• 한국공작기계학회논문집
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• 제16권3호
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• pp.1-7
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• 2007

Torque fluctuation of an engine and angular velocity variation of a propeller shaft are the main excitation sources in a vehicle driveline. This paper presents the mechanism of these excitation sources. An equivalent model of the engine system and propeller shaft system is constructed to simulate the excitation phenomena. The analytical model contains the geometrical and dynamic mechanism. Combustion pressure of the cylinder is measured from dynamometer. The computer simulation is carried out by commercial program package. Results of the simulations show the characteristics of the torsional excitation source of the driveline.

• 한국소음진동공학회논문집
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• 제15권7호
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• pp.865-870
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• 2005

Torque fluctuation of the engine and angular velocity variation of propeller shaft is the main excitation source for torsional vibration in the vehicle driveline. Experimental model for engine system is constructed with 4 cylinder 4 cycle diesel engine including Motor-Propeller Shaft-Axle-Wheel system. The angular velocity is measured by magnetic pickup and FV converter at the engine flywheel and propeller shaft. This paper presents the theoretical mechanism of these excitation sources and it is identified by the experimental methods.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.925-930
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• 2004

This paper is to study vibration effects of the dynamic vibration absorber. Multi-body dynamic analysis is carried out for the vehicle driveline model using ADAMS with flexible propeller shaft attached with the vibration damper. Primary bending mode frequency of the propeller shaft is obtained from the simulation and coincides with the experimental result. Various design parameters are studied in dynamic simulation operated by the engine torque input. This paper identifies the responses of dynamic vibration absorbers in the driveline with propeller shaft, which will be used to find out optimal design parameters.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
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• pp.173-179
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• 2001

The torsional or axial critical vibration of the order coinciding with the number of propeller blades is simultaneously excited by the harmonic tangential or radial forces acting on the crank shaft and by the harmonic of the same order from the propeller. The exciting torque of propeller is relatively small comparing with that of crank side, but the exciting force of propeller rather larger than that of crank shaft. With this situation, the exciting force of propeller cannot neglect if the axial vibration of propulsion shafting is calculated. With the propeller in its optimal angular position, i.e. its excitation effect opposed to that of the engine, the stresses at the critical revolution will largely cancel themselves out. In this paper, a method of optimizing the angular propeller position with regard to torsional and axial vibration is studied. The optimal relative angle is determined theoretically by calculation results of coupled torsional-axial vibration.

• 대한조선학회논문집
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• 제58권1호
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• pp.40-48
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• 2021

Through a series of bollard pull tests of a propeller in partially submerged condition, thrust, torque, and shaft excitation force of a conventional propeller model were measured using a six-component load cell. By variation of the Weber number and Reynolds number, a consistent towing tank model test condition was derived. The effects of propeller immersion depth on the ventilation behavior and change of force and moment acting onto the propeller shaft were investigated. The decrease in thrust owing to the inception of ventilation was confirmed, and a large degree of dispersion of the thrust and torque coefficients were also observed in the transition region where the blade tip was under the water surface. The shaft excitation force was derived from the force and moment onto the propeller shaft.

• 대한조선학회논문집
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• 제34권1호
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• pp.50-59
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• 1997

선박의 시운전 수행 이전에 엔진 및 프로펠러의 작동상태를 체크하기 위하여 때때로 안벽계류 중에서 주기 및 발전기의 성능시험을 수행하는 데, 이때 주기관을 100% 작동시키는 것은 계류용 로프 및 안벽 비트의 강도 문제등의 여러가지 위험 부담을 갖게 된다. 본 연구는 이러한 시험에 대한 안전성 검토를 위해 필요한 프로펠러의 추력의 추정을 목적으로 하고 있다. 대상선은 최근에 건조한 대형 컨테이너선이며, 실선시험은 안벽계류 상태에서 수행되었기 때문에 프로펠러는 수면위로 노출되어 있는 상태에서 작동되었다. 이러한 낮은 프로펠러 축 몰수 수심에서 작동하는 안벽계류 상태에서의 프로펠러의 특성을 조사하기 위해 모형시험을 수행하였으며, 이들 시험결과로부터 안벽계류 시험중의 프로펠러의 추력에 관한 약산식이 도출되었다. 그 결과 프로펠러의 특성은 축 수심에 따라 크게 달라지는 것을 알 수 있으며, 특히 축 수심이 작아 프로펠러가 수면위에 노출되어 있는 경우에는, 같은 축 수성에서도 프로펠러 회전수에 지배되는 특성이 파악되었다. 한편 심수 중에서 작동하는 프로펠러에 대해서도 추력에 대한 추정식을 도출하여 실선 시험 담당자가 사용하기 쉽게 하였으며, bollard pull에서의 FPSO(Floating Production Storage and Offloading tanker based system) 의 프로펠러의 추력 계측값과 비교 검토 하였다.

