Use of Hydraulic Models in Nuclear Reactor Design

Experimental studies have been conducted on scaled hydraulic models of large pressurized water reactors. Measurements were made of the effect of various internal geometries on the flow distribution at the core inlet and on the Euler numbers. Attention was focused on the relationship between the flow distribution and the length of the flow skirt, the length of the lower plenum and the layout of instrumentation tubes. The design of these components was optimized. Flow distributions in the annuli formed by the thermal shield and in the lower plenum were determined analytically and confirmed experimentally.