Journal articles on the topic 'Shafting'
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1
Wang, Wuchang, Yizi Shang, and Zhifeng Yao. "A Predictive Analysis Method of Shafting Vibration for the Hydraulic-Turbine Generator Unit." Water 14, no. 17 (August 31, 2022): 2714. http://dx.doi.org/10.3390/w14172714.
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The shafting vibration for the Hydraulic-Turbine Generator Unit (HGU) inevitably affects the safe and stable operation of the Units. Excessive shafting vibration could cause fatigue damage of materials, which eventually leads to malfunction of HGU and even results in damage accidents in serious cases. Generally speaking, the vibration is mainly generated from the high-speed rotation of the shafting, and mechanical, hydraulic, and electrical factors as the vibration exciting sources may be coupled all to cause a vibration of the HGU, so it is necessary to take the whole shafting as a specific object of study. In recent years, many scholars have conducted much research on them and their results are focused more on how to control the influence of external excitation sources of vibration, but still lack consideration of the shafting’s internal mechanism of vibration. In this paper, a predictive analysis method is proposed to reveal the internal mechanism of vibration. Starting from the analysis of natural vibration characteristics of the shafting, this study establishes the finite element calculation model of the shafting of the HGU based on the finite element analysis method. By selecting appropriate research methods and calculation procedures, the modal analysis of the dynamic characteristics of the shafting structure is carried out. Finally, the first ten-order natural vibration characteristics and critical rotational speed of the shafting structure are successfully calculated, and the results conform to the basic laws of shafting vibration. In addition, by comparing the relationship between rotational frequency such as the rated speed, runaway speed, and critical speed of the shafting, the possibility of resonance of the HGU is analyzed and predicted, and then some suggestions for optimization design such as increasing the shafting’s stiffness and balancing its mass distribution are proposed. Therefore, this study provides a basis for guiding the structural design and optimization of the shaft system in engineering, and avoids the resonance caused by the excitation source such as rotational frequency, thereby ensuring the safe and stable operation of the HGU.
2
Changyou, Huang, and Hu Jianzhong. "Theoretical Study on the Nonlinear Dynamic Response of Propulsion Shafting under Time-Varying Hull Motion." Journal of Physics: Conference Series 2542, no. 1 (July 1, 2023): 012021. http://dx.doi.org/10.1088/1742-6596/2542/1/012021.
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Abstract Due to the effect of external elements such sea waves and sea wind, the ship will unavoidably produce 6 degrees of freedom of movement, with roll motion being the most likely to occur and having the greatest impact. This paper establishes a general dynamic model of the propulsion shafting based on Timoshenko beam theory, the concentrated mass method, and Lagrange’s equation under roll motion and translation motion to study the dynamic behaviour of the propulsion shafting under roll motion and translation motion. FFT, axis trajectory, Poincaré map, and 3D spectrogram were utilized to examine the impact of motion amplitude, frequency, and rotation speed on the propulsion shafting’s dynamic response. The results demonstrated that base motion significantly affects the dynamics of the propulsion shafting, resulting in many components appearing in the system’s response spectrum, and the system changes from quasi-periodic to chaotic motion when base motion amplitude or frequency rises.
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Liu, Shi, Cong Wang, Bing Li, Chang Chen, and Dan Mei Xie. "Sensitivity Analysis of 1000MW USC Units Shafting Torsional Vibration Based on ANSYS." Applied Mechanics and Materials 226-228 (November 2012): 162–65. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.162.
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To calculate a shaftings natural frequency of torsional vibration is one of the most important tasks in turbo-generators design, manufacture and frequency adjusting process. The sensitivity analysis of shafting structural parameters impact on the torsional vibration characteristics has important significance in reducing the amplitude of torsional vibration and ensuring the turbo-generators safe operation. In this paper, a 1000MW USC unit was taken as a research object to analyze the shaftings sensitivity to moment of inertia.
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Wen, Xiaofei, Wenjie Meng, Xiaoxiao Sun, and Ruiping Zhou. "A Composite Method of Marine Shafting’s Fault Diagnosis by Ship Hull Vibrations Based on EEMD." Shock and Vibration 2022 (March 30, 2022): 1–11. http://dx.doi.org/10.1155/2022/1236971.
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The fault diagnosis is always a key issue in the security field of marine propulsion system. There are obvious problems like the unsteady working of sensors, distortion of original data, and ambivalent feature information from marine shafting’s vibration or motion. It is therefore critical to develop a more effective method to identify the fault information so that the safety of marine propulsion system can be pre-estimated. Hence, a composite method which is based on the ensemble empirical mode decomposition (EEMD) and coupled with the autocorrelation method (AM), the fast Fourier transform (FFT), is mixed and applied to identify the fault information of marine shafting during its operating by hull vibration. The contrastive analysis of the three methods and fault feature study are then conducted to assess the effectiveness of the proposed method thoroughly and validated by the author previously. The research indicates that the composite method is available to fault diagnosis of marine shafting by hull vibration which coupled the shafting vibration with fault feature.
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Deng, Yibin, Yuefan Li, Hanhua Zhu, and Shidong Fan. "Displacement Values Calculation Method for Ship Multi-Support Shafting Based on Transfer Learning." Journal of Marine Science and Engineering 12, no. 1 (December 22, 2023): 36. http://dx.doi.org/10.3390/jmse12010036.
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Deviations between the design and actual shafting occur due to limitations in ship construction accuracy. Consequently, accurately obtaining the relationship between the actual shafting load and displacement relationship based on the design shafting becomes challenging, leading to inaccurate solutions for bearing displacement values and low alignment efficiency. In this research article, to address the issue of incomplete actual shafting data, a transfer learning-based method is proposed for accurate calculation of bearing displacement values. By combining simulated data from the design shafting with measured data generated during the adjustment process of the actual shafting, higher accuracy can be achieved in calculating bearing displacement values. This research utilizes a certain shafting as an example to carry out the application of the bearing displacement value calculation method. The results show that even under the action of shafting deviation, the actual shafting load and displacement relationship model can become more and more accurate with the shafting adjustment process, and the accuracy of bearing displacement values calculation becomes higher and higher. This method contributes to obtaining precise shafting adjustment schemes, thereby enhancing alignment quality and efficiency of ship shafting.
6
Liang, Xing Xin, Zheng Lin Liu, and Jiao Liu. "Study of Frequency Converter Motor Selection Method of Shafting Test Bed." Advanced Materials Research 912-914 (April 2014): 922–26. http://dx.doi.org/10.4028/www.scientific.net/amr.912-914.922.
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The rotary inertia, speed, acceleration of shafting and the friction coefficient of rubber bearings have an important influence on the calculation of shafting resistance moment, related to the selection rationality of driving motor. In order to guarantee load startup and normal operation of the shafting, by analysing shafting rotary inertia, bearing support force and friction coefficient, calculated resistance moment of the shafting, established the mathematical model of shafting equivalent resistance moment and motor rotational speed, compared the output moment of motor with shafting equivalent resistance moment, so that determined the correct motor model.
