Artigos de revistas: "Bearing flexibility"

1

OHTA, Hiroyuki, e Shoji YASUMOTO. "Ball Bearing Stiffness Incorporating Bearing Ring Flexibility." Transactions of the Japan Society of Mechanical Engineers Series C 67, n.º 660 (2001): 2643–50. http://dx.doi.org/10.1299/kikaic.67.2643.

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Jakobs, T., G. Jacobs, J. Euler, A. Rolink e J. Röder. "Impact of 3D segment profiling on friction losses of plain bearings in wind turbines main bearings". Journal of Physics: Conference Series 2767, n.º 5 (1 de junho de 2024): 052021. http://dx.doi.org/10.1088/1742-6596/2767/5/052021.

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Abstract Wind power is a crucial technology in transitioning to a carbon-free energy future. To increase the economic competitiveness, the levelized cost of electricity of wind power needs to be further reduced. A critical factor contributing to maintenance expenses is the failure of main rolling bearings. Replacing these rolling bearings in the case of damages is a costly procedure as it necessitates dismantling the wind turbine drivetrain. Unlike conventional rolling bearings, segmented plain bearings allow for the up-tower replacement of individual faulty segments, significantly reducing downtime and maintenance costs. The FlexPad plain bearing concept specifically addresses the need for an easy-to-maintain main bearing for wind turbines. While the current FlexPad design guideline focuses on global geometrical parameters disregarding a detailed segment profile optimization, literature suggests that a 3D-profile on the segments can enhance bearing performance by reducing frictional losses. However, the investigations conducted in literature were limited to stationary thrust bearings. The FlexPad bearing's inherent flexibility and conical shape preclude direct application of the findings in literature. Therefore, a coupled elastohydrodynamic-multi-body simulation model was developed to account for the bearing's flexibility while investigating different 3D-profiles. This study quantifies the impact 3D-profiles on friction power, solid contact, and maximum hydrodynamic pressure, demonstrating the advantages. The best 3D-profiles achieve a decrease in friction power of 18.3% with an increase of the maximum hydrodynamic pressure of just 4.9%.

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3

Thomsen, Kim, e Peder Klit. "Improvement of journal bearing operation at heavy misalignment using bearing flexibility and compliant liners". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 226, n.º 8 (1 de março de 2012): 651–60. http://dx.doi.org/10.1177/1350650112439372.

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A flexure journal bearing design is proposed that will improve operational behaviour of a journal bearing at pronounced misalignment. Using a thermoelastohydrodynamic model, it is shown that the proposed flexure journal bearing has vastly increased the hydrodynamic performance compared to the stiff bearing when misaligned. The hydrodynamic performance is evaluated on lubricant film thickness, pressure and temperature. Furthermore, the influence of a compliant bearing liner is investigated and it is found that it increases the hydrodynamic performance when applied to a stiff bearing, whereas the liner has practically no influence on the flexure journal bearing's performance.

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4

Liu, Xiangyang, Rongjun Niu, Bin Wang, Shuai Zhang, Yongcun Cui e Zhanli Zhang. "Crowning Method on Bearing Supporting Large Wind Turbine Spindle Considering the Flexibility of Structure of Shaft System". Machines 11, n.º 1 (26 de dezembro de 2022): 28. http://dx.doi.org/10.3390/machines11010028.

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To meet the precision design of bearings on large wind turbine spindles, a crowning method of bearing on wind turbine spindles considering the flexibility of the support structure is proposed. Firstly, a finite element (FE) model of the shaft system with a flexible structure is constructed by connecting the shaft and bearing through constraint equations (CE) and multi-point constraint (MPC) algorithms and replacing the bearing rollers with nonlinear spring elements and dampers. Then, the Newmark integration algorithm is used to solve the model and analyze the effect of the structure’s rigidity on the load distribution of bearings. Then, perform convergence analysis of the sequences of the spring load distribution using a high-pass filter based on fast Fourier transform (FFT) and root mean square error (RMSE) to obtain a suitable number of replacement springs. Finally, a sub-model of the upwind bearing is constructed with structured mesh. With the maximum Von Mises stress of the roller profile as the design target, the optimal logarithmic crowning of the roller and its tolerance zone under the given working conditions are obtained. The results show that the FE model of the shaft system proposed has good convergence. The FE model of the shaft system considering the flexibility of the support structure can obtain more accurate load distributions of bearings and can make the accurate crowning design of the bearing rollers based on the actual working conditions. This provides support for the precision design of bearings in large shaft systems.

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5

Zhang, Jun Yan, Su Fen Zhang e You Wei Zhang. "The Analysis of the Deformation and Contact Lubrication Problem of HPD Diesel Engine Connecting Rod Bearings Based on the FFT Method and Flexibility Matrix Method". Advanced Materials Research 602-604 (dezembro de 2012): 2170–73. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.2170.

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Based on the fast fourier transform (FFT) and flexibility matrix method, the effects of the FFT and flexibility matrix method on the distribution of oil film pressure, elastic deformation in the steady load and the journal center orbit of the connecting rod big-end bearings in the dynamic load are investigated. The results are shown that when the eccentricity ratio is more than 1, the maximum oil film pressure obtained by FFT method is bigger on both ends of the journal bearing and on its intermediate position is smaller. To the connecting rod big-end bearing, under the dynamic load condition, there is the same trend of the journal center orbit with two methods. However, with FFT method, the journal is largely deviated from bearing center.

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Zhang, Jun Yan, Shu Kui Han, Su Fen Zhang e You Wei Zhang. "A Comparative Study of the Methods for Calculation of Journal Bearing Elastohydrodynamic Lubrication". Advanced Materials Research 594-597 (novembro de 2012): 2727–30. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.2727.

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Based on the fast fourier transform（FFT） and flexibility matrix method, the study is presented for journal bearing elastohydrodynamic lubrication. The effects of FFT and flexibility matrix method on the distribution of oil film pressure and elastic deformation in the steady load are investigated. The results are shown that the difficulty of the EHL for journal bearings in the case of high eccentricity ratios or heave loads can be effectively solved by the FFT method. When the eccentricity ratio is smaller, the magnitude and distribution of the oil film pressure are basic agreement by FFT method and flexibility matrix method. When the eccentricity ratio enhances, the maximum oil film pressure obtained by FFT method is bigger on both ends of the journal bearing and on its intermediate is smaller.

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7

Мединський, Валерій Володимирович, e Дмитро Миколайович Зінченко. "Influence of the aircraft bearing surface flexibility on its bearing properties". Information systems, mechanics and control, n.º 20 (30 de junho de 2019): 29–40. http://dx.doi.org/10.20535/2219-3804202019194412.

