entropy generation. An analytical formulation is introduced to total entropy generation for situations with uniform and sinusoidal rod power distribution. It is concluded that power distribution affects entropy generation. A smoother power profile leads to less entropy generation. The entropy generation of square rod array bundles is more efficient than that of triangular rod arrays, and spacer grids generate more entropy.


Entropy generation Rod bundles Thermal–hydraulics Spacer grids 


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Copyright information

© Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Chinese Nuclear Society, Science Press China and Springer Nature Singapore Pte Ltd. 2017

Authors and Affiliations

  1. 1.Department of Energy Engineering and PhysicsAmirkabir University of TechnologyTehranIran

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