Analysis of Unsteady Fluid Induced Vibration Forces on a Nuclear Fuel Rod Bundle in Turbulent Axial Flow

Author

Abstract

At a nuclear power plants a set of fuel rods held together by spacer grids form a fuel bundle. The coolant flow passing around the rods and the resulting flow turbulence, especially around the spacer grids, exerts transverse, vibrational, and unsteady forces on the rods. The periodic tensions generated by these vibrations will result in fatigue and the reduced mechanical strength of the rods as well as the erosion and the corrosion of the rod clad. In this study, these forces are analyzed in terms of magnitude, amplitude, and intensity of oscillations. To identify the effect of mixing vanes on the spacer grids, simulations were performed for spacer grids both with/without vanes. The obtained results are in good agreement with experimental results. Results showed a 17% increase in pressure drop due to the presence of mixing vanes. The forces exerted to the spacer in the downstream are 10% less than the forces in upstream. Analyses of the fluctuations of the forces applied to the fuel rod bundle showed the amplitude of the vibrations is relatively high at frequencies below 300 Hz.

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1] Pittard, M. T., Evans, T. P., Maynes, R. D. and Blotter, J. D., "Experimental and numerical investigation of turbulent flow induced pipe vibration in fully developed flow", Review of Scientific Instruments", Vol. 75, No. 7, pp. 2393-2401, 2004. [2] Zhang, J., Xu, G., Liu, F., Lian, J. and Yan, X., "Experimental investigation on the flow induced vibration of an equilateral triangle prism in Water", Applied Ocean Research, Vol. 61, pp. 92-100, 2016. [3] Korkischko, I. and Meneghini, J. R., "Experimental investigation of flow-induced vibration on isolated and tandem circular cylinders fitted with strakes", Journal of Fluids and Structures, Vol. 26, No. 4, pp. 611-625, 2010. [4] Franzini, G., Fujarra, A. L. C., Meneghini, J. R., Korkischko, I. and Franciss, R., "Experimental investigation of vortex-induced vibration on rigid, smooth and inclined cylinders", Journal of Fluids and Structures, Vol. 25, No. 4, pp. 742-750, 2009. [5] Assi, G., Meneghini, J., Aranha, J., Bearman, P., Casaprima, E., "Experimental investigation of flow-induced vibration interference between two circular cylinders", Journal of Fluids and Structures, Vol. 22, No. 6, pp. 819-827, 2006. [6] Selvakumar, K. K. and Kumaraswamidhas, L., "Experimental investigation on flow-induced vibration excitation in an elastically mounted circular cylinder in cylinder arrays", Fluid Dynamics Research, Vol. 47, No. 1, pp. 015508, 2015. [7] Shurtz, T., Maynes, D. and Blotter, J., "Analysis of induced vibrations in fully-developed turbulent pipe flow using a coupled LES and FEA approach", in Proceeding of, American Society of Mechanical Engineers, pp. 521-531, 2011. [8] CUI, Z.-d. and GUO, C.-q., "Analysis on critical flow velocities and destabilizing deflection curves of an element model for parallel-plate fuel assembly [J]", Journal of Jinan University (Natural Science & Medicine Edition), Vol. 1, pp. 002, 2005. [9] Kaja, K., Zhao, M., Xiang, Y. and Cheng, L., "Three-dimensional numerical simulations of vortex-induced vibrations of tapered circular cylinders", Applied Ocean Research, Vol. 60, pp. 1-11, 2016. [10] Jiang, X., Andreopoulos, Y., Lee, T. and Wang, Z., "Numerical investigations on the vortex-induced vibration of moving square cylinder by using incompressible lattice Boltzmann method", Computers & Fluids, Vol. 124, pp. 270-277, 2016. [11] Duan, D., Ge, P., Bi, W. and Ji, J., "Numerical investigation on the heat transfer enhancement mechanism of planar elastic tube bundle by flow-induced vibration", International Journal of Thermal Sciences, Vol. 112, pp. 450-459, 2017. [12] مولایی اقدم، الهام، فخار، احمد، نوری بیگدلی، حسین، «شبیه‌‌سازی عددی انتقال حرارت و افت فشار در مبدل حرارتی پوسته و لوله با دستۀ لولۀ بیضوی»، نشریه مهندسی و مدیریت انرژی، جلد 4، شمارۀ 3، صفحه 48ـ59، 1393. [13] Jiadong, Ji., Peiqu, Ge. and Wenbo, Bi, "Numerical analysis of shell-side flow-induced vibration of elastic tube bundle in heat exchanger", Journal of Hydrodynamics, No. 30, pp:1-8, 2018. [14] Vishwanaiadong, K., S. and Balagura, S., "Analysis on Fluid-Induced Vibration and Heat Transfer of Helical Elastic Tube Bundles", Proceedings of ICDMC 2019, pp:621-635,2019. [15] Jiadong, Ji., Unmiao, Gao, Qinghua Chen, Weiqiang Chen and Jingwei, Zhang, "Analysis on Fluid-Induced Vibration and Heat Transfer of Helical Elastic Tube Bundles", Journal of thermophysics and heat transfer, pp:249-257, 2020. [16] Robet, W., Fox, Alan T. McDonald, Philip J. Pritchard and John, W., Mitchell, Introduction to Fluid Mechanics, JOHN WILEY & SONS, INC, 2015 [17] Ganjiani, H., Firoozabadi, B., "Three-dimensional simulation of turbulent flow in 3-sub channels of a VVER-1000 reactor", Scientia Iranica. Transaction B, Mechanical Engineering, Vol. 17, No. 2, pp. 83, 2010. [18] Rehme, K., "The structure of turbulence in rod bundles and the implications on natural mixing between the subchannels", International Journal of Heat and Mass Transfer, Vol. 35, No. 2, pp. 567-581, 1992. [19] Karouta, Z., GU, C.-Y., Schölin, B., 3-D flow analyses for design of nuclear fuel spacer, pp. 1995. [20] عسگری قورتانی، مجید، طالبی، منصور، عبدی، محمدرضا، احمدی‌کیا، حسین، شبیه‌سازی عددی جریان مغشوش اطراف دسته میله‌های سوخت راکتور VVER-440و بررسی اثر نگهدارنده‌ها روی آن»، نوزدهمین همایش سالانۀ مهندسی مکانیک، کد مقاله: ISME19_037 2011.