• 한국해양공학회지
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• 제12권1호
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• pp.23-31
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• 1998

Kind 1 propeller shaft in ships is the shaft which is provided with effective measures against corrosion by sea water, or the shaft which is made of approved corrosion resistance materials. The propeller shaft other than specified above is Kind 2. Thus, this study is mainly concerned with the resistance to fatigue damage in sea water against stress concentrations due to the notches. The results obtained can be summarized as follows; (1) The stress increases with curing time, however, when the curing time reaches at 96 hours the stress becomes a constant value. The elongation decreases with curing time, however, when the curing time reaches at 48 hours the elongation becomes a constant value. Thus, in case of FRP coating on propeller shaft, it is necessary to cure for 48 hours at least. (2) The relation of $\sigma$$_n$-K$_t$ is to be classified into two parts, which is a part where fracture nominal stress, $\sigma$$_n$, decreases with increasing $K_t$, and a part where $\sigma$$_n$ is nearly constant independent of $K_t$. (3) According to a linear notch mechanics, the measure of severity controlling the fracture in notched FRP body is the notch root radius, $\rho$. The notched static strength of an arbitrary specimen will be estimated from $\sigma$$_{max}$ -1/$\rho$ curve. (4) Through the observation of cross section after fatigue test, the part of interface was kept good condition irrespective of loading conditions.

• 해양환경안전학회지
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• 제26권4호
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• pp.412-418
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• 2020

선박 축계를 구성하는 프로펠러축은 엔진출력, 프로펠러 하중 및 편심추력의 영향으로 인해 거동의 양상이 달라져 선미관 후부베어링의 국부하중 변화를 일으킴으로써 선미관 베어링 손상의 위험을 증가시킨다. 이를 방지하기 위해 수행된 추진축계 정렬연구는 선급강선규칙을 중심으로 주로 축과 지지베어링간의 상대적 경사각과 유막유지를 최적화 하는데 중점을 두어 진행 되어왔다. 그러나 보다 상세한 평가를 통한 추진축계의 안정성 확보를 위해서는 전타와 같은 급격한 선미유동장 변화에 기인한 과도상태를 포함한 동적상태의 고려가 필요하다. 이러한 관점에서, 본 연구는 50,000 DWT 선박을 대상으로 스트레인 게이지법을 이용하여 밸러스트 흘수 상태에서 정격회전수로 운전 중 대표적 동적 과도상태인 우현 전타상태에서의 프로펠러 축 거동이 추진축계에 미치는 영향을 분석하였다. 그 결과 변동된 프로펠러 편심추력은 프로펠러축을 일시적으로 강하게 내려 누르는 힘으로 작용하여 선미관 베어링의 국부하중을 증가시켜 축계 안정성에 부정적 영향을 미침을 증명하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.99-104
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• 2008

The Carbon fiber epoxy composite material and aluminum have many advantages about higher specific stiffness and good fatigue characteristics. basically, the propeller shaft of automobile must satisfy high natural frequency more than 9,200 rpm to satisfy high number of rotation and high torsion torque more than 2,700Nm. In these reason, studied natural frequency and torsion torque characteristics of shaft according to parameter variations with the outdiameter and thickness. From the torsion tester and natural frequency experiments FE analyses was compared vibration and torque characteristics of hybrid shaft Designed hybrid shaft was experimented through FFT analyzer and torsion tester each and satisfied that hybrid shaft reverence 60mm and thickness 5mm by a these experiment is most suitable. Therefore, that can manufacture existent steel two piece type propeller shaft to one piece type hybrid shaft.

• Journal of Advanced Marine Engineering and Technology
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• 제2권1호
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• pp.3-14
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• 1978

The authors have developed a calculating method of propeller shaft alignment by the finite element method. The propeller shaft is divided into finite elements which can be treated as uniform section bars. For each element, the nodal point equation is derived from the stiffness matrix, the external force vector and the section force vector. Then the overall nodal point equation is derived from the element nodal point equation. The deflection, offset, bending moment and shearing force of each nodal point are calculated from the overall nodal point equation by the digital computer. Reactions and deflections of supporting points of straight shaft are calculated and also the reaction influence number is derived. With the reaction influence number the optimum alignment condition that satisfies all conditions is calculated by the simplex method of linear programming. All results of calculation are compared with those of Det norske Veritas, which has developed a computor program based on the three-moment theorem of the strength of materials. The authors finite element method has shown good results and will be used effectively to design the propeller shaft alignment.