A new profile proposal for the cross sections of the U-tubes of a PWR-SG

The main purpose of this Ph. D. study is to suggest a solution for the problems related to the two-phase flow induced U-tube vibrations of the steam generators, which is one of the most important factors in the design of a PWR. For this purpose, a new type of profile (a symmetrical airfoil) for the cross sections of the U-tubes of the steam generators has been suggested. A comprehensive experimental program, theoretical vibration analysis for the three types of vibration phenomena (fluid-elastic, vortex and turbulent buffeting force induced vibration) and a numerical study have been performed for the suggested profile and the ordinary cylindrical one. (author)