Статті в журналах: "High-speed bearings"

1

TSUMAKI, Nabuo, and Tomoaki INOUE. "High Speed Bearings." Journal of the Society of Mechanical Engineers 94, no. 867 (1991): 121–25. http://dx.doi.org/10.1299/jsmemag.94.867_121.

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2

BRECHER, CHRISTIAN, STEPHAN NEUS, MARCUS GAERTNER, LEONARDO CATANA, FELICIANO GRECO, GULLERMO MORALES-ESPEJEL, and DEFENG LANG. "NEW BEARING STEEL FOR HIGH-SPEED APPLICATIONS." MM Science Journal 2021, no. 6 (December 15, 2021): 5334–39. http://dx.doi.org/10.17973/mmsj.2021_12_2021129.

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The requirements for speed suitability and fatigue strength of motor spindle bearings are constantly increasing. These challenges can be met by further developing the spindle bearings, e.g. by using higher-performance bearing steels. In the following, the experimental investigation results of a spindle bearing made of a new raceway steel tested on a high-speed rolling bearing test rig are presented. Spindle bearings of the type 7008 (hybrid execution) were tested in an endurance run at a rotational speed of 46 krpm and 3 kN axial load. The operating behaviour was validated based on the bearing outer ring temperature and the vibration behaviour. Microscope analysis of the raceways after the test shows that the new steel has good resistance to micropitting and surface fatigue. The calculated contact pressures, wear parameter and lifetime for the bearings in the tests show that the performance limits of spindle bearings are significantly higher than initially assumed.

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3

Żywica, Grzegorz, Paweł Bagiński, and Artur Andrearczyk. "Analysis of Thermal Damage in the High-Speed Foil Bearing." Solid State Phenomena 260 (July 2017): 266–77. http://dx.doi.org/10.4028/www.scientific.net/ssp.260.266.

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The article discusses experimental research and simulation testing on prototypical foil bearings. All experimental tests were conducted on a special test rig which makes it possible to operate in various conditions and within a wide range of speeds. As a result of the study, it turned out that adverse operating conditions caused almost instant bearing damage, accompanied by a significant rise in temperature. The main factors affecting the durability of foil bearings were material covering mating surfaces, bearing geometry, way of assembling the bearing, rotational speed and load. To better understand the physical phenomena occurring in foil bearings, a numerical model has been developed which allowed carrying out thermal analyses. The analysis of heat flow in the bearing's structure showed that, because of the system geometry, significant problems with proper removal of large amounts of heat continued to be experienced, which may have led to an accelerated rate of fatigue damage and shorter bearing life. This phenomenon can occur in bearings operating under tough conditions (e.g. at low speeds or under heavy loads). The research showed that the development of a new foil bearing is a very difficult task and requires many aspects to be taken into account, including the aspects directly related to the operation of the bearing itself, as well as those related to the rotor's operation and characteristics of the machine.

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4

Franchek, N. M., and D. W. Childs. "Experimental Test Results for Four High-Speed, High-Pressure, Orifice-Compensated Hybrid Bearings." Journal of Tribology 116, no. 1 (January 1, 1994): 147–53. http://dx.doi.org/10.1115/1.2927031.

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In this study, four hybrid bearings having different geometric configurations were experimentally tested for their static and dynamic characteristics, including flowrate, load capacity, rotordynamic coefficients, and whirl frequency ratio. The four bearings included a square-recess, smooth-land, radial-orifice bearing (baseline), a circular-recess bearing, a triangular-recess bearing, and an angled-orifice bearing. Each bearing had the same orifice diameter rather than the same pressure ratio. Unique to these test results is the measurement of the added mass terms, which became significant in the present tests because of high operating Reynolds numbers. Comparisons of the results were made between bearings to determine which bearing had the best performance. Based on the parameters of interest, the angled-orifice bearing has the most favorable overall performance.

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5

Pettinato, B. C., and P. DeChoudhury. "Rotordynamic and Bearing Upgrade of a High-Speed Turbocharger." Journal of Engineering for Gas Turbines and Power 125, no. 1 (December 27, 2002): 95–101. http://dx.doi.org/10.1115/1.1519273.