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Lei, Junsong, Ruiping Zhou, Hao Chen, Guobing Huang, Yakun Gao, and Qingcao Yang. "Effects of Ship Propulsion Shafting Alignment on Whirling Vibration and Bearing Temperature Response." Mathematical Problems in Engineering 2021 (September 27, 2021): 1–10. http://dx.doi.org/10.1155/2021/8353844.
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Ship’s propulsion shafting is one of the main sources of ship vibration and noise. The shafting, whirling vibrations, and alignment are important factors that affect the comfort, stability, and reliability during a ship’s navigation. However, the mechanism of the interacting of the both factors is not fully revealed. In this paper, the effect of shafting alignment on whirling vibration and the bearing temperature response is studied by experiment. The test scheme is designed reasonably according to the theoretical analysis. The results show that the horizontal component of the shafting whirling vibration can be effectively reduced by adjusting the shafting alignment state while the vertical component is not. The shafting axis balancing position (SABP) slightly moves upward in high speed, which should be considered in the dynamic alignment design of the shafting, especially for the high-speed shafting. Little ABSB (the angle between the shafting centre line and the No. 1 bearing centre line) is beneficial to the stable operation of shafting, while appropriately increasing the ABSB and bearing load is beneficial to reducing the shafting whirling vibration. By balancing the relationship between bearing load and ABSB, the performance of whirling vibration and bearing temperature response can be optimized.
8
Liu, Jinlin, Zheng Gu, and Shuyong Liu. "Research on MDO of Ship Propulsion Shafting Dynamics Considering the Coupling Effect of a Propeller-Shafting-Hull System." Polish Maritime Research 30, no. 1 (March 1, 2023): 86–97. http://dx.doi.org/10.2478/pomr-2023-0009.
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Abstract Dynamic designs for ship propulsion shafting can be categorised as complex multi-disciplinary coupling systems. The traditional single disciplinary optimisation design method has become a bottleneck, restricting the further improvement of shafting design. In this paper, taking a complex propulsion shafting as the object, a dynamic analysis model of the propeller-shafting-hull system was established. In order to analyse the coupling effect of propeller hydrodynamics on shafting dynamics, the propeller’s hydrodynamic force in the wake flow field was calculated as the input for shafting alignment and vibration analysis. On this basis, the discipline decomposition and analysis of the subdisciplines in design of shafting dynamics were carried out. The coupling relationships between design variables in the subdisciplines were studied and the Multi-disciplinary Design Optimisation (MDO) framework of shafting dynamics was established. Finally, taking the hollowness of the shaft segments and the vertical displacement of bearings as design variables, combined with the optimal algorithm, the MDO of shafting dynamics, considering the coupling effect of the propeller-shafting-hull system, was realised. The results presented in this paper can provide a beneficial reference for improving the design quality of ship shafting.
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Xiao, Nengqi, Ruiping Zhou, Xiang Xu, and Xichen Lin. "Study on Vibration of Marine Diesel-Electric Hybrid Propulsion System." Mathematical Problems in Engineering 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/8130246.
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This study analyzes the characteristics of hybrid propulsion shafting and builds mathematical models and vibration equations of shafting using the lumped parameter method. Main focus is on the asymmetric double diesel propulsion shafting operation process and the impact of the phase angle and motor excitation on torsional vibration of shafting. Model result is validated by testing results conducted on double diesel propulsion shafting bench. Mathematical model and model-building methods of shafting are correct.
10
Shuo, Chen, and Zhang Heng. "Vibration analysis of ship propulsion shafting bearings." E3S Web of Conferences 233 (2021): 01007. http://dx.doi.org/10.1051/e3sconf/202123301007.
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The ship power propulsion system is the "heart" of the ship, and the ship propulsion shafting is the core unit of the ship power propulsion system, and it is an indispensable part of the ship's propulsion torque and thrust transmission. The operating status of the propulsion shafting directly affects the operating conditions of the ship, and even the life of the ship. Bearing load is one of the most important manifestations of the operating state of the propulsion shafting. Focusing on changes in the bearing load can better study the operating state of the propulsion shafting. The research on the steady-state load of ship propulsion shafting meets the needs of ship development and has great value for practical engineering applications. This paper takes the ship propulsion shafting-oil film-bearing structure system as the research object. Through the steady-state load mathematical model of ship propulsion shafting bearings, it reveals the coupling relationship among ship propulsion shafting bearing load, oil film force, and journal position, and establishes the ship The steady-state load calculation method of the propulsion shafting bearings solves the basic theoretical problems of modeling and analysis of the steady-state operating state of the ship's propulsion shafting, and provides theoretical support for the safety prediction, management and evaluation of the ship's propulsion shafting operation.
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Tian, Yaqi, Cong Zhang, Lei Yang, Wu Ouyang, and Xincong Zhou. "Analysis of Vibration Characteristics of Podded Propulsor Shafting Based on Analytical Method." Journal of Marine Science and Engineering 10, no. 2 (January 27, 2022): 169. http://dx.doi.org/10.3390/jmse10020169.
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Podded propulsors are widely used in warships and cruise ships, which have a higher requirement of vibrational and acoustic design. Therefore, studying vibration characteristics and the transmission mechanism of podded propulsor shafting is significant for reducing vibration and ensuring the safe operation of ships. This paper establishes a model of podded propulsor shafting by analytical method. The shafting is simplified to a heterogeneous variable cross-section beam, while bearings are seen as springs. The podded propulsor shafting has one radial-thrust hybrid bearing and one radial bearing. The excitations from the propeller and cabin are considered. The influences of bearing stiffness, bearing location, and excitation on vibration characteristics of shafting are analyzed. The main conclusions are as follows: Based on the analysis of the area that resonance frequency is sensitive to the change of bearing stiffness, the resonance frequencies of the shafting can be adjusted to the proper range. The large span between hybrid bearing and radial bearing leads to low stiffness of shafting and low resonances frequencies. Under radial excitations, the low vibration always occurs at the hybrid bearing, motor shafting, or propeller end of shafting. This research provides theoretical support for the design and optimization of vibration reduction of podded propulsor shafting.
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Xing, Pengfei, Lixun Lu, Guobin Li, Xin Wang, Honglin Gao, Yuchao Song, and Hongpeng Zhang. "A Multi-Method Approach to Identify the Natural Frequency of Ship Propulsion Shafting under the Running Condition." Journal of Marine Science and Engineering 10, no. 10 (October 4, 2022): 1432. http://dx.doi.org/10.3390/jmse10101432.
