RT - Journal Article T1 - Investigation of the Effect of Shroud on Natural Frequencies of a Rotating Multi Blade System JF - mdrsjrns YR - 2019 JO - mdrsjrns VO - 19 IS - 8 UR - http://mme.modares.ac.ir/article-15-17849-en.html SP - 1889 EP - 1896 K1 - Natural Frequency K1 - Multi Blade System K1 - Shroud K1 - Assumed Mode Method AB - In this study, effect of shroud on dynamic characteristics of a rotating multi blade system is investigated. The main aim of this study is to investigate the effect of shroud stiffness and shroud configuration on the system natural frequency. For this purpose, natural frequencies of various systems (in terms of the position, where the blade is connected to the shroud and number of blades, which are connected together with a shroud) via different degrees of shroud stiffness and different configurations of shroud have been compared to show how this parameters affect the natural frequencies of the system. In this study, the shrouds have been considered as the discrete springs with corresponding stiffness values. The vibration frequency characteristics have been analyzed, using assumed mode method along with Hamilton’s law. Since in multi blade systems such as turbines it is crusial to keep the system working frequencies far away from natural frequencies (in order to prevent the resonance phenomenon), based on the results of this paper, it is shown how the parameters of shroud can remove the natural frequencies associated with some of the modes of the system from the work area. LA eng UL http://mme.modares.ac.ir/article-15-17849-en.html M3 ER -