Sea trial researches on extraction of propeller shaft frequency

The cone valve plays an important role in high-pressure sealing applications. In this paper, a new high-pressure cone valve, based on the titanium alloy poppet-to-polyetheretherketone seat sealing structure, is proposed for deep-sea gas-tight water samplers. In order to study the sealing performance of the new valve, both the conforming poppet-seat contact model and the nonconforming poppet-seat contact model were evaluated. Finite element analysis based on the two models was performed and validated by experiments. The results indicate that the nonconforming poppet-seat contact model has a better sealing performance than the conforming poppet-seat contact model. The new cone valve also was applied in a gas-tight hydrothermal fluid sampler and successfully tested in a sea trial during the KNOX18RR cruise from 9 July to 12 August 2008.

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Vibration and sound radiation analysis of the final drive assembly considering the gear-shaft coupling dynamics

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406216632021 ◽

2016 ◽

Vol 230 (7-8) ◽

pp. 1258-1275 ◽

Cited By ~ 9

Author(s):

Yawen Wang ◽

Junyi Yang ◽

Dong Guo ◽

Teik C Lim

Keyword(s):

Dynamic Models ◽

Acoustic Analysis ◽

Bending Moment ◽

Moment Of Inertia ◽

System Dynamic ◽

Dynamic Responses ◽

Propeller Shaft ◽

Hypoid Gear ◽

Gyroscopic Effect ◽

Gear Mesh

A generalized dynamic model of driveline system is formulated that includes the coupling effect and gyroscopic moments of the propeller shaft and hypoid gear rotor assembly. Firstly, the dynamic models with only gear-shaft coupling, with only gyroscopic effect, and with both gear-shaft coupling and gyroscopic effect are analyzed and compared. The results show that the combined effects of the gear-shaft interaction and gyroscopic behavior have considerable influence on the system dynamic responses surrounding gear bending resonances, especially for the bearing responses. However, the gear out-of-phase torsional modes still dominate the gear mesh frequency response. Secondly, the influence of pinion bending moment of inertia, propeller shaft stiffness and bearing stiffness on the system dynamic responses are examined. The system responses are then applied to perform further vibration and acoustic analysis for an axle housing structure. Computational results reveal that NVH (noise, vibration, and harshness) refinement can be achieved by tuning the pinion bearing rotational stiffness and pinion bending moment of inertia for the example considered. This study provides an understanding of the interaction between hypoid gear pair and propeller shaft, and can be employed to enhance driveline system design.

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Economical Aspects of Cutting Speed Selection When Turning Stepped Parts

Journal of Engineering for Industry ◽

10.1115/1.3428050 ◽

1971 ◽

Vol 93 (4) ◽

pp. 1113-1119 ◽

Cited By ~ 1

Author(s):

L. Kops

Keyword(s):

Cutting Speed ◽

Minimum Cost ◽

Turbine Disk ◽

Constant Speed ◽

Graphical Form ◽

Propeller Shaft ◽

Analytical Comparison ◽

Speed Selection ◽

Time Required ◽

Speed Method

The concept is developed of analytical comparison between two methods of cutting speed selection when cutting stepped parts: the constant rpm method and constant cutting speed method. Formulas for cost and time of machining stepped parts are derived and analyzed for two different examples of stepped parts: short ones with large differences in diameters (turbine disk) and long ones with small differences in diameters (propeller shaft). The results presented in graphical form show the advisable operating regions for the use of one of the two methods considered. The effect of time required to change the rpm on the effectiveness of the constant speed method is examined and the limit of applicability is determined. It is found that a reduction of as much as 1/3 in cost and time may be obtained when the constant speed method is applied in the case of the turbine disk. It is noted also that the minimum-cost speed and minimum-time speed depend on the choice of the method and on the shape of the machined part as well. The conclusions set out the conditions under which the use of the constant cutting speed method is justified.

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Sonar watermark embedding and detection: a sea trial report

10.1117/12.920842 ◽

2012 ◽

Author(s):

Bijan G. Mobasseri ◽

Nagarjun Chakilam ◽

Robert S. Lynch

Keyword(s):

Trial Report ◽

Sea Trial ◽

Watermark Embedding

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The Estimation of Angular Misalignments for Ultra Short Baseline Navigation Systems. Part II: Experimental Results

Journal of Navigation ◽

10.1017/s0373463313000234 ◽

2013 ◽

Vol 66 (5) ◽

pp. 773-787 ◽

Cited By ~ 7

Author(s):

Hsin-Hung Chen

Keyword(s):

Trial Data ◽

Experimental Results ◽

Experimental Result ◽

Alignment Error ◽

Navigation Systems ◽

Analytical Prediction ◽

Short Baseline ◽

Sea Trial ◽

Alignment Errors ◽

Cross Track

An algorithm of alignment calibration for Ultra Short Baseline (USBL) navigation systems was presented in the companion work (Part I). In this part (Part II) of the paper, this algorithm is tested on the sea trial data collected from USBL line surveys. In particular, the solutions to two practical problems referred to as heading deviation and cross-track error in the USBL line survey are presented. A field experiment running eight line surveys was conducted to collect USBL positioning data. The numerical results for the sea trial data demonstrated that the proposed algorithm could robustly and effectively estimate the alignment errors. Comparisons of the experimental result with the analytical prediction of roll misalignment estimation in Part I is drawn, showing good agreement. The experimental results also show that an inappropriate estimation of roll alignment error will significantly degrade the quality of estimations of heading and pitch alignment errors.

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Evaluation of Ship Performance Using Operation Records

10.5957/pss-2018-07 ◽

2018 ◽

Author(s):

Kenichi Fukuda ◽

Yoshihisa Okada ◽

Akinori Okazaki ◽

Hiroyuki Adachi ◽

Yuichiro Hisamuara ◽

...

Keyword(s):

Big Data ◽

Fuel Oil ◽

Time Dependent ◽

Oil Consumption ◽

Sea Trial ◽

Before And After ◽

Report Data ◽

Unique Approach ◽

Performance Conditions ◽

Ship Performance

Recently, the big data can be employed as the economical ship operating or evaluation of ship performance conditions. However, such data cannot be easily obtained and analyzed for every ship. In this case, for example, an evaluation of ship performance during operation is usually dependent on ship owner’s experience. The time-dependent ship performance is an essential topic for ship owners because if they realize their current ship performance, they can implement something such as hull or propeller cleaning for their economical operation. This study is focused on the usage of noon report data rather than the big data due to their obtainability. Usually, such data are considered as references because different ship operational condition and environmental condition obscure current ship performance. However, our unique approach, which is used integrally the noon report data such as BHP, propeller revolution and fuel oil consumption, ship sea trial data and propeller performance, can be evaluated ship performance during ship in service. The analyzed output data can be produced as increasing of ship resistance (delta Rw) versus ship performance efficiency, fuel oil consumption (ton per day) or sea margin. Under this output conditions, it can be comparable at same conditions even though the conditions of operations are different. Therefore, this analyzed data has a potential ability to have a look at ship performance conditions during ship in service. The purpose of this paper is to introduce our unique approach using noon data for time-dependent ship performance and then discuss the verification of this approach. As the case study, the noon report data for Japanese domestic bulker was chosen and the ship performance was evaluated in terms of different points of views. It was done comparing the conditions of before and after dry dock to evaluate our approach. In addition, the potential application of this approach will be discussed in this paper.

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