Dynamic Interaction Analysis of a 2D Propulsion Shaft-Ship Hull System Subjected by Sea Wave

Volume 4A: Structures, Safety and Reliability ◽

10.1115/omae2014-23795 ◽

2014 ◽

Cited By ~ 1

Author(s):

Zhe Tian ◽

Xinping Yan ◽

Zhixiong Li ◽

Cong Zhang

Keyword(s):

Large Scale ◽

Interaction Analysis ◽

Coupled System ◽

Ship Hull ◽

Propulsion System ◽

Coupling Mechanism ◽

Sea Waves ◽

Ship Propulsion ◽

Large Ship ◽

Sea Wave

Since there is an evident tendency of development of large scale ships, the interaction between the propulsion shaft and ship hull becomes severe due to the tremendously increased ship size. As a result the reliability of the vessels has been put in an important position by the companies and the governments all over the world. The excited forces caused by severe sea waves have considerable effects on the hull deformation which could have further impact on the shaft propulsion system. This paper aims to investigate the coupling dynamics between the large ship propulsion system and hull subjected by sea wave in 2-dimensional circumstance. To look into the coupling mechanism between the ship propulsion shaft, hull and sea waves, a 2-dimensional novel model of large ship propulsion-hull coupling system is presented in this work to analyze the dynamic interactions of the ship propulsion system and hull. According to the dynamic equations of the coupling model, the dynamical responses of the ship shaft and hull are obtained under different stiffness of the support bearings. The analysis indicates that choosing the suitable stiffness of bearings have an important effect on the coupled system.

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Simulation on the Dynamic Behavior of the Propulsion System Subjected by Hull Deformation for Large Vessels

Volume 3: Structures, Safety and Reliability ◽

10.1115/omae2015-42391 ◽

2015 ◽

Author(s):

Zhe Tian ◽

Xinping Yan ◽

Cong Zhang ◽

Weizhong Tan

Keyword(s):

Dynamic Behavior ◽

Large Scale ◽

Propulsion System ◽

Normal Operation ◽

Sea Waves ◽

Ship Propulsion ◽

Coupling System ◽

Large Ship ◽

Important Position ◽

Large Vessels

This paper aims to investigate the dynamic behavior of the large ship propulsion system subjected by hull deformation. Evident tendency of development of large scale ships was shown that the interaction between the propulsion shaft and ship hull becomes much severer than before. The excited forces caused by severe sea waves have considerable effects on the hull deformation which could have further impact on the shaft propulsion system. On the contrary, the operation quality of ships and the durability of machines are threatened by the malfunctions of shaft propulsion system. As a result the reliability of the vessels has been put in an important position by the companies and the governments all over the world. For scientists, investigating the dynamic behavior of the propulsion system subjected by the hull deformation is a meaningful research to avoid malfunction of machine in navigation. Numerical analysis is now an effective method to analyze some key components on large vessels. Taking the 8530TEU container as an example, a numerical model of the large ship propulsion-hull coupling system is presented in this paper to analyze the dynamic behavior of the ship propulsion system subjected by hull deformation. The hull deformations are obtained under different sea conditions as the exciting forces which are used on the coupling system. Then the dynamical responds of the ship shaft are obtained. Based on the results, suggestions are proposed to ensure the normal operation of the propulsion system in different sea conditions.

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The Track and Accompanying Sea Wave Forecasts of the Supertyphoon Mangkhut (2018) by a Real-Time Regional Forecast System

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-19-0196.1 ◽

2020 ◽

Vol 37 (11) ◽

pp. 2075-2084

Author(s):

Yuhang Zhu ◽

Yineng Li ◽

Shiqiu Peng

Keyword(s):

Real Time ◽

Large Scale ◽

Negative Impact ◽

Wave Model ◽

Forecast Skill ◽

Track Forecast ◽

Sea Waves ◽

Mean Error ◽

Forecasting System ◽

Sea Wave

AbstractThe track and accompanying sea wave forecasts of Typhoon Mangkhut (2018) by a real-time regional forecasting system are assessed in this study. The real-time regional forecasting system shows a good track forecast skill with a mean error of 69.9 km for the forecast period of 1–72 h. In particular, it predicted well the landfall location on the coastal island of South China with distance (time) biases of 76.89 km (3 h) averaging over all forecasting made during 1–72 h and only 3.55 km (1 h) for the forecasting initialized 27 h ahead of the landfall. The sea waves induced by Mangkhut (2018) were also predicted well by the wave model of the forecasting system with a mean error of 0.54 m and a mean correlation coefficient up to 0.94 for significant wave height. Results from sensitivity experiments show that the improvement of track forecasting skill for Mangkhut (2018) are mainly attributed to application of a scale-selective data assimilation scheme in the atmosphere model that helps to maintain a more realistic large-scale flow obtained from the GFS forecasts, whereas the air–sea coupling has slightly negative impact on the track forecast skill.