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8

Earles, L. L., A. B. Palazzolo e R. W. Armentrout. "A Finite Element Approach to Pad Flexibility Effects in Tilt Pad Journal Bearings: Part II—Assembled Bearing and System Analysis". Journal of Tribology 112, n.º 2 (1 de abril de 1990): 178–82. http://dx.doi.org/10.1115/1.2920239.

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Pad flexibility effects are studied in an actual bearing. This flexibility is shown to decrease the predicted instability onset speed of the rotor bearing system. The use of complex eigenvalue dependent bearing coefficients as compared with using synchronously reduced coefficients is seen to produce a more significant decrease in the instability onset speed. Further reductions in the instability onset speed are obtained by including pivot stiffness in the complex eigenvalue dependent bearing coefficients.

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9

Smolnicki, Tadeusz, e Eugeniusz Rusiński. "Superelement-Based Modeling of Load Distribution in Large-Size Slewing Bearings". Journal of Mechanical Design 129, n.º 4 (29 de março de 2006): 459–63. http://dx.doi.org/10.1115/1.2437784.

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The supporting structures in large-size slewing bearings are highly flexible. In order to choose the proper bearing and shape the load-carrying structure one must estimate the distribution of forces among the individual rolling elements. Advanced numerical models are needed for this. An original method of modeling the rolling element-track system is presented and its usefulness for modeling large-size bearings is demonstrated. The results of an exemplary analysis are presented in the form of graphs and figures. The superelement-based discrete bearing models are so far most comprehensive and take into account all the phenomena involved in the bearing-supporting structures system. The application of the finite-element method and the models based on the track-rolling element-track superelement made it possible to determine the effect of the deformability of the supporting structures and the nonuniformity of their flexibility on the loading of the rolling elements in the two-row bearing. The use of formulas which do not take into account the flexibility of the supporting structures to determine the distribution of the load among the rolling elements is unacceptable.

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10

Kumar, D. Satish, C. Sujatha e N. Ganesan. "Disc flexibility effects in rotor bearing systems". Computers & Structures 62, n.º 4 (fevereiro de 1997): 715–19. http://dx.doi.org/10.1016/s0045-7949(96)00214-3.

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11

Krynke, Marek, e Alan Vaško. "Management The Safety of Exploitation of the Rotation Mechanism in a Self-Propelled Crane". System Safety: Human - Technical Facility - Environment 1, n.º 1 (1 de março de 2019): 624–31. http://dx.doi.org/10.2478/czoto-2019-0079.

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AbstractThe article analyzes of the load capacity of the rotation mechanism of the boom arm sub-assembly for a self-propelled crane. The uneven flexibility of systems supporting structures of the machine was taken into account in the identification of the load. The consideration are illustrated by the example slewing bearing from self-propelled crane. FEM method was used for calculations. The basic problems of construction of numerical model were discussed. Sample calculations of bearing carrying capacity has been done taking into account flexibility of bearings supporting structures, which also allowed to define the internal load distribution in the bearing. On example of the supporting structure of the mobile crane DST 5050 the internal load distribution in the crane bearing at different positions of the crane machine body were defined. During the rotation of the crane body priority angels were indicated. It has been shown that the deformations of the supporting frames are so large that they significantly change the distribution of forces transmitted by the individual bearing rollers.

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12

Islam, A. B. M. Saiful, Mohd Zamin Jumaat, Raja Hussain e Md Ashraful Alam. "INCORPORATION OF RUBBER-STEEL BEARING ISOLATION IN MULTI-STOREY MUILDING". Journal of Civil Engineering and Management 19, Supplement_1 (9 de janeiro de 2014): S33—S49. http://dx.doi.org/10.3846/13923730.2013.801904.

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Base isolation incorporation has moved towards a popular technology in the seismic vulnerable regions. The system mitigates lateral action of tremor hazard providing flexibility of structures. Implementing base isolation on buildings in the soil and seismic condition of medium risk seismicity is currently an important issue. A thorough investigation is of burning need for buildings to be incorporated with base isolator and to carry out dynamic analysis. The study provides incorporation of rubber-steel bearings and focuses on the structural changes. Designs of base isolation bearings are performed along with structural viability check. Lead rubber bearing (LRB) and high damping rubber bearing (HDRB) have been inserted on the corresponding structural bases. In finite-element approach, link element simulates the bearing. Bi-linear hysteretic behaviour is presented for LRB and equivalent linear model simulated HDRB. Linear static, free vibration and dynamic frequency-domain analyses are performed for both isolated and non-isolated buildings under bidirectional site-specific earthquake. The study reveals that for multi-storey buildings, isolation can drastically reduce seismic responses. Furthermore, flexibility of buildings predicts some structural savings for reduced responses. Good agreement has been achieved through rapid solution in frequency-domain approach. In medium risk earthquake-prone area, rubber-steel bearing isolators can be beneficially inserted.

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13

Dmochowski, Waldemar. "Dynamic Properties of Tilting-Pad Journal Bearings: Experimental and Theoretical Investigation of Frequency Effects due to Pivot Flexibility". Journal of Engineering for Gas Turbines and Power 129, n.º 3 (1 de setembro de 2006): 865–69. http://dx.doi.org/10.1115/1.2436574.

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Tilting-pad journal bearings (TPJBs) dominate as rotor supports in high-speed rotating machinery. The paper analyzes frequency effects on the TPJB’s stiffness and damping characteristics based on experimental and theoretical investigations. The experimental investigation has been carried out on a five pad tilting-pad journal bearing of 98mm in diameter. Time domain and multifrequency excitation has been used to evaluate the dynamic coefficients. The calculated results have been obtained from a three-dimensional computer model of TPJB, which accounts for thermal effects, turbulent oil flow, and elastic effects, including that of pad flexibility. The analyzes of the TPJB’s stiffness and damping properties showed that the frequency effects on the bearing dynamic properties depend on the operating conditions and bearing design. It has been concluded that the pad inertia and pivot flexibility are behind the variations of the stiffness and damping properties with frequency of excitation.

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14

Dang, Phuoc Vinh, Steven Chatterton e Paolo Pennacchi. "The Effect of the Pivot Stiffness on the Performances of Five-Pad Tilting Pad Bearings". Lubricants 7, n.º 7 (22 de julho de 2019): 61. http://dx.doi.org/10.3390/lubricants7070061.

