Research Study on Fluidelastic Instability in Nuclear Steam Generators

Canada is seeking offers from qualified Offerors to provide professional services to deliver the “Enhanced understanding of fluidelastic instability (FEI) in nuclear steam generators, specifically in the streamwise (in-line) direction, to ensure the long-term reliability and structural integrity of tube arrays under two-phase flow conditions” study to Canadian Nuclear Safety Commission.

The scope of this study includes the following three interrelated components: • Establishing a test setup to facilitate observation and assessment of local void fraction behavior and flow-induced responses in tube arrays representative of CANDU steam generators.

The setup is based on established configurations and industry knowledge, with the goal of supporting technical evaluation under controlled two-phase flow conditions. • Execution of flow assessments using multiple test sections with representative pitch ratios.

Tests are conducted across a range of flow conditions (approximately 50 to 500 kg/m²·s mass flux) to capture relevant stability behavior under typical operating parameters. • Data collection and technical analysis to generate a structured dataset that can support future studies and inform regulatory assessments.

The results contribute to an improved understanding of how tube arrays respond under various conditions, particularly regarding the onset and behavior of streamwise fluidelastic effects.