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Ship-Borne Transfer Alignment under Low Maneuver

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.152-154.1155 ◽

2012 ◽

Vol 152-154 ◽

pp. 1155-1158 ◽

Cited By ~ 2

Author(s):

Xin Liu ◽

Bo Wang ◽

Zhi Hong Deng ◽

Shun Ting Wang

Keyword(s):

Dynamic Deformation ◽

Angular Rate ◽

Estimation Accuracy ◽

Sea Waves ◽

Transfer Alignment ◽

Large Ship ◽

Matching Filter ◽

Simulation Results ◽

Sea Wave

The transfer alignment processes of the ship-borne weapon and the shipboard aircraft are limited by ship0s maneuver, for large ship, it is hope that the transfer alignment can be executed just under the circumstances of sea wave without any intentional ship0s maneuver. Attitude plus angular rate matching and velocity plus attitude matching as the two possible methods which can give accurate estimations of misalignments between MINS and SINS just under swaying maneuver are studied in this paper. Simulation results show that under the circumstance of sea waves and parameters of ships dynamic deformation, attitude plus angular rate matching filter can give better estimations of misalignment angles than velocity plus attitude matching filter. In addition, the estimation accuracy of attitude plus angular rate matching filter is barely affected by sea condition.

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Dynamic Stability Research On the DCT Marine Propulsion System with Unsymmetrical Load

Journal of Computational and Nonlinear Dynamics ◽

10.1115/1.4051995 ◽

2021 ◽

Author(s):

Jianghai Xu ◽

Chunxiao Jiao ◽

Donglin Zou ◽

na ta ◽

Zhushi Rao

Keyword(s):

Large Scale ◽

Excitation Frequency ◽

Load Ratio ◽

Coupled System ◽

Propulsion System ◽

System Stability ◽

Unstable State ◽

Finite Width ◽

Gear Pair ◽

The Stability

Abstract The DCT (double-cylinder turbines) propulsion system is widely applied to large-scale ships, while the instability mechanism of the system lacks theoretical and scientific research. Based on gear transmission principle and finite width journal bearings theory, the lateral-torsional-axial model of the system considering multiple nonlinear and time-varying factors is established. The effects of the unsymmetrical load parameters on the stability of the coupled system have been explored and quantified. Results indicate that the phenomenon of instability gradually occurs with the increase of excitation frequency, the decrease of load ratio between the two inputs or the decrease of input load value, and the vibration of the gear pair on the low load side is more severe. Furthermore, the vibration amplitude is not only related to the load parameters but also the distance between the gear pair and the load input disc. Finally, the influence of the oil whip on the system stability is crucial, especially when the system is in an unstable state. This study provides a theoretical reference for the optimization and adjustment of such propulsion system.

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Analysis of Torsional Vibration of Large-Scale Ship Propulsion Shafting

Volume 3: Structures, Safety and Reliability ◽

10.1115/omae2015-42392 ◽

2015 ◽

Author(s):

Weizhong Tan ◽

Cong Zhang ◽

Zhe Tian ◽

Xinping Yan

Keyword(s):

Torsional Vibration ◽

Large Scale ◽

Ship Hull ◽

Dynamic Coupling ◽

The Real ◽

Ship Propulsion ◽

Torsion Vibration ◽

Simulation Results ◽

Multi Body ◽

Body Dynamic

This paper is based on the multi-body dynamic coupling theory and finite element theory. A multi-body dynamic coupling model of the large-scale vessel is built and the torsion vibration characteristics of slow-speed ship propulsion shafting are analyzed. The measurements of shafting torsional vibration in the real ship are compared with the results from the simulation model. Then, the differences between measurements and simulation results are analyzed in multi-orders. The analysis result indicates that the simulation results are almost the same with measurements obtained from the real ship, which verify the correctness and feasibility of the model. At the same time, the influence of ship hull deformation on the torsion vibration of ship propulsion shafting is discussed by Adams/Vibration. The analysis shows that the ship hull deformation could cause the significant increase of torsional vibration of ship propulsion shafting.

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Soil/Tire Interaction Analysis Using FEM and FVM

Tire Science and Technology ◽

10.2346/1.2186786 ◽

2005 ◽

Vol 33 (1) ◽

pp. 38-62 ◽

Cited By ~ 17

Author(s):

S. Oida ◽

E. Seta ◽

H. Heguri ◽

K. Kato

Keyword(s):

Large Scale ◽

Interaction Analysis ◽

Yield Criterion ◽

Surrounding Medium ◽

Flow Analysis ◽

Measurement Data ◽

Traction Force ◽

Elastoplastic Material ◽

The Road ◽

Soil Flow

Abstract Vehicles, such as an agricultural tractor, construction vehicle, mobile machinery, and 4-wheel drive vehicle, are often operated on unpaved ground. In many cases, the ground is deformable; therefore, the deformation should be taken into consideration in order to assess the off-the-road performance of a tire. Recent progress in computational mechanics enabled us to simulate the large scale coupling problem, in which the deformation of tire structure and of surrounding medium can be interactively considered. Using this technology, hydroplaning phenomena and tire traction on snow have been predicted. In this paper, the simulation methodology of tire/soil coupling problems is developed for pneumatic tires of arbitrary tread patterns. The Finite Element Method (FEM) and the Finite Volume Method (FVM) are used for structural and for soil-flow analysis, respectively. The soil is modeled as an elastoplastic material with a specified yield criterion and a nonlinear elasticity. The material constants are referred to measurement data, so that the cone penetration resistance and the shear resistance are represented. Finally, the traction force of the tire in a cultivated field is predicted, and a good correlation with experiments is obtained.

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