Heat transfer experiment in a partially (internally) blocked 19-rod bundle with wire spacers cooled by LBE

The experimental results are presented following two approaches. First, selected reference cases are described in detail, allowing for a direct comparison with numerical simulations. Second, the results for all cases are correlated in dimensionless terms. An empirical model named Karlsruhe Blockage Equation (KBE) is proposed for representing the heat transfer resistance at the hottest spots in the blocked region for each element. Extrapolating these results to full-power conditions, the temperature increase produced by solid blockages with low thermal conductivity can be acceptable if they are small and excessive if they are larger. Further results include the wall and fluid temperature in the wake region and differential pressure in blocked and unblocked sections of the bundle.