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The paper discusses the redesign of a high-speed turbocharger for improved bearing life and mechanical operation. The bearings were changed from a pair of combination journal/thrust bearings to a pair of redesigned journal bearings with double acting thrust bearing at the center of the unit. Internal oil passages, drain cavities, and seals were also revised. These modifications resulted in reduced oil leakage across end seals, reduced coke buildup at the turbine, increased thrust load capacity, and improved rotordynamics. Both the analytical and experimental results, which consisted of bearing performance and vibration data of original and modified systems are presented.

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6

Xiu, Shi Chao, Shi Qiang Gao, and Zhi Li Sun. "Study on Thermal Properties of Hybrid Journal Bearing for Super High Speed Grinding Machine." Advanced Materials Research 126-128 (August 2010): 808–13. http://dx.doi.org/10.4028/www.scientific.net/amr.126-128.808.

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As the high speed bearings, hybrid journal bearings are usually used in high and super high speed grinding machine spindle system. Since the bearing operates under high speed conditions, the excessive temperature rise of bearing is a key factor to lower the accuracy of the spindle system and limit the bearings working speed, so restrict the bearing applications. In this paper, the model of hybrid journal bearing is established to analyze the heat mechanism. In addition, the temperature field distribution for the certain hybrid journal bearing at high speed is studied by ANSYS considering the heat transfer characters between fluid and solid. The experiment of temperature for hybrid journal bearing system in super high speed grinding machine is also performed. The thermal properties and the measure for controlling temperature rise of such bearings are analyzed.

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7

KAKUTA, KAZUO. "Ultra high speed rolling bearings." Journal of the Japan Society for Precision Engineering 53, no. 7 (1987): 1005–8. http://dx.doi.org/10.2493/jjspe.53.1005.

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8

Li, He, Yu Wang, Deen Bai, Fuyan Lyu, Kuidong Gao, and Qingliang Zeng. "Suspending force modeling based on nonlinear acoustics and high-speed running experiments for an ultrasonic journal bearing." Advances in Mechanical Engineering 12, no. 7 (July 2020): 168781402094047. http://dx.doi.org/10.1177/1687814020940470.

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As a kind of promising noncontact bearings, ultrasonic bearings actuated by smart materials such as lead zirconate titanate ceramics show a good application prospect in high-speed machines and precision-measuring devices. The suspending force is one of the most important parameters that play a dominated role on the bearing’s static and dynamic performance. A suspending force model based on acoustic radiation theory for cylindrical object near sound source is built to predict the radial carrying capacity of an ultrasonic bearing actuated by three piezoelectric transducers. To validate the model, an ultrasonic bearing prototype is developed and a testing system is established. For observing the bearing’s dynamic running performance at high speeds, the bearing’s running experiment is carried out and the rotor center’s trajectory data and frequency spectrum are acquired to analyze the bearing’s dynamic characteristics at high speeds. The suspending force model and running performance experiments will contribute to the design, detection, and test of this type of bearings.

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9

Cui, Li. "A new fatigue damage accumulation rating life model of ball bearings under vibration load." Industrial Lubrication and Tribology 72, no. 10 (June 1, 2020): 1205–15. http://dx.doi.org/10.1108/ilt-05-2019-0180.

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Purpose Bearings in electric machines often work in high speed, light load and vibration load conditions. The purpose of this paper is to find a new fatigue damage accumulation rating life model of ball bearings, which is expected for calculating fatigue life of ball bearings more accurately under vibration load, especially in high speed and light load conditions. Design/methodology/approach A new fatigue damage accumulation rating life model of ball bearings considering time-varying vibration load is proposed. Vibration equations of rotor-bearing system are constructed and solved by Runge–Kutta method. The modified rating life and modified reference rating life model under vibration load is also proposed. Contrast of the three fatigue life models and the influence of dynamic balance level, rotating speed, preload of ball bearings on bearing’s fatigue life are analyzed. Findings To calculate fatigue rating life of ball bearings more accurately under vibration load, especially in high speed and light load conditions, the fatigue damage accumulation rating life model should be considered. The optimum preload has an obvious influence on fatigue rating life. Originality/value This paper used analytical method and model that is helpful for design of steel ball bearing in high speed, light load and vibration load conditions. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2019-0180/

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10

Makino, T., S. Morohoshi, and S. Taniguchi. "Thermohydrodynamic Performance of High-Speed Journal Bearings." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 210, no. 3 (September 1996): 179–87. http://dx.doi.org/10.1243/pime_proc_1996_210_497_02.

