Abdulsattar, Suhaeb S (2014-05). Head Loss Through Fibrous Debris Bed with Different Types of Perforated Strainers. Master's Thesis. Thesis uri icon


  • Safety related issues in Nuclear Power Plants (NPPs) have always been of
    concern, especially those issues that are related to Light Water Reactors (LWRs) and
    their Design Basis Accidents (DBA). One of the ongoing issues that has been
    extensively studied is the Generic Safety Issue GSI-191, which is dedicated to study and
    resolve the issues that arise after a Loss-Of-Coolant-Accident (LOCA). Fibrous debris
    produced during the blow-down phase of Loss-of-Coolant Accidents is transported into
    the sump and becomes an important cause of head loss through the sump strainer,
    affecting the Emergency Core Cooling System (ECCS) performance. This study was
    dedicated to measure the pressure drop across randomly accumulated debris bed on the
    sump strainer along with measuring the debris bed thickness. Two different types of
    strainers were installed vertically, one at a time, in a horizontal flow loop and the debris
    bed thickness was measured during the bed build up process and after reaching steady
    state. Fifteen tests were conducted to determine the head loss difference between the two
    strainers and to study the characteristics of the debris bed accumulated on each strainer.
    The results from this experimental study were compared based on the approaching
    velocity, debris bed thickness, and strainer type. A realistic permeability model for the
    NUKON fiber glass insulation material was suggested, to be utilized in related
    applications, the suggested head loss model was compared to other head loss models
    developed in previous studies. The permeability model was developed from
    experimental data acquired from approaching velocities in the viscous region. There was
    no significant head loss difference between the two strainers for the minimum and intermediate range. Based on the experimental data, the head loss difference between the two strainers for the maximum range was about four times higher than the calculated head loss. The flow rate measurement uncertainty was main reason for the difference in the maximum range. There is a probability that the debris bypass could be different between the two strainers, thus, a debris bypass study is required to further investigate this difference.

publication date

  • May 2014