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The role of the pivot flexibility in tilting-pad journal bearings (TPJBs) has become essential, particularly for bearings working at high applied load and relatively high rotor speeds. Predictions from a simple bearing model with rigid pivots show incorrect estimation of the dynamic coefficients in comparison with the experimental results. Normally, the more flexible the pad pivot, the lower the dynamic coefficients because the stiffness of the pivot takes in series with the stiffness and damping of the oil film. This paper investigates the influence of pivot stiffness on the dynamic force coefficients of two different five-pad TPJBs as a function of the applied static load and excitation frequency: rocker-backed pivot and spherical pivot bearings. In order to highlight the effect of the pivot stiffness in the spherical pivot bearing, displacement restriction components and elastic copper made shims have been used. Firstly, a thermo-elasto-hydrodynamic model for the static and dynamic characteristics of the two bearings is described. This model takes into account the flexibility of both pad and pivot. The pivot stiffnesses calculated by means of the Hertz theory and those obtained by experiments have been introduced and compared in the model. The clearance profiles of two tested bearing and the shaft center loci obtained by measurement and prediction are also shown. The dynamic coefficients of the two bearings obtained from the numerical simulation were compared with the experimental results. By the analysis it can be concluded that the effect of the pivot flexibility on the clearance profile, the shaft locus and on the dynamic coefficients is very significant. More important, it is important to estimate the pivot stiffness of each single pad using experimental measurements.

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15

Kulkarni, Jeevan A., e R. S. Jangid. "Effects of Superstructure Flexibility on the Response of Base-Isolated Structures". Shock and Vibration 10, n.º 1 (2003): 1–13. http://dx.doi.org/10.1155/2003/368693.

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A parametric study of base-isolated structure with different isolation systems is conducted for investigating the effects of superstructure flexibility. The superstructure is idealized as a one-storey structure isolated by different systems such as elastomeric bearings (with and without lead core) and sliding systems. The governing equations of motion of the isolated structural system are derived and the response of the system is obtained for stochastic model of earthquake ground motion. The earthquake ground motion is modeled as a uniformly modulated non-stationary random process. The stochastic response of isolated structure is obtained using the state variable approach. An equivalent linearization technique is used for the approximate response of isolated structure with non-linear isolation systems. The mean square superstructure acceleration and bearing displacement of the system are plotted under different system parameters and compared with the corresponding response of rigid sup erstructure condition to study the influence of superstructure flexibility. The comparison of response is made under various isolation system parameters (i.e. isolation period, damping, yield strength of elastomeric bearings and friction coefficient of sliding systems). It is observed that the bearing displacement can accurately obtained by modelling the superstructure as a rigid body in a base-isolated structure. However, such approximation may under-estimates the superstructure acceleration under certain conditions.

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16

Yao, Tingqiang, Yilin Chi e Yayu Huang. "Research on Flexibility of Bearing Rings for Multibody Contact Dynamics of Rolling Bearings". Procedia Engineering 31 (2012): 586–94. http://dx.doi.org/10.1016/j.proeng.2012.01.1071.

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17

Chen, Y. S., H. Y. Wu e P. L. Xie. "Stability of Multirecess Hybrid-Operating Oil Journal Bearings". Journal of Tribology 107, n.º 1 (1 de janeiro de 1985): 116–21. http://dx.doi.org/10.1115/1.3260986.

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An analysis and a numerical solution using finite difference method to predict the dynamic performance of multirecess hybrid-operating oil journal bearings are presented. The linearized stiffness and damping coefficients of a typical capillary-compensated bearing with four recesses are computed for various design parameters. The corresponding stiffness and the stability threshold of the bearing are then obtained, and the opposite influences of the hydrodynamic action on them are demonstrated. The effect of rotor flexibility on the onset of self-excited whirl is discussed, and a method is given to determine the stability threshold of a rotor-hybrid bearing system.

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18

Rezaei, Ashkan, Florian Schleich, Oliver Menck, Matthis Grassmann, Arne Bartschat e Amir R. Nejad. "Comparative analysis of rolling contact fatigue life in a wind turbine pitch bearing with different modeling approaches". Journal of Physics: Conference Series 2767, n.º 5 (1 de junho de 2024): 052036. http://dx.doi.org/10.1088/1742-6596/2767/5/052036.

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Abstract The load calculation for wind turbines usually does not take pitch bearings into account, and the pitch-bearing internal load distribution is calculated in a decoupled process. In the current study, a coupled wind turbine load simulation considering the pitch bearings is proposed. Internal pitch-bearing load distribution and roller contact fatigue life are compared to a decoupled approach using a high-fidelity finite-element model. Internal pitch-bearing load distribution can be an essential variable in almost all major pitch-bearing failures. Furthermore, rolling contact fatigue is one of the major types of pitch-bearing failure that can represent the bearing service life. The results show that the flexibility of the surroundings has an effect on the contact forces. As a result, the finite element model-based life calculation of the NREL 5 MW turbine predicts a longer rolling contact fatigue life for the bearing than the multi-body system-based one. For the IWT7.5, sample load cases indicate that this behavior is different, leading to the conclusion that the life of the bearing is significantly affected by the stiffness of the bearing and its surrounding components.

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Casanueva, C., A. Alonso e J. G. Giménez. "Influence of Bearing Flexibility in Rail Vehicle Dynamics". International Journal of Railway Technology 4, n.º 1 (2015): 47–67. http://dx.doi.org/10.4203/ijrt.4.1.3.

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20

Lin, C. R., e H. G. Rylander. "Performance Characteristics of Compliant Journal Bearings". Journal of Tribology 113, n.º 3 (1 de julho de 1991): 639–44. http://dx.doi.org/10.1115/1.2920672.

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This investigation of compliant journal bearings is directed toward the fundamental behavior characteristics which are necessary when compliance is factored into the final design. Analytical determintation of performance characteristics are shown as a function of the bearing flexibility. As the deformation coefficient increases, load capacity decreases, the cavitation angle and friction coefficient increase, attitude angle may increase or decrease, stability is improved for attitude angles less than 0.8, and minimum film thickness will occur near the two sides of the bearing.

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21

Hagemann, Thomas, Huanhuan Ding, Esther Radtke e Hubert Schwarze. "Operating Behavior of Sliding Planet Gear Bearings for Wind Turbine Gearbox Applications—Part II: Impact of Structure Deformation". Lubricants 9, n.º 10 (1 de outubro de 2021): 98. http://dx.doi.org/10.3390/lubricants9100098.