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This paper describes the performance characteristics of two types of journal bearings, tilting-pad and offset halves, operating under high-speed conditions where the journal peripheral speed is in excess of 100 m/s. Experimental investigations into bearing eccentricity, temperatures and dynamic coefficients were carried out with a specially designed test rig. These results are compared with theoretical data which are obtained from thermohydrodynamic lubrication theory. The agreement is satisfactory. However, further improvements are necessary to predict more accurate thermal performance of the unloaded pads.

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11

Ngo, Thi-Thao, Van-The Than, Chi-Chang Wang, and Jin H. Huang. "Analyzing characteristics of high-speed spindle bearing under constant preload." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 232, no. 5 (August 1, 2017): 568–81. http://dx.doi.org/10.1177/1350650117723484.

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Bearings play an important role in a high-speed spindle. Its characteristics are often influenced by speed and thermal effects. This paper presents an approach that combines an inverse method with a high-speed ball bearing model to determine the characteristics of a high-speed spindle bearing under constant preload in actual working conditions. With temperature distribution in the entire spindle obtained by the experimental inverse heat transfer model from the authors’ previous results, the change in bearing parameters is then calculated and subsequently replaced in the bearing model to analyze the change in bearing characteristics. As a result, thermal effects on a bearing’s dynamic contact angles, contact forces, contact stress, stiffness, and lubricant film thickness are presented. Moreover, analysis results indicate that a bearing’s stiffness and lubricant film thickness nonlinearly vary with the increase in speed, and the thermal effect significantly affects the lubricant film thickness. The results presented herein may be applied to develop a dynamic model for a high-speed spindle using a constant preload and provide useful information to avoid failure in lubrication.

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12

Zhang, Congcong, Yongliang Wang, Rixiu Men, Hong He, and Wei Chen. "Dynamic behaviors of a high-speed turbocharger rotor on elliptical floating-ring bearings." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 233, no. 12 (May 12, 2019): 1785–99. http://dx.doi.org/10.1177/1350650119849743.

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Floating-ring bearings are commonly used in automotive turbocharger applications due to their low cost and their suitability under extreme rotation speeds. This type of bearings, however, can become a source of noise due to oil whirl-induced sub-synchronous vibrations. The scope of this paper is to examine whether the concept of a floating-ring bearing with an elliptical clearance might be a solution to suppress sub-synchronous vibrations. A very time-efficient approximate solution for the Reynolds equation to the geometry of elliptical bearings is presented. The nonlinear dynamic behaviors of a turbocharger rotor supported by two concepts of elliptical floating-ring bearings are systematically investigated using run-up simulations. For the first concept of elliptical floating-ring bearings i.e. the outer bearing of the floating-ring bearing changed in the form of elliptical pattern (see Figure 1(b) in the article), some studies have pointed out that its steady-state and dynamic performances are superior to plain cylindrical floating-ring bearings but, the nonlinear run-up simulation results shown that this type of elliptical floating-ring bearings is not conducive to reduce the self-excited vibration levels. However, for the second type of elliptical floating-ring bearings i.e. both the inner and outer films of the floating-ring bearing changed in the form of elliptical pattern (see Figure 1(c) in the article), it is shown that the sub-synchronous vibrations have been considerably suppressed. Hence, the second noncircular floating-ring bearing design is an attractive measure to suppress self-excited vibrations.[Figure: see text]

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13

Ehrich, F. F., and S. A. Jacobson. "Development of High-Speed Gas Bearings for High-Power Density Microdevices." Journal of Engineering for Gas Turbines and Power 125, no. 1 (December 27, 2002): 141–48. http://dx.doi.org/10.1115/1.1498273.

