Fig. 1. Unidirectional and bidirectional fluid-solid coupling

Fig. 2. Structural diagram of the wire-wrapped fuel assembly

Fig. 3. Variation of pressure drop within the fluid domain associated with varying numbers of meshes

Fig. 4. Curve of maximum y⁺ value of wall surface changing with the thickness of the first boundary

Fig. 5. Distributions of Taylor microscale (a) and turbulent energy length scale (b) (color online)

Fig. 6. Time interval curves of pressure for time-step sensitivity analysis (color online)

Fig. 7. Grid independent analysis in solid domain

Fig. 8. Comparison of fluid wall pressure load fluctuations for two turbulence models (color online)

Fig. 9. Comparison of fuel rod vibration for two turbulence models (color online)

Fig. 10. Comparison of results between single and bidirectional fluid-structure interaction methods (color online)

Fig. 11. Comparison of numerical simulation results with UCTD empirical relationships in the fluid domain

Fig. 12. Schematic diagram of the experimental section

Fig. 13. Schematic representation of a turbulent grid

Fig. 14. Comparison of simulation results with experimental results (color online)

Fig. 15. Structural diagram of fuel rod bundle with a wire-wrapped

Fig. 16. Schematic diagram of data extraction points utilized for the analysis of turbulent velocity fluctuations

Fig. 17. Variation of turbulent velocity with time at various monitoring points in the channel 1/2 section (color online)

Fig. 18. Time-domain results of the fluid excitation force acting on the surface of the central fuel rod 1 (color online)(a) Point 1, (b) Point 2, (c) Point 3

Fig. 19. Frequency domain PSD results of the fluid-induced excitation force on the surface of the center fuel rod 1 (color online)(a) Point 1, (b) Point 2, (c) Point 3

Fig. 20. Modal frequencies associated with various states (color online)

Fig. 21. Vibration displacement results in fuel rod 1 at the central position (color online)(a) Total vibration displacement at various positions along the axial direction, (b) Vibration displacement at the axial midpoint

Fig. 22. Vibration displacement results from fuel rod 4 at the peripheral position (color online)(a) Total vibration displacement at various positions along the axial direction, (b) Vibration displacement at the axial midpoint

Fig. 23. Statistical results of vibration displacements at the axial 1/2 position of the fuel rod (color online)(a) Fuel rod 1 at the central position, (b) Fuel rod 4 at the peripheral position

Fig. 24. Frequency domain analysis results of the vibration response at the axial 1/2 position of centre rod 1(a) X-direction, (b) Y-direction

Fig. 25. Frequency domain analysis results of vibration response at the axial 1/2 position of centre rod 4(a) X-direction, (b) Y-direction

Fig. 26. Vibration trajectory at the 1/2 axial position of central rod 1