• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.3
• /
• pp.328-336
• /
• 1998

Marine reduction gears are usually used to increase the propulsion efficiency of propellers for ships powered by medium and small sized high speed diesel engines. Most of shaft systems adopt flexible couplings to absorb the transmitted vibratory torque from the engines to the reduction gears and to prevent the chattering phenomenon of reduction gears. However some elastic couplings show non-linear characteristics due to the variable torque transmitted from the main engines and the change of ambient temperature. In this study dynamic characteristics of flexible couplings sare investigated and their effects upon various vibratory conditions of propulsion systems are clarified. A calculation program of torsional vibration for the propulsion systems are clarified. A calculation program of Results of the program developed are compared with ones of the existing linear method and propulsion systems with the elastic couplings the transfer matrix method is adopted which is found to give satisfied results.

• Journal of Korea Ship Safrty Technology Authority
• /
• v.16
• /
• pp.26-37
• /
• 2004

선박 추진축계의 진동은 크랭크축, 추력축 등의 이상마멸을 초래할 뿐 아니라 과도하면 선체진동을 유발시키기도 한다. 이러한 추진축계의 진동중에서 가장 빈번히 문제가 되는 것이 비틀림 진동이므로 축계의 초기설계 단계부터 이에 대한 신중한 검토가 필요하다 .

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.40 no.3
• /
• pp.232-243
• /
• 2004

After studying the composition about the torsional shafting of main engine for fishing vessel with Power Take Off (PTO) System, the authors made a computer program using the transfer stiffness coefficient method (TSCM) for analyzing torsional vibration about the shafting with PTO system and nonlinear elastic coupling. The torsional shafting of main engine was separated by 3 types according to the connecting. The torsional shafting of main engine was separated by 3 types according to the connecting condition of main engine with propeller or the PTO system or both of them. In this paper, the change of natural frequencies and natural modes according to connecting condition of torsional shafting and nonlinear elastic coupling were analyzed. The accuracy of the TSCM was confirmed by comparing with the computational results of the Finite Element Method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2013.10a
• /
• pp.163-164
• /
• 2013

Two-Way CAR-FERRY land and islands, islands to islands, the connection between sustainable marine transportation in conjunction with the increasing demand of tourists, according to the associated coastal maritime tourism and passenger transport has a role. Subsequent Two-Way CAR-FERRY and the increased ease of use due to berthing maritime accidents can be reduced. Two-Way CAR-FERRY as the draft (even) in the state on both sides of the propeller, because the propeller due to the small diameter, low speed forward flight by the reaction at the shaft and propeller damage can occur. Engine output accordingly, linear and torsional vibration reducer by, elastic coupling selection transverse vibration and shaft alignment (Shaft alignment) considering the shaft design (bearing size, width, thickness) and the primary drive shaft support portion of the hull structure of evaluated for quality.