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In order to identify the natural frequency of ship propulsion shafting under the running condition, a multi-method approach that combines Duffing Oscillator, harmonic wavelet packet transform, and probability density function is proposed. An experimental investigation on the natural frequency of running propulsion shafting is conducted on the ship propulsion shafting test bench, and the natural frequency response of running propulsion shafting under different alignment states is obtained from the measured bearing vibration signal. The results show that the natural frequency of propulsion shafting can be excited under the running condition, but its response is feeble. When the alignment state of the propulsion shafting gradually changes with the elevation of the front stern bearing, the identified natural frequency of the propulsion shafting shows an upward trend. In contrast, its amplitude shows a downward trend. Therefore, the proposed approach can identify the natural frequency of the ship propulsion shafting from the measured bearing vibration signal under the running condition.
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Zeng, Yun, Li Xiang Zhang, Jing Qian, and Cheng Li Zhang. "Shafting Vibration Simulation for Hydro Turbine Generating Sets." Applied Mechanics and Materials 444-445 (October 2013): 1171–76. http://dx.doi.org/10.4028/www.scientific.net/amm.444-445.1171.
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Based on the transient model of hydro turbine generating sets (HTGS), the integrated simulation system of HGTS is built to study shafting stability. Given different bearing stiffness, equivalent damping coefficient and mass eccentricity, the change characteristics of shafting vibration at rated angular speed in steady and maximum angular speed in transient are simulated, and which are applied to study inferences shafting parameters and angular speed on shafting vibration. Simulation results show that the relationship between shafting vibration amplitude and angular speed is linear. however, the vibration amplitude increment produced by angular speed error will be amplified while the shafting stiffness is weaker, mass eccentricity of the runner and rotor is larger.
14
Huang, Zhong Hua, Ya Xie, and Yi Deng. "Hybrid Excavator Shafting Torsional Vibration Analysis." Applied Mechanics and Materials 268-270 (December 2012): 1262–65. http://dx.doi.org/10.4028/www.scientific.net/amm.268-270.1262.
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Hybrid excavator shafting finite element analysis model was established. Modal calculation results show that compared with traditional excavator, hybrid excavator shafting first modal frequency is decreased significantly. First modal shape and second modal shape are torsional vibration. Hybrid excavator shafting torsional vibration dynamic analysis model was established, dynamic calculation results show that cylinder pressure change is main reason of shafting torsional vibration. Maximum torsional angle is occurred at 2f0. Hybrid excavator shafting torsional vibration experimental table was established and maximum torsional angel experiments under different throttle angle were carried out. Experimental results show that maximum torsional angle is occurred at 2f0 under different rotate speed. Incentive frequency of shafting torsional vibration under different rotate speed is mainly concentrated in 0.5f0~2f0. Main drive source of hybrid power system shafting torsional vibration is diesel engine, not motor.
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Huang, Bing Yang, Gang Liu, and Zhi Gang Hua. "Research on Influence of CPP Oil Tubes Disposition on Shafting Vibration." Advanced Materials Research 317-319 (August 2011): 446–50. http://dx.doi.org/10.4028/www.scientific.net/amr.317-319.446.
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This paper presents a thorough study of a certain CPP shafting and analyzes the shafting natural vibration characteristic using FEM. Simulate the influences of CPP oil tubes on shafting natural frequency and compare it to hollow shaft natural frequency, then acquire the influencing law of CPP oil tubes disposition on the shafting vibration characteristic.
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Chen, Qian, Qi Yuan, Ming Lei, and Mengyao Wang. "Shafting Alignment Computing Method of New Multibearing Rotor System under Specific Installation Requirement." Mathematical Problems in Engineering 2016 (2016): 1–12. http://dx.doi.org/10.1155/2016/1647575.
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The shafting of large steam turbine generator set is composed of several rotors which are connected by couplings. The computing method of shafting with different structure under specific installation requirement is studied in this paper. Based on three-moment equation, shafting alignment mathematical model is established. The computing method of bearing elevations and loads under corresponding installation requirements, where bending moment of each coupling is zero and there exist preset sag and gap in some couplings, is proposed, respectively. Bearing elevations and loads of shafting with different structure under specific installation requirement are calculated; calculation results are compared with installation data measured on site which verifies the validity and accuracy of the proposed shafting alignment computing method. The above work provides a reliable approach to analyze shafting alignment and could guide installation on site.
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Li, Rui, Ji Wang, Ziqi Chen, Feixiang Wang, and Yujun Liu. "Study on the Methods of Measurement, Optimization and Forecast of Propulsion Shaft Bearing Load of Ships." Journal of Marine Science and Engineering 11, no. 7 (June 29, 2023): 1324. http://dx.doi.org/10.3390/jmse11071324.
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The qualit12y of shafting alignment is related to the reliability and safety of a ship’s operation, and bearing displacement adjustment (BDA) plays a key role in shafting alignment. To solve the problems encountered in ship shafting alignment in the actual construction, this study focused on the investigation of the shafting load measurement system based on the strain gauge method (SGM), used the optimization method based on quadratic programming (QP) to calculate the BDA and adopted algorithms based on the bearing load influence coefficients (BICs) to forecast the load after the adjustment. The experimental work, as well as the measurement, calculation and analysis of several real ships, indicated that the measurement, optimization and forecasting methods of the bearing load of the propulsion shafting of large ships in this study would be significant for guiding the actual construction work of ship shafting alignment.
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Ning, Xin, Songlin Zheng, and Wenlong Xie. "Design principle of active load spectrum for shafting components in wheel hub reducer of electric vehicle." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 10 (October 3, 2018): 2546–58. http://dx.doi.org/10.1177/0954407018800569.
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Design principle of active load spectrum is proposed for the lightweight design of shafting components. The characteristics of fatigue and the strengthening effect of low-amplitude load are conducted according to the material properties of the shafting components. The stress–life curve and three-dimensional surface of low-amplitude strengthening load are established for the life calculation of shafting components. Fast calculation method of working stress for variable size of shafting components is obtained considering the road cycle in Shanghai, the load spectrum is extrapolated, the torque working condition which is equivalent to load spectrum of 3000 km is achieved, and the fatigue damage and strengthening proportion of working stress spectrum of shafting components are adjusted, finally the minimum size of shafting components is designed to meet the requirement of service life. The design principle of active load spectrum can provide a new idea for the lightweight design of automotive components.
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Liu, Gang, Bing Yang Huang, and Zhi Gang Hua. "Research on Whirling Vibration of CPP Propulsion Shafting." Advanced Materials Research 308-310 (August 2011): 2537–42. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.2537.
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The parameters influencing the whirling vibration characteristic is more for the CPP (Controllable-Pitch Propeller) propulsion shafting, comparing to the traditional shafting. Verified by a ship’s CPP propulsion shafting, the method of transfer matrices is used for analyzing whirling vibration, by building a hybrid model fosr lumped parameter elements and distributed parameter elements. Then the parameters influencing the whirling vibration characteristic are analyzed, which could provide evidence for the analysis on the whirling vibration for the CPP propulsion shafting.