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The use of planetary gear stages intends to increase power density in drive trains of rotating machinery. Due to lightweight requirements on this type of machine elements, structures are comparably flexible while mechanical loads are high. This study investigates the impact of structure deformation on sliding planet gear bearings applied in the planetary stages of wind turbine gearboxes with helical gears. It focuses on three main objectives: (i) development of a procedure for the time-efficient thermo-elasto-hydrodynamic (TEHD) analysis of sliding planet gear bearing; (ii) understanding of the specific deformation characteristics of this application; (iii) investigation of the planet gear bearing’s modified operating behavior, caused by the deformation of the sliding surfaces. Generally, results indicate an improvement of predicted operating conditions by consideration of structure deformation in the bearing analysis for this application. Peak load in the bearing decreases because the loaded proportion of the sliding surface increases. Moreover, tendencies of single design measures, determined for rigid geometries, keep valid but exhibit significantly different magnitudes under consideration of structure deformation. Results show that consideration of structure flexibility is essential for sliding planet gear bearing analysis if quantitative assertions on load distributions, wear phenomena, and interaction of the bearing with other components are required.

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Nikolajsen, J. L. "The Effect of Misalignment on Rotor Vibrations". Journal of Engineering for Gas Turbines and Power 120, n.º 3 (1 de julho de 1998): 635–40. http://dx.doi.org/10.1115/1.2818193.

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Rotors with three or more fluid-film bearings (or fluid seals) have “redundant” supports, and, therefore, interdependent bearing loads that are generally unknown both in magnitude and direction. The steady-state bearing eccentricities and the dynamic stiffness and damping coefficients of the bearings are, therefore, also unknown since both are functions of the bearing loads. Thus, the dynamic behavior of multibearing rotors generally cannot be predicted with good accuracy without access to a procedure for calculating the steady-state bearing loads and eccentricities. This paper outlines such a procedure in terms of both the influence coefficient method, the transfer matrix method, and the finite element method. Radial bearing misalignment and flexibility of the bearing back-up structures are accounted for. Once the eccentricities are available, the bearing stiffness and damping coefficients can be calculated in the usual way and used to predict critical speeds, instability threshold speed, and rotor response to imbalance. A numerical example is presented that illustrates some of the nonlinear effects of bearing support redundancy, notably the large variations in instability threshold speed with radial bearing misalignment. The example shows how the method can be used to determine the level of bearing misalignment that leads to optimum rotor stability. It is concluded that no simple guide lines exist by which optimum stability can be achieved. Neither perfect bearing alignment nor equal load sharing between bearings necessarily lead to optimum stability.

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Zhang, Xinyue, Gang Wang, Daqi Wu, Jian Guan e Wenjie Chen. "Contact Load and Elastohydrodynamic Lubrication Analysis of Eccentric Bearings in RV Reducer Considering the Effects of Roller Profile Modification". Lubricants 13, n.º 1 (3 de janeiro de 2025): 14. https://doi.org/10.3390/lubricants13010014.

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The mechanical and tribological behavior of eccentric bearings is crucial for the performance of a RV reducer. By combining the finite element model (FEM) and the elastohydrodynamic lubrication (EHL) method, a comprehensive model for the cylindrical roller bearings applied in the RV reducer is developed in this study. During the modeling phase, FEM is utilized to determine the bearing load, taking into account the structural flexibility. The FEM result demonstrates that a 15% increase in the maximum bearing’s load is detected by the FEM compared to the analytical model. After the simulations, the effects of the roller profile modification, the bearing load and the rolling speed on the bearing performance are revealed. The numerical results indicate that the combined generatrix shape roller results in weaker edge effects and stress concentration compared with that of the straight generatrix shape roller and the arc generatrix shape roller. The optimal values of modification length and modification quantity under various load and rolling speed conditions are provided. Furthermore, durability tests on RV reducers equipped with the three types of rollers were conducted. Experimental outcomes demonstrate that the combined generatrix shape roller significantly improves the reliability and fatigue life of the RV reducer, corroborating the numerical analyses.

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Karimaei, Hadiseh, e H. R. Chamani. "Effect of Crankshaft and Crankcase Material Stiffness on Load Distribution in Main Bearings". International Journal of Automotive and Mechanical Engineering 15, n.º 4 (24 de dezembro de 2018): 5941–56. http://dx.doi.org/10.15282/ijame.15.4.2018.16.0453.

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In multi-cylinder diesel engines, hydrodynamic pressure distribution of main bearings has significant effect on the load distribution applied on engine crankcase, therefore, has an effect on the stress distribution and deflection of crankcase. Flexibility of crankshaft and crankcase assembly has significant effect on load distribution in engine main bearings. In this paper, the effect of elastic deformations of both crankshaft and crankcase on the load distribution in the main bearings is studied. Considering deformations of crankcase and crankshaft together with the elasto-hydrodynamic (EHD) analysis of main bearing is vital to obtain the realistic load distribution and accurate main bearing performance. At the beginning, the results of flexible body dynamic analysis of engine crank train with considering EHD joint for main bearings are presented and the main bearing force and moment are compared with rigid body dynamic analysis. Then, the effects of crankshaft and crankcase flexibilities on main bearing force and moment are studied. Several models with different flexibilities and stiffness of crankcase and crankshaft were prepared using Elasto-hydrodynamic simulation of diesel engine main bearings. According to the results, the load distribution on the engine main bearings and consequently the bearing shell deformation are affected by crankcase and crankshaft elasticities. A fast and time-saving method to obtain reasonably accurate results is proposed in the present paper.

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Kunz, Peter C., Markus Börgardts e Fabian Mohr. "Structural flexibility in complexes bearing a tripodal nitrogen ligand". Inorganica Chimica Acta 380 (janeiro de 2012): 392–98. http://dx.doi.org/10.1016/j.ica.2011.11.011.

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Pei, Tianyi, Hengliang Zhang, Wei Hua e Fengyu Zhang. "Comprehensive Review of Bearing Currents in Electrical Machines: Mechanisms, Impacts, and Mitigation Techniques". Energies 18, n.º 3 (23 de janeiro de 2025): 517. https://doi.org/10.3390/en18030517.

