Journal of Vibration and Sound

Journal of Vibration and Sound

A numerical study of ship motions effects on the static and vibration characteristics of the tower

Document Type : research article

Authors
Hamidreza Rostami 1
Vahdat Pirouzram 2
Firooz Bakhtiari-Nejad 3
Javad Orooji 1
1 Department of Ocean Engineering, Amirkabir University of Technology, Tehran, Iran.
2 Department of Mechanical Engineering, Malek-Ashtar University of Technology, Tehran, Iran
3 Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, Iran.
Abstract
The static and vibration studies of a tower of a surface float is investigated in this paper. Designing a ship's telecommunication tower is one of the most important issues in designing the ship from the structural point of view to install the required types of antennas and radars. Therefore, in the analysis, the telecommunication tower and the deck of the ship are modeled. After examining the static state and calculating deformations and stresses, according to the ship's movements, the resulting forces are added to the analysis and the effects on the stresses and displacements are obtained. It should be noted that in this analysis, accelerations as gravitational force, rotational accelerations as rotational volume forces, and also radar weight as a concentrated force are applied to the structure. Next, frequency analysis is performed and different structural modes are extracted. The results show that in the design process, in addition to considering the parameters of tower design (such as boundary conditions, operating load, places of members), their location of using should also be considered. The use of towers on the deck of the vessels significantly reduced the safety factor. Also, it can be observed various phenomena such as fatigue in the limbs, especially the connection place to the deck, which can have very destructive effects in the long run and reduce the life of the structure. Therefore, in designing the towers of floating structures, more safety factors should be considered and special attention should be paid to the movements of the vessel.
Keywords
Tower
Telecommunication tower
Ship motions
Static analysis
Vibration analysis
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Journal of Vibration and Sound
Volume 9, Issue 17 - Serial Number 17
September 2020
Pages 39-54