Applying the equations presented in this study for determining fuel element pressure loss as a function of fuel rod bundle hydraulic parameters, it was found that for the required fuel element mass flow rate of 57 lb/sec, fuel element pressure loss is 129 psi + 15%. This is 4.9 psi + 40% above a maximum design value of 80 psi. The corresponding pressure difference across the fuel element liner is 36 psi maximum. Fuel rod spacers are respon¬sible for a large percentage (62%) of the fuel element pressure loss. The following changes can reduce this component by 10, 4 and 24%, respectively.nRemoving one set of spacersnUsing elastic support dimples instead of fingersnDecreasing the thickness of fuel rod spacer material (0.015 ton0.010 in.).
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