Sensitivity Tests of Aluminum Precipitate Preparation Methods on Head Loss through Debris Beds on a Sump Screen

摘要

Four head loss tests were conducted in the present study. In the given conditions of debris bed constituents, In-situ Al precipitate resulted in the least additional head loss to the conventional debris bed prepared with NUKON~® and other particulates. Based on the settling tests, faster settling Al precipitate showed greater head loss, which may lead to the conclusion that larger particle size causes more blockage of flow path through a debris bed. In prototypical conditions the additional head loss caused by in-situ prepared Al precipitate would be less than Al precipitate prepared by laboratory protocols such as WCAP-16530. Also, the higher concentration of Al during precipitation would increase the size of the Al particles and pressure drop as a result. In the low approach velocity range of 0.3 to 0.6 mm/s, all the tests resulted in linearly proportional head loss relation to velocity increase. The size of particles from different Al precipitate preparations will be measured in future studies to obtain a quantitative result.