원전 탄소강 배관의 액적충돌침식 손상에 대한 B-Scan 검사 및 수치해석적 분석

• Published in: Corrosion science and technology Vol. 11; no. 6; pp. 218 - 224
• Main Authors: 황경모, Kyeong Mo Hwang, 이대영, Dae Young Lee
• Format: Journal Article
• Language: Korean
• Published: 한국부식방식학회 30.12.2012
• Subjects: flow accelerated corrosion; Liquid droplet impingement erosion; thermal hydraulic analysis; UT inspection; 금속공학; liquid droplet impingement erosion; UT inspection; flow accelerated corrosion; thermal hydraulic analysis
• ISSN: 1598-6462; 2288-6524

Liquid droplet impingement erosion (LDIE) known to be generated in aircraft and turbine blades is recently appcared in nuclear piping. UT thickness measurements with both A-scan and B-scan UT inspection equipments were performed for a component estimated as susceptible to LDIE in feedwater heater vent system. The thickness data measured with B-Scan equipment were compared with those of A-Scan. Thermal hydraulic analysis based on ANSYS FLUENT code was performed to analyze the behavior of liquid droplets inside piping. The wall thinning rate and residual lifetime based on both existing Sanchez-Caldera equation and measuring data were also calculated to identify the applicability of the existing equation to the LDIE management of nuclear piping. Because Sanchez-Caldera equation do not consider the feature of magnetite formed inside piping droplet size colliding frequency the development of new evaluation method urgently needs to manage the pipe wall thinning caused by LDIE.