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The present paper deals with a review on bearing currents in electrical machines, with major emphasis on mechanisms, impacts, and mitigation strategies. High-frequency common-mode voltages from the inverter-driven system have been found to be the main reason for bearing current leading to motor bearing degradation and eventual failure. This paper deals with bearing currents—electrical discharge machining (EDM) currents, circulating bearing currents, and rotor-to-ground bearing currents—and the various methods of their generation and effects that are harmful to the bearings and lubricants of a motor. Mitigation techniques, among which the following have been taken into account, are studied in this context: the optimization of PWM modulation, and the use of shaft grounding brushes, insulated bearings, and passive or active filters. Finally, advantages, limitations, and implementation challenges are discussed. A review comparing three-phase and dual three-phase inverters showed that, due to the increased degree of freedom in modulation strategies, it is possible to eliminate common-mode voltages through active modulation techniques. Such added flexibility will reduce the risk of bearing currents effectively. It also highlights future research directions in bearing current suppression, including the development of multi-phase motor systems, real-time monitoring technologies with artificial intelligence, and the use of new insulation materials for the enhancement of bearing reliability. The results obtained should guide future research and engineering practices in suppressing bearing currents to improve motor durability with high performance.

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Youcef-Toumi, K., e S. Reddy. "Dynamic Analysis and Control of High Speed and High Precision Active Magnetic Bearings". Journal of Dynamic Systems, Measurement, and Control 114, n.º 4 (1 de dezembro de 1992): 623–33. http://dx.doi.org/10.1115/1.2897734.

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The successful operation of actively controlled magnetic bearings depends greatly on the electromechanical design and control system design. The function of the controller is to maintain bearing performance in the face of system dynamic variations and unpredictable disturbances. The plant considered here is the rotor and magnetic bearing assembly of a test apparatus. The plant dynamics consisting of actuator dynamics, rigid rotor dynamics and flexibility effects are described. Various components of the system are identified and their corresponding linearized theoretical models are validated experimentally. Tests are also run to identify the coupling effects and flexibility modes. The highly nonlinear behavior of the magnetic bearings in addition to the inherent instability of such a system makes the controller design complex. A digital Time Delay Controller is designed and its effectiveness evaluated using several simulations based on linear and nonlinear models for the bearing including bending mode effects. This controller is implemented as an alternative to an existing linear analog compensator. Several experiments are conducted with each controller for spinning and nonspinning conditions. These include time responses, closed loop frequency responses and disturbance rejection responses. The experimental results and comparisons between those of a digital Time Delay Controller and an analog compensator indicate that the Time Delay Controller has impressive static and dynamic stiffness characteristics for the prototype considered. The Time Delay Controller also maintains almost the same dynamic behavior over a significantly wide range of rotor speeds.

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Kumar, Vijay, Satish C. Sharma and e S. C. Jain. "Stability Margin of Hybrid Journal Bearing: Influence of Thermal and Elastic Effects". Journal of Tribology 126, n.º 3 (28 de junho de 2004): 630–34. http://dx.doi.org/10.1115/1.1759343.

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This paper deals with the stability margin of a constant flow valve compensated hole-entry hybrid journal bearing system considering bearing flexibility and variation of viscosity due to temperature rise of the lubricant. The journal temperature is computed on the basis of average fluid-film temperature and axisymmetric isothermal element is assumed. The coupled solution of Reynold’s, energy, conduction, and elasticity equations is obtained using finite element method. The performance of a symmetric and asymmetric hole-entry hybrid journal bearing configurations is studied. The results presented in the study indicate that the bearing flexibility and temperature rise of the lubricant fluid-film affects the performance of the hole-entry hybrid journal bearing system quite significantly and proper selection of restrictor design parameter is quite useful in maintaining the fluid film thickness and threshold speed of the journal.

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Meng, Qingguo, Zeliang Wang, Jinyao Mu e Lingchun Kong. "Development of a rotation and swing torque detection system after bearing installation". Vibroengineering Procedia 55 (27 de setembro de 2024): 169–74. http://dx.doi.org/10.21595/vp.2024.23979.

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The swing torque and rotational torque after the spherical bearing is installed directly affect the performance of the spherical bearing. At this stage, the friction torque detection equipment of the spherical bearing is mainly used to detect uninstalled bearings. A set of rotation and swing after the bearing is installed is designed. Torque detection system. The detection principles of rotational torque and swing torque required for flexibility detection were analyzed, the functional design requirements and main technical indicators of the detection system were clarified, and the overall design plan of the detection system was established; the host structure of the detection system was designed, including rotational torque detection system, swing torque detection system, clamping system and calibration system; completed the scheme design of the detection control system, selected the torque sensor and servo motor, designed the main electrical control circuit of the detector; conducted error analysis of the detector.

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30

Dong, Pu, Rongjun Niu, Yushuo Wang, Ruifang Lv, Lanlan Li e Wenchao Xie. "Study on the Influence of Plugging Position and Fit on the Motion Stability of Precision Cross Roller Bearing". Machines 12, n.º 10 (27 de setembro de 2024): 678. http://dx.doi.org/10.3390/machines12100678.

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This study addresses the issue of unsatisfactory smoothness in the movement of integrated internal and external cross roller bearings post-assembly, which compromises the movement flexibility of the finished bearing and fails to meet index requirements. Focusing on a specific type of precision cross roller bearing, this paper establishes a finite element explicit dynamic simulation model that takes into account the plugging position and matching relationship. A transient dynamic simulation of the roller blockage process was conducted, yielding insights into the contact pressure and deformation experienced by the roller and plug during this blockage. The results indicate that when both the taper pin are positioned centrally, and the plug matching clearance, plug sag and protruding amount, and plug rotation offset degrees are all set to 0 μm, the contact pressure between the roller and raceway, as well as the roller deformation displacement, are minimized. The plugging position and fit were subsequently validated through testing, which also measured the impact of these parameters on the roundness of the raceway surface and the bearing’s friction torque. The test findings corroborate that when the taper and pin are centrally aligned, and the stopper clearance is 5 μm, with the plug sag, protrusion, and offset all at 0 μm, the roundness of the raceway surface and the bearing’s friction torque reach their lowest values, thereby optimizing the stability of bearing motion. By comparing the simulation and experimental results, it is concluded that during bearing assembly, it is crucial to maintain the taper pin in a central position, control the plug matching clearance to approximately 5 μm, and ensure the plug sag, protrusion, and rotation offset amount are both at 0 μm. This approach guarantees optimal contact conditions and motion stability during operation. The findings of this research offer valuable design guidance for the selection of appropriate plugging positions and fits in precision cross roller bearings.

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Zhang, Shengdong. "Effect of Groove Structure on Lubrication Performance of Water-Lubricated Stern Tube Bearings". Lubricants 11, n.º 9 (5 de setembro de 2023): 374. http://dx.doi.org/10.3390/lubricants11090374.

