Abstract
In this research, the free vibration analysis of cylindrical shells with circumferential stiffeners, i.e., rings with nonuniform stiffener eccentricity and unequal stiffener spacing, is investigated using analytical and experimental methods. The Ritz method is applied in analytical solution, while stiffeners are treated as discrete elements. The polynomial functions are used for Ritz functions. The effects of nonuniformity of stiffener distribution on natural frequencies are considered for free–free boundary conditions. Results show that, at constant stiffener mass, significant increments in natural frequencies can be achieved using nonuniform stiffener distribution. In experimental method, modal testing is performed to obtain modal parameters, including natural frequencies, mode shapes, and damping in each mode. Analytical results are compared with experimental ones, showing good agreement. Because of insufficient experimental modal data for nonuniform stiffener distribution, the results of modal testing obtained in this study could be a useful reference for validating the accuracy of other analytical and numerical methods for free vibration analysis.
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AL-Najafi, A.M.J., Warburton, G.B.: Free vibration of ring stiffened cylindrical shells. J Sound Vib 13(1), 9–25 (1970)
Egle, D.M., Sewall, J.L.: Analysis of free vibration of orthogonally stiffened cylindrical shells with stiffeners treated as discrete elements. AIAA J 6(3), 518–526 (1968)
Hoppmann, W.H.: Some characteristics of the flexural vibrations of orthogonally stiffened cylindrical shells. J Acoust Soc Am 30, 77–82 (1958)
Mikulas, M.M., McElman, J.A.: On the free vibration of eccentrically stiffened cylindrical shells and plates. NASA TN-D 3010 (1965)
Mustafa, B.A.J., Ali, R.: An energy method for free vibration analysis of stiffened circular cylindrical shells. Comput Struct 32(2), 335–363 (1989)
Rosen, A., Singer, J.: Vibrations of axially loaded stiffened cylindrical shells. J Sound Vib 34(3), 357–378 (1974)
Ruotolo, R.: A comparison of some thin shell theories used for the dynamic analysis of stiffened cylinders. J Sound Vib 243(5), 847–860 (2001)
Sanders, J.L.: An improved first-approximation theory for thin shells. NASA TR R-24 (1959)
Swaddiwudhipong, S., Tian, J., Wang, C.M.: Vibrations of cylindrical shells with intermediate supports. J Sound Vib 187(1), 69–93 (1995)
Wang, C.M., Swaddiwudhipong, S., Tian, J.: Ritz method for vibration analysis of cylindrical shells with ring stiffeners. J Eng Mech 123, 134–142 (1997)
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Bagheri, M., Jafari, A. Analytical and experimental modal analysis of nonuniformly ring-stiffened cylindrical shells. Arch Appl Mech 75, 177–191 (2006). https://doi.org/10.1007/s00419-005-0429-y
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DOI: https://doi.org/10.1007/s00419-005-0429-y