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An, Feng Bao, Ping Yang, Xin Ping Yan, and Ming Li. "Influence Analysis of Hull Deformation on Dynamic Behavior of Propulsion Shafting." Advanced Materials Research 904 (March 2014): 432–36. http://dx.doi.org/10.4028/www.scientific.net/amr.904.432.
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The aim of this paper is to study the influence of hull deformation on dynamic behavior of ship propulsion shafting. Taking an 8530TEU container ship as an objective and using the finite element method, a global ship structure model is built up to evaluate the hull deformations under typical loading cases. Then the hull bottom-propulsion shafting integrated model is adopted to analyze the effect of hull deformation on shafting natural frequency under dry and wet mode. The results show that the natural frequencies of the shafting will increase due to the effect of hull deformation. Consequently, it is necessary to consider the effect of ship deformation when dealing with the dynamic behavior of ship propulsion shafting.
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Magazinovic, Gojko. "Regression-Based Assessment of Shafting Torsional Vibration Key Responses." Marine Technology and SNAME News 47, no. 01 (January 1, 2010): 65–73. http://dx.doi.org/10.5957/mtsn.2010.47.1.65.
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A novel procedure for the assessment of propulsion shafting torsional vibration key responses is proposed in this paper. The procedure is based on the response surface methodology applied to a set of system responses compiled over a selected design space. Design space of 1250 design points comprising the shafting stiffness, propeller, turning wheel, and tuning wheel mass moments of inertia coordinates has been employed to build the first torsional natural frequency, crankshaft peak vibration torque, and shafting peak vibration torque quadratic polynomial approximations. Statistical evaluation performed on a full test set of 2500 design points showed that the mean relative errors of 0.14% for natural frequency, 2.93% for crankshaft peak vibration torque, and 0.41% for shafting peak vibration torque were achieved. Good agreement between the assessed and actual torsional responses stresses the importance and utility of the proposed metamodels for the propulsion shafting preliminary design purposes. An example application based on the 114,000 dwt tanker propulsion shafting is also provided.
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Qin, Hui, Hongbo Zheng, Wenyuan Qin, and Zhiyi Zhang. "Lateral vibration control of a shafting-hull coupled system with electromagnetic bearings." Journal of Low Frequency Noise, Vibration and Active Control 38, no. 1 (November 18, 2018): 154–67. http://dx.doi.org/10.1177/1461348418811516.
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In order to suppress lateral vibration transmission and reduce acoustic radiation of a shafting-hull coupled system, a new approach using electromagnetic bearings in the shafting system is proposed. The dynamic characteristics of the electromagnetic bearings, especially the equivalent stiffness and damping as well as the applicable scope of linearization of the electromagnetic bearings, are analysed at first. With the equivalent parameters, a dynamic model of the shafting-hull coupled system is established subsequently by using the frequency response synthesis method to derive frequency response functions associated with the lateral vibrations. Finally, the influence of the control parameters of the electromagnetic bearings on vibration transmission in the shafting-hull system is studied. Analysis results indicate that lateral vibration responses are suppressed significantly when electromagnetic bearings are introduced into the shafting-hull system, and as a result, sound radiation of the system is reduced, which demonstrates that the proposed approach is effective in controlling vibration transmission in the shafting system.
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Wen, Xiao Fei, Qiang Yuan, Jin Shu Lu, and Zhen Dong Cui. "Analysis of Propulsion Shafting Torsional Vibration of Vessels with Double Engines and Double Propellers." Advanced Materials Research 479-481 (February 2012): 1310–13. http://dx.doi.org/10.4028/www.scientific.net/amr.479-481.1310.
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The powerful propulsion system of vessels with double engines and double propellers is commonly used for harbor utility crafts, offshore platform supply vessels and etc.. Their shafting torsional vibration evaluation methods differ from those of one-engine vessels, so it is necessary to use appropriate methods to get scientific evaluation results of the two kinds of shafting. For vessels with double engines and double propellers, the shafting torsional vibration is calculated theoretically by specialized calculation software; a practical scheme is designed and put into use to the real ship testing. The torsional vibration test data of four sets of propulsion shafting of two ships were collected and analyzed. The preliminary results drawn from the analysis can provide references for ship shafting torsional vibration test and analysis.
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Shi, Yousong, Jianzhong Zhou, Jie Huang, Yanhe Xu, and Baonan Liu. "A Vibration Fault Identification Framework for Shafting Systems of Hydropower Units: Nonlinear Modeling, Signal Processing, and Holographic Identification." Sensors 22, no. 11 (June 3, 2022): 4266. http://dx.doi.org/10.3390/s22114266.
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The shafting systems of hydropower units work as the core component for the conversion of water energy to electric energy and have been running for a long time in the hostile hydraulic–mechanical–electrical-coupled environment—their vibration faults are frequent. How to quickly and accurately identify vibration faults to improve the reliability of the unit is a key issue. This study proposes a novel shafting vibration fault identification framework, which is divided into three coordinated stages: nonlinear modeling, signal denoising, and holographic identification. A nonlinear dynamical model of bending–torsion coupling vibration induced by multiple excitation vibration sources of the shafting system is established in the first stage. The multi-stage signal denoising method combines Savitzky–Golay (SG) smoothing filtering, singular value decomposition (SVD), and variational mode decomposition (VMD). SG-SVD-VMD is used for the guide bearing the vibration signals in the second stage. Further, the holospectrum theory is innovatively introduced to obtain the holospectra of the simulated and measured signals, and the shafting vibration faults of the real unit are identified by comparing the holospectrum of the measured signal with the simulated signal. These results show that the shafting nonlinear model can effectively reflect the vibration characteristics of the coupled vibration source and reveal the influence and fault characteristics of each external excitation on the shafting vibration. The shafting vibration faults of operating units can be identified by analyzing the holospectra of the shafting simulation signals and measuring the noise reduction signals. Thus, this framework can guide the safe and stable operation of hydropower units.
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Leontopoulos, Chris, Charalampos Mouzakis, and Michail Petrolekas. "Smart Bearing Sensor." Journal of Ship Production and Design 36, no. 01 (February 1, 2020): 67–77. http://dx.doi.org/10.5957/jspd.2020.36.1.67.