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A 4.2-mm diameter silicon rotor has been operated in a controlled and sustained manner at rotational speeds greater than 1.3 million rpm and power levels approaching 5 W. The rotor, supported by hydrostatic journal and thrust gas bearings, is driven by an air turbine. This turbomachinery/bearing test device was fabricated from single-crystal silicon wafers using micro-fabrication etching and bonding techniques. We believe this device is the first micro-machine to operate at a circumferential tip speed of over 300 meters per second, comparable to conventional macroscale turbomachinery, and necessary for achieving high levels of power density in micro-turbomachinery and micro-electrostatic/ electromagnetic devices. To achieve this level of peripheral speed, micro-fabricated rotors require stable, low-friction bearings for support. Due to the small scale of these devices as well as fabrication constraints that limit the bearing aspect ratio, the design regime is well outside that of more conventional devices. This paper focuses on bearing design and test, and rotordynamic issues for high-speed high-power micro-fabricated devices.

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14

Prabhu Raja, Venugopal, P. Pal Pandian, Devara Venkata Krishna, and R. Sathiya Moorthy. "Minimization of Transient Temperature Fluctuations in High Speed Spindle Bearing." Applied Mechanics and Materials 592-594 (July 2014): 1114–18. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.1114.

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The performance of a high speed spindle is mainly attributed to the thermal behavior of spindle bearings. Hence, it is very significant to simulate the thermal behavior of spindle bearings. Finite element analysis is carried out for a typical high speed spindle by considering bearing and motor heat generation under various loading conditions to investigate the transient temperature rise of the spindle assembly. The influence of different cooling arrangements on the thermal behaviour of spindle bearings is then investigated with the objective of minimization of transient temperature fluctuations.

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15

Xiu, Shi Chao, Shi Qiang Gao, and Zhi Li Sun. "Analysis of Thermal Properties of Super-High Speed Hybrid Journal Bearing Based on ANSYS." Advanced Materials Research 118-120 (June 2010): 753–57. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.753.

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Hybrid journal bearings are used in the high and super high speed cases mainly, such as the super-high speed spindle system. Since the bearing operates under high speed conditions, the excessive temperature rise of the bearing is a major reason to lower the accuracy of the main shaft system and limit the bearings working speed higher, as a result, restrict the bearing applications. In this paper, the thermal properties and the heat mechanism of such bearings are analyzed. The mathematical model of hybrid journal bearing is established to analyze the mechanism of generating heat. In addition, the temperature field distribution for the certain hybrid journal bearing at speed of 10000 rpm is studied by means of software ANSYS considering the heat transfer characters between fluid and solid. An improved measure about temperature rise of hybrid journal bearing is presented.

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16

Lai, Tianwei, Yu Guo, Wei Wang, Yu Wang, and Yu Hou. "Development and Application of Integrated Aerodynamic Protuberant Foil Journal and Thrust Bearing in Turboexpander." International Journal of Rotating Machinery 2017 (2017): 1–12. http://dx.doi.org/10.1155/2017/8430943.

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Foil bearing provides compliant support and moderate Coulomb friction for rotor-bearing system, which is conducive to stability and reliability of high speed rotating machinery. In this paper, both hydrodynamic lubricated foil journal and foil thrust bearings are applied in a 150 m3·h−1 turboexpander for air separation. In the bearings, protuberant foil is chosen as the supporting subfoil due to its merits of easy fabrication and assembly. Static loading and deflection of the bearings are tested, respectively, before integration into the turboexpander. Afterwards, the loading and deflection curves of the journal and thrust bearings are polynomial fitted using least-square method. Then, performance tests are carried out on the rotor-bearing system, including transient speed-up, high speed, and speed-down processes. In the tests, the turboexpander supported by the hydrodynamic foil bearings operates smoothly with repeatability. Maximal rotor speed of the turboexpander reaches 52000 rpm with hydrodynamic lubricated protuberant foil bearings.

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17

Chan, D. S. H. "Nonlinear Analysis of Rotordynamic Instabilities in High-Speed Turbomachinery." Journal of Engineering for Gas Turbines and Power 118, no. 1 (January 1, 1996): 122–29. http://dx.doi.org/10.1115/1.2816527.

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A nonlinear approach based on the method of averaging has been developed to study unstable lateral vibrations of rotors in high-speed turbomachinery. The method makes use of an extended concept of bearing dynamic coefficients, which are defined by applying small perturbations to the dynamic equilibrium positions. The approach has been applied to determine the stability threshold of flexible rotors supported on short and tilting-pad journal bearings, respectively. Stability performance of systems supported on short journal bearings is improved by the presence of mass unbalance. However, for flexible rotors supported on tilting-pad journal bearings, increased unbalance can lead to lower rotordynamic stability margins. This has the significant implication that stability estimates from linear analysis are not always conservative. The present method provides a computationally more efficient way to understand the nonlinear vibration behavior of high-speed turbomachinery.

