Hydro-thermal-mechanical analysis of thermal fatigue in a mixing tee
Titre de la revue : Nuclear Engineering and Design
Volume : 235
N° : 5
Pagination : 575-596
Date de publication : 01/02/2005
This paper covers work carried out by the CEA to study the mechanisms leading to cracking of piping as a result of thermal loading in flow mixing zones. The main goal of the work is to analyse, by calculation, the thermal loading caused by turbulent mixing in tees and to understand the mechanism of initiation and propagation of cracks in such components. This work is supported by IRSN. This thermal fatigue phenomenon is still not fully understood. One of the main obstacles to its understanding resides in the multi-domain nature of the loading and associated damage, involving three complementary scientific disciplines: thermal-hydraulic field, thermo-mechanical field and materials science.
This paper describes the approach adopted by the CEA to establish natural mechanisms (turbulence, pulsing and instability) which might be the cause of any substantial thermo-mechanical loading in the piping.