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The recent increase in vessel shaftline bearing incidents indicates that a static shaft alignment design may not be suitable for all operational shaftline loading conditions. Hull deflections caused by vessel loading or propeller loads initiated by interaction with the wakefield have become important considerations in modern vessel design. Jack-up tests, typically used as a bearing load verification method, can only be accomplished under static shaft conditions and cannot verify the shaft dynamic behavior under running operational conditions. A newly developed sensor using strain gauge technology measures the bearing load and the shaft misalignment angle through the bearing housing's deformation-induced strain. It effectively converts the bearing housing into a weighing machine by mapping the bearing housing strain onto the bearing load. Unlike jack-up tests, this method allows for the continuous measurement of the bearing load and misalignment angle under all shaftline operational conditions. It is envisaged that this technologically simple system will allow for the earliest possible diagnosis of shaft alignment-related problems, such as bearing unloading, bearing overloading, or excessive shaft-bearing misalignment. This provides a much earlier warning indicator when compared with the bearing temperature alarm. The subject technology has been tested on intermediate bearings and is considered for future application into stern tube bearings. 1. Introduction In post-IMO's (International Maritime Organization) Energy Efficiency Design Index vessel designs, the propulsion shafting arrangements become increasingly sensitive to shaft alignment with lower tolerances and margins, increasing the risk of stern tube bearing failures (Leontopoulos 2016a). This change is due to the wider use of more efficient, larger diameter propellers with increased cantilevered load on the shafting system and shorter shaftlines as a result of maximizing cargo space and minimizing engine room length. Widespread application of the single stern tube bearing design (an arrangement without a forward stern tube bearing) has also highlighted a decreased tolerance to eccentric propeller thrust and propeller forces in general. Reduced tolerance to shaft alignment sighting errors, bearing offset inaccuracies and other shaft installation errors, also affects the integrity of the shafting system and can result in complete bearing wiping with the consequence of vessel propulsion immobilization. This undesirable consequence has increased, particularly during the years 2013–2017.
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Feng, Wei Dong, Wen Xu, and Xian Hong Wang. "Error Analysis and Testing on Shafting Verticality for Horizontal Photoelectric Theodolite." Advanced Materials Research 791-793 (September 2013): 1002–5. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.1002.
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It is vitally important to improve effects of error compensation for horizontal photoelectric theodolite and reduce production costs by executing rational control of verticality error of shafting. This paper analyzes the mechanism how the verticality error of shafting influences measurement precision of photoelectric theodolite considering the architectural characteristics of the frame of horizontal theodolite. Matlab software has been used to simulate pointing accuracy. Verticality error of shafting of horizontal theodolite has been detected. Measured verticality error of shafting is 37 and detection error is 10. Results of analysis and detection to be applied for error compensation can improve pointing accuracy of the theodolite.
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Ding, Yu Feng, Lin Gan, Jun Bo Zhou, and Bu Yun Sheng. "Bearing-Rotor Coupled System Stability Optimization Design Based on Genetic Algorithm." Advanced Materials Research 199-200 (February 2011): 1130–33. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.1130.
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The structure parameter of sliding bearing has significant influence on entire shafting. The structural optimization of elliptical sliding bearing based on the genetic algorithm theory is studied in the paper. Shafting logarithmic decrement is taken as the objective function, the bearing width-diameter ratio, relative clearance and main design parameters such as ellipticity is taken as design variables. Mutual coupling effect between sliding bearing and rotor is considered in the optimization model. An elliptical sliding bearing of shafting has been optimized, and the solution result shows that the shafting stability has been increased, it indicates this method is feasible.
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Zeng, Yan Yan, Yun Zeng, Zhe Wu, and Shi Ge Yu. "Impact of the Unbalanced Magnetic Pull on the Shafting Vibration of Hydro Turbine Generating Sets." Applied Mechanics and Materials 644-650 (September 2014): 406–11. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.406.
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The unbalanced magnetic pull (UMP) of hydro turbine generating sets (HTGS) is one of the main reason induced vibration of the HTGS and the power plant. To study the effects of UMP on the shaft vibration characteristics of HTGS, this article constructs whole HTGS system which include hydraulic turbine and its hydraulic system, generator, transient model of the HTGS shafting, excitation and governing system, to simulate the actual operation of HTGS. The shafting vibration is simulated under different characteristics of UMP, simulation shows that the frequency resonance zone of the UMP has large influence on the shafting vibration. And then, the improved Prony algorithm is applied to extract the shafting oscillation characteristics of HTGS, and is effective. It provides a good method to research the effect of frequency and amplitude changes of UMP on the shafting vibration.
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TINGEY, RICHARD H. "BALANCING PROPULSION SHAFTING." Journal of the American Society for Naval Engineers 47, no. 1 (March 18, 2009): 14–24. http://dx.doi.org/10.1111/j.1559-3584.1935.tb04298.x.
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Komar, Ivan, Nenad Vulić, and Radovan Antonić. "Specifics of Shafting Alignmentfor Ships in Service." PROMET - Traffic&Transportation 21, no. 5 (March 2, 2012): 349–57. http://dx.doi.org/10.7307/ptt.v21i5.250.
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Modern ships are means of transport which, during their entire operational lifespan, need to convey cargo and/or passengers in a safe and reliable way, without jeopardising their safety, and with least possible adverse impacts on the marine environment. The ship’s safety and functionality directly depend on the reliability of her propulsion system, the shafting being the essential unit of the system. The functionality of the ship’s shafting considerably depends on its correct installation. Installation of the ship propulsion shafting is an integral part of the overall positioning (alignment) procedure. Shafting alignment is performed in several stages, starting with the shaft line design, and includes calculating the elastic line and bearing loads, installation of shafting parts onboard ship in compliance with the calculation results, and verifying the alignment results. Procedures are different for ships in service and newly built ships. This paper deals with specific features of the propulsion shafting alignment that is carried out while a ship in service is being converted for a general reason. Unlike a newly built ship, an existing ship imposes additional constraints that should be dealt with in the calculation stage of the process as well as during shafting installation and alignment verification. A calculation approach for ships in service is always different, having specific features from case to case, depending on what is changed and what remains unchanged during the conversion of the ship. The same goes for the implementation and verification of the achieved results. The purpose of this paper is to underline the difference, its contribution being in suggesting the procedure to be followed in case of conversion of an existing vessel. KEY WORDS: ship in service, shafting, alignment, GAP, SAG
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Ursolov, Aleksandr, Yuriy Batrak, and Wieslaw Tarelko. "Application of the Optimization Methods to the Search of Marine Propulsion Shafting Global Equilibrium in Running Condition." Polish Maritime Research 26, no. 3 (September 1, 2019): 172–80. http://dx.doi.org/10.2478/pomr-2019-0058.
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Abstract Full-film hydrodynamic lubrication of marine propulsion shafting journal bearings in running condition is discussed. Considerable computational difficulties in non-linear determining the quasi-static equilibrium of the shafting are highlighted. To overcome this problem the approach using two optimization methods (the particle swarm method and the interior point method) in combination with the specially developed relaxation technique is proposed. The developed algorithm allows to calculate marine propulsion shafting bending with taking into account lubrication in all journal bearings and exact form of journal inside bearings, compared to results of most of the publications which consider lubrication only in the aft most stern tube bearing and assume rest of bearings to be represented by points. The calculation results of typical shafting design with four bearings are provided. The significance of taking into account lubrication in all bearings is shown, specifically more exact values of bearings’ reactions, shafting deflections, minimum film thickness and maximum hydrodynamic pressure in the stern tube bearing in case of considering lubrication in all bearings.