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18

Zhou, Quan, Yu Hou, and Ru Gang Chen. "Development of Foil Thrust Bearings with Simple Structure for Micro Turbines." Advanced Materials Research 368-373 (October 2011): 1392–95. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.1392.

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Because of the low power loss and high stability, foil bearings are suitable lubrication components for high speed rotational systems. At present, the foil bearings used in actual applications almost have complicated structure and are hard to manufacture. In this paper, two kinds of foil thrust bearings with simple structure are presented. Configurations of these two foil thrust bearings are introduced; meanwhile, the load capacity and running stability are also tested in a high speed micro turbine. It is shown that viscoelastic supported foil thrust bearing has higher load capacity and hemisphere convex dots supported foil thrust bearing is more stable in high speed operational condition.

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19

Liu, L. X., and Z. S. Spakovszky. "Effects of Bearing Stiffness Anisotropy on Hydrostatic Micro Gas Journal Bearing Dynamic Behavior." Journal of Engineering for Gas Turbines and Power 129, no. 1 (March 1, 2004): 177–84. http://dx.doi.org/10.1115/1.2180813.

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The high-speed microhydrostatic gas journal bearings used in the high-power density MIT microengines are of very low aspect ratio with an L∕D of less than 0.1 and are running at surface speeds of order 500m∕s. These ultra-short high-speed bearings exhibit whirl instability limits and a dynamic behavior much different from conventional hydrostatic gas bearings. The design space for stable high-speed operation is confined to a narrow region and involves singular behavior (Spakovszky and Liu, 2005, “Scaling Laws for Ultra-Short Hydrostatic Gas Journal Bearings,” ASME J. Vibr. Acoust., 127(3), pp. 254–261). This together with the limits on achievable fabrication tolerance, which can be achieved in the silicon chip manufacturing technology, severely affects bearing operability and limits the maximum achievable speeds of the microturbomachinery. This paper introduces a novel variation of the axial-flow hydrostatic micro gas journal bearing concept, which yields anisotropy in bearing stiffness. By departing from axial symmetry and introducing biaxial symmetry in hydrostatic stiffness, the bearing's top speed is increased and fabrication tolerance requirements are substantially relieved making more feasible extended stable high-speed bearing operation. The objectives of this work are: (i) to characterize the underlying physical mechanisms and the dynamic behavior of this novel bearing concept and (ii) to report on the design, implementation, and test of this new microbearing technology. The technical approach involves the combination of numerical simulations, experiment, and simple, first-principles-based modeling of the gas bearing flow field and the rotordynamics. A simple description of the whirl instability threshold with stiffness anisotropy is derived explaining the instability mechanisms and linking the governing parameters to the whirl ratio and stability limit. An existing analytical hydrostatic gas bearing model is extended and modified to guide the bearing design with stiffness anisotropy. Numerical simulations of the full nonlinear governing equations are conducted to validate the theory and the novel bearing concept. Experimental results obtained from a microbearing test device are presented and show good agreement between the theory and the measurements. The theoretical increase in achievable bearing top speed and the relief in fabrication tolerance requirements due to stiffness anisotropy are quantified and important design implications and guidelines for micro gas journal bearings are discussed.

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20

Tlusty, J., I. Hernandez, S. Smith, and C. Zamudio. "High Speed High Power Spindles with Roller Bearings." CIRP Annals 36, no. 1 (1987): 267–72. http://dx.doi.org/10.1016/s0007-8506(07)62601-8.

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21

Huang, Zhao Dong, Bo Qian Fan, Xiao Ping Ouyang, Ling Ling Xu, and Zhi Gang Wang. "Development of Test Rig for High-Speed Railway Rolling Bearings." Applied Mechanics and Materials 101-102 (September 2011): 702–7. http://dx.doi.org/10.4028/www.scientific.net/amm.101-102.702.

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The rolling bearing test rig for heavy vehicles often works under heavy load and high speed, thus it requires high performance for the main shaft and mechanical structure. In this paper a design of test rig for high-speed railway rolling bearings is presented, in which a new structure is adopted to reduce the load on the support bearings. The basic idea is to position the load in a way that they can be balanced by each other.

