The study of the vibration of the floating structure due to the excitation of the propeller using numerical analysis of fluid-structure (FSI)

Subject Areas : Vibration Transmision

Mahdiesadat Azizai ¹ , Yousef Amirian ² , Abdolhossein Fereidoon ³

1 - Department of Mechanical Engineering, Semnan Branch, Islamic Azad University, Semnan, Iran
2 - Department of Marine Technology Engineering, AmirkabirUniversity of Technology, Tehran, Iran
3 - Department of Mechanical Engineering, SemnanUniversity, Semnan, Iran

Received: 2015-08-26 Accepted : 2015-08-26 Published : 2011-08-23

Keywords: Structural analysis, Forced vibration, structure, Modal Analysis, angular velocity of the propeller,

Abstract :

Vibration of floating structures under the effect of propeller excitation is One of the main issues in the design of floating structures and not paying attention to this issue and the placement Super structure at the bottom of the float, vibrations caused by the stimulus of the fan can cause problems for crews and individuals and the vibrations from the propeller make noise and also reduce the life of existing machines in the bottom of the float. In this paper the vibrations caused by the propeller stimulation, using a numerical analysis of fluid-structure on a commercial vessel is studied and the results are discussed. First with respect to the geometry and condition a suitable propeller was chosen for the float and the numerical solution for different speeds of the float and the angular velocity of the impeller is done. The floating structure is designed based on the standard and discretization is conducted using finite element.  Pressure distribution on the propeller and hull obtained from the numerical solution of fluid flow, has been applied to floating structures in the structural analysis and floating structures due to harmonic loading induced by the rotation of the propeller is investigated and modal analysis of floating structures has been performed And the results of its analysis in a frequency range including natural frequencies that canaries in different modes and rotational speeds  of the propeller were recorded. The Results show that in some rotational speeds of the propeller excitation frequency in rotational speed can lead to vibration increase and resonance amplitude The results are compared with the standard range, the results show that with accurate choosing of the propeller And the range of allowable angular velocity and optimization of the structure, we can provide the Requirements for vibration exposure in the limited range.