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This study investigated the lubrication characteristics (i.e., the groove ratio and width) of water-lubricated stern tube bearings, based on the flexibility matrix method and lubrication theory. Considering the elastic deformation of the lining, a fluid structure interaction (FSI) model of the surface micro-groove texture of a water-lubricated stern tube bearing was established, and the correctness and rationality of the model were verified by experiments. Micro-grooved, surface-lubricated, water-lubricated stern tube bearings with three different cross-sectional shapes (rectangular, circular, and triangular) were designed. The influences of the groove area ratio and width on the bearing load-carrying capacity and friction coefficient were analyzed. At a groove area ratio of 0.31, the load-carrying capacity of the rectangular grooved stern tube bearing reached the maximum value and the friction coefficient reached the minimum value. It is recommended to design and use water-lubricated stern tube bearings, especially Thordon water-lubricated stern tube bearings, with rectangular micro-grooves, with a groove area ratio of 0.30–0.32, so that the best lubrication performance can be obtained. With the increase in the micro-groove width, the lubrication of water-lubricated stern tube bearings with partial rectangular micro-grooves is significantly better than that of others. Under the same conditions, the bearing load-carrying capacity and friction performance of local groove stern bearings is significantly better than that of global groove stern bearings.

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32

Tu, Wenbing, Jinwen Yang, Wennian Yu e Ya Luo. "Contact characteristic and vibration mechanism of rolling element bearing in the process of fault evolution". Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 235, n.º 1 (5 de janeiro de 2021): 19–36. http://dx.doi.org/10.1177/1464419320985707.

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The vibration response of rolling element bearing has a close relation with its fault. An accurate evaluation of the bearing vibration response is essential to the bearing fault diagnosis. At present, most bearing dynamics models are built based on rigid assumptions, which may not faithfully reveal the dynamic characteristics of bearing in the presence of fault. Moreover, previous similar works mainly focus on the fault with a specified size without considering the varying contact characteristics as the fault evolves. This paper developed an explicit dynamics finite element model for the bearing with three types of raceway faults considering the flexibility of each bearing component in order to accurately study the contact characteristic and vibration mechanism of defective bearings in the process of fault evolution. The developed model is validated by comparing its simulation results with both analytical and experimental results. The dynamic contact patterns between the rolling elements and the fault, the additional displacement due to the fault and the faulty characteristics within the bearing vibration signal during the fault evolution process are investigated. The analysis results from this work can provide practitioners an in-depth understanding towards the internal contact characteristics with the existence of raceway fault and theoretical basis for rolling bearing fault diagnosis.

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Javorova, Juliana, e Vassil Alexandrov. "Effects of fluid inertia and bearing flexibility on the performance of finite length journal bearing". IOP Conference Series: Materials Science and Engineering 174 (fevereiro de 2017): 012039. http://dx.doi.org/10.1088/1757-899x/174/1/012039.

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Kerst, Stijn, Barys Shyrokau e Edward Holweg. "A semi-analytical bearing model considering outer race flexibility for model based bearing load monitoring". Mechanical Systems and Signal Processing 104 (maio de 2018): 384–97. http://dx.doi.org/10.1016/j.ymssp.2017.11.008.

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35

Zhang, Jun Yan. "The Elastohydrodynamic Lubrication Analysis of Journal Bearing". Advanced Materials Research 988 (julho de 2014): 328–31. http://dx.doi.org/10.4028/www.scientific.net/amr.988.328.

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Based on the flexibility matrix method, the elastohydrodynamic lubrication performance of journal bearing are studied. Comparisons are made the effect of elastic deformation on the center orbit of connecting rod big end bearing. The results show that bearing eccentricity has far exceeded 1 near the maximum combustion pressure, considering the elastic deformation of connecting rod big end bearing, changing trend of bearing center orbit is the same at other times.

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36

Turnbull, R., R. Rahmani e H. Rahnejat. "The effect of outer ring elastodynamics on vibration and power loss of radial ball bearings". Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 234, n.º 4 (24 de agosto de 2020): 707–22. http://dx.doi.org/10.1177/1464419320951398.

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Ball bearings are an integral part of many machines and mechanisms and often determine their performance limits. Vibration, friction and power loss are some of the key measures of bearing performance. Therefore, there have been many predictive analyses of bearing performance with emphasis on various aspects. The current study presents a mathematical model, incorporating bearing dynamics, mechanics of rolling element-to-races contacts as well as the elastodynamics of the bearing outer ring as a focus of the study. It is shown that the bearing power loss in cage cycles increases by as much as 4% when the flexibility of the outer ring is taken into account as a thick elastic ring, based on Timoshenko beam theory as opposed to the usual assumption of a rigid ring in other studies. Geometric optimisation has shown that the lifetime power consumption can be reduced by 1.25%, which is a significant source of energy saving when considering the abundance of machines using rolling element bearings. The elastodynamics of bearing rings significantly affects the radial bearing clearance through increased roller loads and generated contact pressures. The flexible ring dynamics is shown to generate surface waviness through global elastic wave propagation, not hitherto taken into account in contact dynamics of rollers-to-raceways which are generally considered to be subjected to only localised Hertzian deflection. The elastodynamic behaviour reduces the elastohydrodynamic film thickness, affecting contact friction, wear, fatigue, vibration, noise and inefficiency.

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37

Heo, B., H. Bittner, M. L. Shumway e I. Y. Shen. "Identifying Damping of a Gyroscopic System Through the Half-Power Method and Its Applications to Rotating Disk/Spindle Systems". Journal of Vibration and Acoustics 121, n.º 1 (1 de janeiro de 1999): 70–77. http://dx.doi.org/10.1115/1.2893950.

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This paper applies the half-power method to identify damping of a gyroscopic system. At first, the underlying principle of the half-power method for damped, gyroscopic systems is explained. Then the method is demonstrated on a rotating disk/spindle system often used in computer hard disk drives. The disk/spindle system consists of multiple elastic disks mounted on a rigid spindle supported by ball bearings. The flexibility of the bearings allows the spindle to undergo rigid-body translation and rocking. Calibrated experiments were conducted in vacuum to obtain frequency response functions at different rotational speed. Application of the half-power method shows that the disk and bearing dampings are independent of rotational speed and can be modeled adequately as viscous damping. Moreover, the damping of the ball bearings is two orders of magnitude smaller than that of a fluid-film bearing of similar size.

