Isogeometric analysis for flow-induced vibration of U tubes in steam generators

This paper presents the first reference on the use of the isogeometric analysis (IGA) for flow-induced vibration (FIV) of steam generator U tubes in pressurized water reactors (PWR). It describes in detail the IGA implementation of the recently proposed semi-analytical time-domain (SATD) model for tube bundles in cross-flow, offering an alternative option to the traditional finite element method (FEM) predominating in the field. Much fewer elements required for spatial discretization, faster convergence, and higher order of smoothness of solution, make IGA an ideal method for FIV of U tubes. A benchmark experiment reported in literature is chosen as the numerical example and a detailed study is performed for both linear and nonlinear dynamic response analysis. Good agreement is achieved between IGA prediction and reported experimental data. The method opens a new avenue for FIV of curved tubes, pipes, and cylinders with complicated forces and boundary conditions. • First use of IGA for flow-induced vibration analysis of steam generator U tubes. • IGA achieves faster convergence and fewer elements than traditional FEM. • Experimental validation confirms high accuracy of IGA predictions. • IGA enables nonlinear dynamics analysis for curved beams and complex supports.