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Xiao, Neng Qi, Ri Ping Zhou, and Xi Chen Lin. "Research on Marine Electric Propulsion Shafting under Electromechanical Coupling Condition." Applied Mechanics and Materials 607 (July 2014): 477–82. http://dx.doi.org/10.4028/www.scientific.net/amm.607.477.
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Through the establishment of motor electromechanical coupling vibration model, torsional vibration characteristics of motor is analyzed in starting process. With 1000T lubricating oil ship electric propulsion shafting as the object of study, the free vibration and the forced vibration characteristics are analyzed. In two cases of considering the electromagnetic excitation torque and without considering the electromagnetic excitation torque, the responded vibration of electric propulsion shafting is calculated. The low noise design of the motor and propulsion shafting provides a theoretical basis.
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Xu, Xiang, and Rui Ping Zhou. "Research on Torsional Vibration of Gear-Shafting System Based on an Extended Lumped Parameter Model." Advanced Materials Research 143-144 (October 2010): 487–92. http://dx.doi.org/10.4028/www.scientific.net/amr.143-144.487.
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In this paper, gear-shafting system dynamics theory has been introduced into the torsional vibration calculation of the marine propulsion shaft and the vibration equations of a marine gear-shafting system were established using the lumped parameter model by taking the gear-shafting system in marine propulsion shaft as the research object. In order to solve the problem of vibration equation, dynamic simulation has been done in MATLAB software, in which the natural frequency of the system has been obtained from the simulation curve by changing the input frequency, meanwhile, the conclusion that the gears pair comprehensive meshing error is independent of the system natural frequency has been achieved. Thus, the analysis method presented in this work is available for the torsional vibration calculation of the marine gear-shafting system.
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Li, Miao-Miao, Liang-Liang Ma, Chuan-Guo Wu, and Ru-Peng Zhu. "Study on the Vibration Active Control of Three-Support Shafting with Smart Spring While Accelerating over the Critical Speed." Applied Sciences 10, no. 17 (September 2, 2020): 6100. http://dx.doi.org/10.3390/app10176100.
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Smart Spring is a kind of active vibration control device based on piezoelectric material, which can effectively suppress the vibration of the shaft system in an over-critical state, and the selection of control strategy has great influence on the vibration reduction effect of the Smart Spring. In this paper, the authors investigate the control of the over-critical vibration of the transmission shaft system with Smart Spring, based on the ADAMS and MATLAB joint simulation method. Firstly, the joint simulation model of three-support shafting with Smart Spring is established, and the over-critical speed simulation analysis of the three-support shafting under the fixed control force of the Smart Spring is carried out. The simulation results show that the maximum vibration reduction rate is 71.6%. The accuracy of the joint simulation model is verified by the experiment of the three-support shafting subcritical vibration control. On this basis, a function control force vibration control strategy with time-varying control force is proposed. By analyzing the axis orbit of the shafting, the optimal fixed control force at different speeds is obtained, the control force function is determined by polynomial fitting, and the shafting critical crossing simulation under the function control force is carried out. The simulation results show that the displacement response of the shafting under the function control force is less than that under the fixed control force in the whole speed range.
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Huang, Hanlin, Shengping Fu, and Shanming Luo. "Analysis of the Influence of Transmission Housing Elasticity on the Vibration Characteristics of Gear Shafting under Coupling Effect." Shock and Vibration 2021 (December 29, 2021): 1–17. http://dx.doi.org/10.1155/2021/9623119.
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The influences of transmission housing elastic deformations on the vibration gear shafting characteristics are studied. The vibration model of the vehicle transmission system in consideration of the dynamics coupling of the housing and the gear shafting is constructed. Aiming at a vehicle transmission, the mathematical model of the bending and torsional gear shafting vibrations is established based on the lumped mass method. Following the elastic treatment of the box, a comprehensive stiffness model at the bearing considering the housing deformation is proposed to achieve the dynamic coupling between the box and the gear shafting system. Furthermore, the gear shafting vibration characteristics considering housing deformations are obtained by integrating multisource dynamic excitation, which is solved using an iterative method. The results are verified through a bench test. And, it shows that the elastic deformation of the housing aggravates the gear shafting vibration (bending and torsional coupled vibration). The peak frequency mostly remains the same. The maximum speed changes amplitude and associated root mean square value (calculated at the gear position) increase by 55.5% and 59.6%, respectively. Next, the maximum bearing support force and its root mean square value are increased by 63.7% and 97.6%, respectively. Finally, the largest increase in maximum vibration acceleration at the measuring point and the simulated root mean square value are 90% and 63.1%, respectively. It is concluded that the research results provide a theoretical basis for the study of transmission dynamic reliability.
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Nikolaidis, Efstratios, Anastassios N. Perakis, and Michael G. Parsons. "Probabilistic Torsional Vibration Analysis of a Motor Ship Propulsion Shafting System: The Input-Output Problem." Journal of Ship Research 31, no. 01 (March 1, 1987): 41–52. http://dx.doi.org/10.5957/jsr.1987.31.1.41.
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A probabilistic approach to the torsional vibration analysis of a marine diesel engine propulsion shafting system is developed. The diesel engine and propeller torsional excitation are modeled probabilistically. The statistical properties of the resulting torsional vibratory shear stress in each element of the shafting system are determined by solving the corresponding input-output problem. The shafting system is considered as a multi-input linear system with the propeller and the cylinder torsional excitation as inputs and the torsional vibratory stress as the output. Under the assumption that the nonresonant torsional vibratory stresses are negligible compared with those in resonance, the input-output problem reduces to determining the statistical properties of the output of a multi-input, linear, time-invariant system driven by Gaussian amplitude modulated (AM) processes with equal carrier frequencies. The problem is solved in its general form by deriving an expression relating the double Fourier transform of the output autocorrelation function with the double Fourier transform of the input autocorrelation and cross-correlation functions. The probabilistic approach is applied to calculate the stress statistics in each shafting element of existing low-speed and medium-speed diesel engine propulsion shafting systems.
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Xu, Deshui, Jingtao Du, and Chuan Tian. "Vibration Characteristics and Power Flow Analyses of a Ship Propulsion Shafting System with General Support and Thrust Loading." Shock and Vibration 2020 (June 13, 2020): 1–13. http://dx.doi.org/10.1155/2020/3761590.
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In this paper, flexural vibration and power flow transmission of a ship propulsion shafting structure are analyzed via energy principle description in conjunction with Rayleigh–Ritz procedure, in which the shafting vibration displacement is constructed as a superposition of Fourier series and boundary-smoothing supplementary functions. Effect of the distributed bearing support and thrust loading of propulsion shafting system is considered in terms of potential energy of system Lagrangian. Numerical examples are presented to demonstrate the reliability and effectiveness of the established model by comparing results with those from finite element method. Results show that the current model can deal with the vibration analysis of ship propulsion shafting with thrust loading and distributed bearing very well. Influence of boundary restraints, stiffness of distributed bearings, and thrust loading on vibration characteristics of ship shafting system is studied and addressed. Numerical study on power flow analysis is also conducted to investigate the characteristics of vibrational energy transmission in such practical structure. Results show that the stiffness of spatial bearing support has significant influence on vibrational energy transmission and thrust force will greatly affect the total input power into such structure.