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38

Zhen, Jun Wei, Ling Li Cui e Xue Chen. "Mechanics Modeling for Bearing Rigid-Flexible Coupling Multi-Body System Based on ADAMS". Applied Mechanics and Materials 364 (agosto de 2013): 124–28. http://dx.doi.org/10.4028/www.scientific.net/amm.364.124.

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Rigid-flexible coupling model is the most common mechanics model for multi-body system, and discovering the law of multi-body system modeling is an important part of the study on multi-body mechanics. This paper uses finite element analysis software PATRAN to make flexibility treatment on the parts of deep groove ball bearing, combines with the virtual prototype technology and establishes the multi-flexibility body rigid-flexible coupling model which can truly reflect the dynamic characteristics of the bearing, and discusses the process and the matters needing attention for generating modal neutral file, realizes the precise modeling for fault bearing, and provides a new method for using virtual prototype to create model.

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39

Nielsen, Bo B., e Ilmar F. Santos. "Transient and steady state behaviour of elasto–aerodynamic air foil bearings, considering bump foil compliance and top foil inertia and flexibility: A numerical investigation". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 231, n.º 10 (2 de fevereiro de 2017): 1235–53. http://dx.doi.org/10.1177/1350650117689985.

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This work gives a theoretical contribution to the problem of modelling air foil bearings considering large sagging effects in the calculation of the non-linear transient and steady state response of a rigid rotor. This paper consists of two parts: the development of a miltiphysics model of the air foil bearing, and a numerical parameter study of a rigid journal supported in an air foil bearing with a partially supported top foil. The mathematical model of the air foil bearing is centred around the finite element models of both the air film and the top foil structure. These finite element models utilise two types of eight-node isoparametric elements. The rotor is modelled as a rigid body without rotational inertia, i.e. as a journal. The bump foil is included via a bilinear version of the simple elastic foundation model. This paper introduces the bilinear simple elastic foundation model, which combined with the top foil structure model, enables a separation of the top foil and the bump foil. A phenomenon associated within areas of the top foil is where the aerodynamic pressure is sub-ambient. The parameter study investigates the performance of three air foil bearings with partially supported top foils and one air foil bearing with a fully supported top foil. The steady state responses of a journal supported by these air foil bearings are investigated for varied rotational speeds and journal unbalances as well as the top foil sagging in the unsupported area. The study reveals that sub-harmonic vibrations associated with a large journal unbalance can be eliminated by a proper design layout of the bump foil, i.e. placement of the unsupported area. The positive effect is attributed to ‘equivalent shallow pockets’ formed by the sagging top foil.

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40

Nayak, Narayan C., e Pradip K. Ray. "Flexibility and performance relationships: evidence from Indian bearing manufacturing firm". International Journal of Modelling in Operations Management 1, n.º 1 (2010): 67. http://dx.doi.org/10.1504/ijmom.2010.035255.

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41

Nicholas, J. C., e L. E. Barrett. "The Effect of Bearing Support Flexibility on Critical Speed Prediction". A S L E Transactions 29, n.º 3 (janeiro de 1986): 329–38. http://dx.doi.org/10.1080/05698198608981693.

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42

Yefimenko, Olena. "ENGINEERING METHOD FOR CALCULATING STEEL-REINFORCED CONCRETE ELEMENTS WITH FLEXIBILITY". ACADEMIC JOURNAL Series: Industrial Machine Building, Civil Engineering 2, n.º 53 (31 de outubro de 2019): 85–89. http://dx.doi.org/10.26906/znp.2019.53.1897.

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In the article presents an engineering method for calculating compressed flexible reinforced concrete elements with sheet reinforcement over a steel cross section. The results of the calculation are compared with the experimental data. Calculation ofload-bearing capacity of reinforced concrete flexible elements with sheet reinforcement is based on the method of boundarystates. The work of specimens under load and the nature of the load-bearing capacity depending on the height and eccentricity of the effort were investigated. The proposed method of calculating compressed elements with sheet reinforcement on asteel-cross-section allows to take into account their flexibility in both axial and out-of-center application of load.

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43

Gao, Zhen Xing, e Ling Xu. "The Experimental Research and Contrastive Analysis on the Attachments of Semi-Rigid Nodes in the Beam-Column T-Typed Member and End Plate of Steel Frame". Advanced Materials Research 243-249 (maio de 2011): 1163–67. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.1163.

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Based on the connection tests of the semi-rigid nodes in the beam-column T-typed member and end plate of steel frame, this paper analyzes the failure phenomena, stiffness, bearing capacity and flexibility of two types of attachments. And according to the tests results, it compares the two types of attachments each other and proposes that T-typed member is a better type of attachment on its bearing capacity and flexibility. Therefore, it provides the experimental basis for the ideal design and application of attachments among the semi-rigid nodes in steel structures.

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44

Yan, Jing Jing, Cheng Jun Wang, Qing Hai Cui, Xing Jin, Min Fan e Meng Fan. "Study on Rapid Evaluation of Bearing Capacity of Arch Bridge Structure". Applied Mechanics and Materials 405-408 (setembro de 2013): 1562–66. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.1562.

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This paper introduced a concept of frequency inspection coefficient to find relationship among frequency inspection coefficients of static flexibility, strain and structure dynamic load. Explored this theory resemblance of structure stiffness evaluation which based on frequency inspection coefficient and static flexibility inspection coefficient separately, and verified reliability of this method which aiming at arch bridge via the result of measured static and dynamic test data of sample bridge.

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45

Witanowski, Łukasz, Łukasz Breńkacz, Natalia Szewczuk-Krypa, Marta Dorosińska-Komor e Bartosz Puchalski. "Comparable analysis of PID controller settings in order to ensure reliable operation of active foil bearings". Eksploatacja i Niezawodnosc - Maintenance and Reliability 24, n.º 2 (22 de abril de 2022): 377–85. http://dx.doi.org/10.17531/ein.2022.2.19.

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In comparison to the traditional solutions, active bearings offer great operating flexibility, ensure better operating conditions over a wider range of rotational speeds and are safe to use. In order to ensure optimum bearing performance a bearing control system is used that adapts different geometries during device operation. The selection of optimal controller parameters requires the use of modern optimization methods that make it possible to quickly achieve the assumed parameters. This article presents the method that has been employed to select the parameters of a proportional integral derivative (PID) controller, in which both stochastic algorithms and hybrid methods have been compared. The results show that all of the used algorithms were able to reach the global optimum but only the hybrid algorithm was repeatable in all runs within a low value of the standard deviation. The best solution will be proposed in the future to control an active foil bearing. Analysing of this paper would help to prevent failures of active foil bearing used in the designed rotating machine.

