Analysis of Destruction Laws of Double-Wall Encapsulated Insulation Configuration under LBLOCA Condition

The insulation fiber debris,deduced from the LOCA fluid blasting,is a potential debris source blocking the sump strainer in the containment.The present work simulates the physical process and pressure field of LBLOCA by using of high-pressure air,moreover,destruction law of double-wall encapsulated insulation configuration is analyzed by replaying high speed video and accounting debris.The result indicates that the inner wall is the weakest part for double-wall encapsulated insulation.The modules separated from the pipe due to failure of connection mechanism subjected to high speed air impacting,and the insulation material fragments were released mainly through tearing the inner wall.The stainless-steel bands were proposed to reduce the debris by analyzing the failure mechanism of the insulation configuration.Finally,the insulation improvement method was verified by experiments.