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Shi, Zhenyi, Tao Sun, Yingzhuo Liu, Xinyu Yang, and Wei Li. "Research on key process parameters and characteristic vibration of steam turbine shafting." Journal of Physics: Conference Series 2658, no. 1 (December 1, 2023): 012060. http://dx.doi.org/10.1088/1742-6596/2658/1/012060.
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Abstract Steam turbines are a major source of vibration and noise when submarines are working. How to improve the technological level of steam turbines and reduce the vibration generated by them so that submarines can achieve the purpose of acoustic stealth has always been a hot topic of research. However, blindly improving the overall technological level of steam turbines will not only increase the manufacturing cost but also prolong the manufacturing cycle of submarines. Therefore, this paper makes a reasonable model of each type of process parameter for a certain type of steam turbine design drawings for ships. Subsequently, a dynamic model of the steam turbine shafting based on the transfer matrix was established, and experiments were designed on five groups of design parameters with strong vibration sensitivity of the steam turbine shafting. The vibration response calculation under multiple process parameters of the steam turbine shafting was carried out in combination with the two. The connection between the key process parameters of the steam turbine shafting and the characteristic vibration was established, and the influence mechanism of the key process parameters of the steam turbine shafting on the characteristic vibration was analyzed.
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Dong, Liang-xiong, Yi-ran Shi, and Shao-hua Wang. "Research on Rub-Impact Loads Response of Ship Shafting." Polish Maritime Research 25, s2 (August 1, 2018): 85–91. http://dx.doi.org/10.2478/pomr-2018-0078.
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Abstract The anti-impact ability of shafting affects stability and security of the ship power transmission directly. Moreover, it also cannot be ignored that the rub-impact loads have influence on the torsion vibration of ship shafting. In order to solve the problem of engineering application of reliability assessment under rub-impact loads, a test rig with rubbing generator is established. By carrying out the integrative analysis, the torsional vibration characteristics, such as vibration amplitude and orbit of axle center under the rub impact load are studied. According to the rub-impact conditions obtained through numerical simulation, the experimental verification is carried out on the test rig with rubbing generator. The results show that it is not obvious the influence of rub-impact loads upon the shafting torsion vibration except in special working conditions, that can be simulated by the rubbing generator. The maximum amplitude of torsional vibration is influenced by the radial rigidity as well as the friction coefficient of rubbing body, and the degree of influence is difference under conditions of continuous rubbing and serious rubbing. By adjusting the rigidity of stern bearing, the influence of rub-impact upon shafting can be weaken, which provides a theoretical reference for the safety evaluation of ship shafting.
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Zhang, Ganbo, Yao Zhao, Tianyun Li, and Xiang Zhu. "Propeller Excitation of Longitudinal Vibration Characteristics of Marine Propulsion Shafting System." Shock and Vibration 2014 (2014): 1–19. http://dx.doi.org/10.1155/2014/413592.
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The submarine experiences longitudinal vibration in the propulsion shafting system throughout most of run. A transfer matrix model of the propulsion shafting system, in which the dynamic characteristics of oil film within thrust bearing are considered, is established to describe the dynamic behavior. Using hydrodynamic lubrication theory and small perturbation method, the axial stiffness and damping of oil film are deduced in great detail, followed by numerical estimation of the foundation stiffness with finite element method. Based upon these values of dynamic parameters, the Campbell diagram describing natural frequencies in terms of shafting rotating speeds is available, and the effect on the 1st natural frequency of considerable variations in thrust bearing stiffness is next investigated. The results indicate that the amplitude of variation of the 1st natural frequency in range of low rotating speeds is great. To reduce off-resonance response without drastic changes in propulsion shafting system architecture, the measure of moving thrust bearing backward is examined. The longitudinal vibration transmission through propulsion shafting system results in subsequent axial excitation of hull; the thrust load acting on hull is particularly concerned. It is observed that the measures of structural modification are of little benefit to minimize thrust load transmitted to hull.
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Karni, Z. H., M. G. Parsons, and Z. P. Mourelatos. "Time-Varying Behavior of a Statically Indeterminate Shafting System in a Hydrodynamic Journal Bearing." Journal of Tribology 109, no. 1 (January 1, 1987): 115–23. http://dx.doi.org/10.1115/1.3261302.
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A new direct iterative method for obtaining the time-varying behavior of a statically indeterminate shafting system within one of its hydrodynamic journal bearings is described. A modified Newmark’s method is used to step in time. At each integration time step an optimization technique iterates between the shafting system and the oil film analyses until an equilibrium is achieved. The three-dimensional shafting system structural analysis and the two-dimensional oil film hydrodynamic analysis utilize the finite element method. The “hourglass control” method is employed for the construction of the oil film fluidity matrix. A numerical example illustrates the method.
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Gao, Tian Hong. "The Basic Principle of Centering of Shafting." Advanced Materials Research 971-973 (June 2014): 777–80. http://dx.doi.org/10.4028/www.scientific.net/amr.971-973.777.
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this paper focuses on researching on basic theory of shafting alignment, detailed descripting of basic assumptions by finite element method, establishment of coordinate system, finite element stiffness matrix and establishment of external constraints, providing a basic theoretical foundation in the shafting study for the future.
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Xue, Shufei, Shuochen Wu, Qing Tang, Shulin Liu, and Bai Liu. "Research on torsional vibration monitoring system of ship power shafting." IOP Conference Series: Materials Science and Engineering 1207, no. 1 (November 1, 2021): 012007. http://dx.doi.org/10.1088/1757-899x/1207/1/012007.
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Abstract In this paper, the real-time monitoring technology of ship power system torsional vibration is studied. The photoelectric non-contact measurement method is used to measure the torsional vibration intensity of shafting, and the analysis service network management platform is established to realize the functions of real-time monitoring of shafting torsional vibration and upload and collect alarm data, through the front-end system, the torsional vibration strength and other parameters of the shafting are collected and transmitted to the background. The data of the background system is used to calculate and analyze, and the status of the shafting is alarmed. The system realizes continuous monitoring and data recording of torsional vibration index of ship power system, and ensures the operation performance and safe operation of ship power system. It provides theoretical and technical support for the future development of new technologies and related research, such as durability simulation and durability virtual test of ship power critical parts.
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Gibson, J. Hamilton. "TORQUE OF PROPELLER SHAFTING." Journal of the American Society for Naval Engineers 19, no. 2 (March 18, 2009): 415–29. http://dx.doi.org/10.1111/j.1559-3584.1907.tb02469.x.