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46

Krynke, Marek, Ludwik Kania e Eugeniusz Mazanek. "Modelling the Contact between the Rolling Elements and the Raceways of Bulky Slewing Bearings". Key Engineering Materials 490 (setembro de 2011): 166–78. http://dx.doi.org/10.4028/www.scientific.net/kem.490.166.

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In slewing bearings, a great number of contact pairs are present on the contact surfaces between the rolling elements and raceways of the bearing. Computations to determine the load of the individual rolling elements, taking into account the flexibility of the bearing ring, are most often carried out using the finite element method. Construction of a FEM full model of the bearing, taking into account the shape of the rolling elements and the determination of the contact problem for every rolling element, leads to a singularity of stiffness matrix, which in turn makes the problem impossible to solve. In FEM models the rolling elements are replaced by one-dimensional finite elements (linear elements) to simplify the computation procedure and to obtain an optimal time for computations. The methods of modelling the rolling elements in the slewing bearing, in which balls have been replaced by truss elements with a material non-linear characteristic located between the raceway centres of the curvatures in their axial section, are presented in the paper.

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47

Hu, Jong Wan, e Yong-il Cho. "Pilot Study for Investigating the Cyclic Response of the Recentering Bridge Bearing System Combined with the Friction Damper". Advances in Materials Science and Engineering 2016 (2016): 1–17. http://dx.doi.org/10.1155/2016/3701292.

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The bridge bearing is one of the component members which provide resting supports between piers and decks. The bridge bearing is intended to control longitudinal movement caused by traffic flow and thermal expansion, thereby reducing stress concentration. In high seismicity area, the bridge bearing has been utilized as the base isolation system to mitigate acceleration transferred from the ground. Although the existing bridge bearing installed between superstructure and substructure provides extra flexibility to the base of the entire structure, considerable permanent deformation occurs due to lack of recentering capacity after earthquake. It is required to spend extra cost for repairing impaired parts. The bridge bearings integrated with superelastic shape memory alloy (SMA) devices used for upgrading the recentering effect into the friction damper are proposed in this study. The refined finite element (FE) analyses are introduced to reproduce the response of such new structures under cyclic loading condition. The bridge bearing systems that maintain uniform recentering capability are designed with various friction coefficients so as to examine energy dissipation and residual deformation through FE analyses. After observing FE analysis results, optimal design for the recentering bridge bearing system will be proposed to take advantage of energy dissipation and self-centering capacity.

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Machado, C., S. Baudon, M. Guessasma, V. Bourny, J. Fortin, R. Bouzerar e P. Maier. "An Original DEM Bearing Model with Electromechanical Coupling". International Journal of Computational Methods 16, n.º 05 (28 de maio de 2019): 1840006. http://dx.doi.org/10.1142/s0219876218400066.

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We have developped an original 2D modeling of bearings by Discrete Element Method (DEM). The mechanical behavior and the dynamic of a bearing is well reproduced. An electromechanical coupling is introduced to provide monitoring solutions. In practice, the mechanical state in real-time is usually unknown and existing numerical methods are restricted. Electromechanical coupling seems to be able to indirectly measure the dynamic loading of the bearing. This behavior leads to the development of a new monitoring method based on electrical signatures. The study proposes an original method of simulating the bearings to correlate dynamic mechanical state with electrical responses, over time. The bearing is seen as a polydisperse granular chain where rolling elements and cage components interact with a Hertzian contact model. Moreover, rings (and housing) are also taken into account using a cohesive model. Indeed, while many studies have been conducted on bearing simulation using FEM and multibody approaches, this discrete approach gives relevant informations on physical phenomena in the contact interface. One of our objectives is to investigate the sensitivity of the electrical measurement due to typical mounting. The ability of DEM to describe accurately the mechanical state of a bearing has been established by means of a comparison with FEM, of load distributions in a static case. In dynamic, the consequences associated with the flexibility of the bearing mounting (rigid and elastic rings) are studied with mechanical stresses acting in rings and with the load distribution. Also, by accessing dynamic stresses, this modeling opens certain possibilities on studies of damage and wear by providing the history of contact.

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Mark, W. D. "Effects of Bearing Offset and Flexibility on the Mesh Force Distribution of Spiral Bevel Gears". Journal of Mechanisms, Transmissions, and Automation in Design 110, n.º 2 (1 de junho de 1988): 203–10. http://dx.doi.org/10.1115/1.3258927.

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For straight or spiral bevel gears of nominal spherical involute design, the resultant total force vector transmitted by the gear mesh, in the absence of friction, lies in the plane of tooth contact. This force vector can be characterized by three scalar components, two orthogonal force components lying in the plane of contact and the resultant moment taken about the nominal center of the zone of contact. Equations for these three generalized force components are derived. The equations are expressed in terms of tooth pair/gear body stiffnesses, bearing/bearing support flexibility influence coefficients, the shaft input torque, deviations of the tooth running surfaces from perfect spherical involute surfaces, and bearing centerline offsets from the positions occupied by the base cone axes of the perfect involute bevel gear counterparts to the actual gears under consideration. Inertial forces arising from transverse and axial vibrations of the gear bodies are assumed to be negligible in comparison with the bearing support reaction forces.

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50

Xin, Jiajia, Zhi Wang, Xu Hao, Xiaoye Qi, Yongjie Wang e Baogang Wen. "Dynamic Characteristics Analysis of Cylindrical Roller Bearing with Dimensional Deviations in Cage Pocket". Applied Sciences 14, n.º 20 (16 de outubro de 2024): 9433. http://dx.doi.org/10.3390/app14209433.

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Dimensional deviations in the cage pocket of a roller bearing can significantly affect the bearing’s dynamic performance, directly determining the positional stability of the roller. These deviations can result in roller misalignment, increasing friction and wear. Deviations arise from machining errors and deformation during motion, etc. A dynamic model of a cylindrical roller bearing that accounts for cage flexibility was developed to explore the impact of deviations. The flexible cage provides a more realistic representation compared to the rigid cage. The effects of deviations in the length and width of the cage pocket on the bearing’s dynamic behavior were analyzed, and the results show that deviations in cage pocket dimensions lead to notable changes in bearing dynamics. Specifically, when the length deviation is negative and increasing, the amplitude of cage motion decreases, while both transitional and rotational speeds rise. It also causes greater fluctuations in the rotational speeds of the inner ring and rollers. Conversely, the cage’s equivalent stress and the contact load decrease and the amplitude of cage motion increases with increases in width deviation.

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