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Zhao, Yan, Fei Gao, Yulei Xia, Jinfang Gu, Yameng Wang, and Sen Zhao. "Analysis on the Dynamic Behavior of Space Shafting under Combined Load." Shock and Vibration 2024 (January 13, 2024): 1–12. http://dx.doi.org/10.1155/2024/5560548.
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The space shafting is the core component of the momentum exchange attitude control actuator for spacecraft.The dynamic behavior of space shafting has an important impact on the performance of the actuators. Based on the dynamic theory of rolling bearing, this paper presents a dynamic analysis model of space shafting for the interaction between bearing balls and oil-containing nonmetallic cage under combined loads. Also, the accuracy of the analysis model was verified through a high-speed camera system to conduct a cage speed test. In addition, the dynamic behavior of balls and cage under combined loads and the interaction between them is also analysed. The results show that the axial displacements of balls fluctuate periodically under combined loads, and the rotation speeds of balls and cage are easily affected by the load, presenting as the oscillation of speed. Also, the force between balls and cage increases as the load increases. The dynamic behavior of balls and cage could be effectively improved by avoiding excessive torque loads and limiting the axial preload to 40 N. The wear failure caused by unstable operation of bearings cannot be ignored. This model is more practical in completing simulation analysis of different operating conditions and structural parameters of the shafting system. It provides a theoretical reference for the structural design and performance analysis of space shafting.
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Kushner, Guriy Alekseevich, and Victor Andreevich Mamontov. "Estimating efficiency of forecasting technical conditions of ship propulsion systems." Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies 2021, no. 4 (November 30, 2021): 27–33. http://dx.doi.org/10.24143/2073-1574-2021-4-27-33.
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The article considers an approach to assessing the effectiveness of the most common methods of predicting the technical conditions and failure with reference to the ship shafting. There have been analyzed the main factors in operation of the ship shaft line, which cause the change in its technical state. It has been found that a special feature of some loads acting on the propeller shaft is their stochastic or changing nature over time, which hampers predicting the technical state of the shafting and its units. The features of stochastic and extrapolation forecasting methods have been analyzed. The possibility of using statistical methods in conditions of mass standard production of shafting units with a relatively short regulated service life is estimated. An extrapolation method is proposed for predicting the maximum permissible clearance of stern tube bearings. The case of accumulating samples of measuring results of the propeller shaft sagging in the given time intervals is considered, the approximating functions are constructed. The criteria for the reliability of the results of extrapolation methods for predicting the wear of stern tube bearings are determined. There have been developed the proposals for adapting the causal method as an alternative to the extrapolation method. A schematic diagram of a system for the ship shafting failure predicting has been developed using the registration and analysis of vibration parameters, which serves as the basis for constructing a regression model of damage accumulation. The proposed forecasting system allows studying the actual operating conditions of the shafting, defining the actual external loads and the regularities of their occurrence, measuring deformations and stresses, and determining quantitative indicators of the reliability of the shafting during normal operation and special operating modes, for example, with vibration resonance. The theoretical basis of the algorithm for calculating and registering loads affecting the service life of shafts is proposed.
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Wang, Fei, Jianbin Liao, Chaoming Huang, Hanlin Li, Jiayu Cao, Hongliang Yu, and Jin Yan. "Testing and Analysis of Torsional Vibration of Ship Transmission Shafting Based on Five-Point Smoothing Algorithm." Processes 10, no. 9 (September 5, 2022): 1790. http://dx.doi.org/10.3390/pr10091790.
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In this paper, a method is proposed to accurately measure the torsional vibration of a ship’s propulsion shafting, and calculate its instantaneous torque based on instantaneous speed data. The instantaneous speed signal of a ship is measured by a data acquisition instrument indirectly under the deceleration condition, and then filtered by the five-point smoothing algorithm. The filtered instantaneous speed signal is further processed to calculate the maximum amplitude of the torsional vibration, along with the maximum torque of the propulsion shafting under specific operating conditions. The proposed method can effectively improve the calculation accuracy of the torsional vibration of the shafting, and provides reliable theoretical basis for setting the safe speed of the ship’s diesel engine.
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Wen, Xiao Fei, Xing Di Wang, and Qiang Yuan. "A Study on Test Technology of Ship Shafting Torsional Vibration." Advanced Materials Research 199-200 (February 2011): 1423–28. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.1423.
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Ship shafting is a key component of ship power plant. Torsional vibration test for ship shafting is the essential step to ensure the safety of ship power systems. For the purpose of analyzing and comparing torsional vibration test methods, a study of the test methods, equipment and technology is carried out in this paper. Three different test methods are compared with each other by adopting two different test systems. The main propulsion and marine generator shafting torsional vibration characteristics are analyzed by using two different analysis methods respectively: the single order and resonance point method and the multi order and resonance point method. The results obtained in the process of testing on board ship may provide a good guidance for the further researches in this subject.
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Li, Miaomiao, Zhuo Li, Liangliang Ma, Rupeng Zhu, and Xizhi Ma. "Effect of the Supports’ Positions on the Vibration Characteristics of a Flexible Rotor Shafting." Shock and Vibration 2020 (February 12, 2020): 1–11. http://dx.doi.org/10.1155/2020/1592794.
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In this study, we evaluated the effect of changing supports’ position on the vibration characteristics of a three-support flexible rotor shafting. This dependency was first analyzed using a finite element simulation and then backed up with experimental investigations. By computing a simplified rotor shafting model, we found that the first-order bending vibration in a forward whirl mode is the most relevant deforming mode. Hence, the effect of the supports’ positions on this vibration was intensively investigated using simulations and verified experimentally with a house-made shafting rotor system. The results demonstrated that the interaction between different supports can influence the overall vibration deformation and that the position of the support closer to the rotor has the greatest influence.
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Liu, Lei, WeiWei Jiang, and Bi He. "Analysis and Experimental Research on Dynamic Characteristics of Horizontal Shaft System of Photoelectric Equipment." Journal of Physics: Conference Series 2396, no. 1 (December 1, 2022): 012008. http://dx.doi.org/10.1088/1742-6596/2396/1/012008.
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Abstract In order to study the transmission characteristics of vibration in the shafting of optoelectronic equipment, a horizontal shafting test platform for optoelectronic equipment is designed. Firstly, according to the special structure and load conditions of the three-row ball-column combined turntable bearing used in the horizontal shafting, a quasi-static model of the bearing load was established to solve the load distribution of the bearing and further calculate the bearing stiffness. At the same time, the bearing system was established. The dynamic model of the system is used to calculate the frequency response function of the system under the conditions of radial load and axial load and analyze the vibration transmission characteristics of the shaft system. Based on the finite element method, a finite element calculation model is established, the shafting dynamic model established is used to simplify the bearing, the modal parameters of the equipment are analyzed, and the experimental verification is carried out using the Siemens dynamic test system. The results show that the established model is effective and reliable. It provides a reference for studying the dynamic characteristics of the shaft system of optoelectronic equipment.