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22

Wang, L. Q., G. C. Chen, L. Gu, and D. Z. Zheng. "Operating temperature in high-speed ball bearing." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 221, no. 3 (March 1, 2007): 353–59. http://dx.doi.org/10.1243/0954406jmes476.

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Frictional heating in high-speed bearings has been one of the primary factors for the failure of the main shaft bearing in aero engines. In order to exactly evaluate the heat generation and temperature in the bearing, a process has been developed, based on power consumption, which allows evaluation of heat generation in the high-speed ball bearing. A model for computing the temperature of the high-speed ball bearing with axisymmetric load is set up. In this model, heat sources in the raceways are treated as moving and the heat generation in the ball and cage is averaged on the circumferential zone through which the heat source passes. Using the process and model presented here, heat generation and the transient temperature of a ball bearing are obtained.

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23

Mizumoto, Hiroshi, Yoichi Tazoe, Tomohiro Hirose, and Katsuhiko Atoji. "Performance of High-Speed Precision Air-Bearing Spindle with Active Aerodynamic Bearing." International Journal of Automation Technology 9, no. 3 (May 5, 2015): 297–302. http://dx.doi.org/10.20965/ijat.2015.p0297.

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A high-speed precision air-bearing tool spindle with active aerodynamic bearing is proposed for improving the quality of machining using small-diameter cutting and grinding tools. The spindle is basically supported by aerostatic radial and thrust bearings. According to the spindle vibration detected by capacitance sensors, the wedge angle of the active aerodynamic bearing was controlled using piezoelectric actuators, thereby suppressing the spindle vibration. In the present paper, the performances of a prototype air-bearing spindle with single-row active aerodynamic bearing and an improved air-bearing spindle with double-row bearings are reported. Through experiments, it was demonstrated that the maximum rotational speed controlled by the active aerodynamic bearing is 800 Hz (48,000 min-1), and that the amplitude of spindle vibration can be suppressed to <50 nm at the rotational speed of 500 Hz (30,000 min-1).

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24

Heshmat, H. "Advancements in the Performance of Aerodynamic Foil Journal Bearings: High Speed and Load Capability." Journal of Tribology 116, no. 2 (April 1, 1994): 287–94. http://dx.doi.org/10.1115/1.2927211.

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An advanced-design, aerodynamic, air-lubricated foil journal bearing achieved a landmark speed of 2200 cps (132,000 rpm) and a major breakthrough in load performance of 673.5 kPa (97.7 psi). At 20°C (68°F) room temperature, normal ambient pressure, 995 cps (59,700 rpm) rotor speed, and with bearing projected pad area of 1081 mm2 (1.675 in2), the bearing demonstrated a load capacity of 727.8 N (163.6 lb). The bearing also exhibited low heat generation, with about 40°C (104°F) average side leakage temperature rise. For this demonstration, a highspeed spindle utilizing a pair of 35-mm (1.375-in.) bearings and supporting a test rotor with a mass of 1.545 kg (weighing 3.41 lb) and overall length of 211 mm (8.3 in.) was successfully taken to the limiting speed of the test apparatus. This speed was set by the maximum sound velocity (Mach 1) in the spindle’s turbine wheel. The rotor/bearing speed of 4.62 × 106 DN is beyond the capability of any advanced oil-lubricated ball bearings or conventional gas-lubricated bearings. The net result is a highly stable bearing at high operating speed. This paper presents the development of this air-lubricated foil journal bearing, the operational procedures used during testing, test results (dynamic analyses), and load performance characteristics.

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25

Waumans, T., J. Peirs, J. Reynaerts, and F. Al-Bender. "On the dynamic stability of high-speed gas bearings: stability study and experimental validation." International Journal Sustainable Construction & Design 2, no. 2 (November 6, 2011): 342–51. http://dx.doi.org/10.21825/scad.v2i2.20531.

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Анотація:

For high-speed applications, gas lubricated bearings offer very specific advantages over other,more conventional bearing technologies: a clean and oil-free solution, virtually wear-free operation, lowfrictional losses, wide operating temperature range, etc. However, the principal drawback involved in theapplication of high-speed gas bearings concerns the dynamic stability problem. Successful applicationtherefore requires control of the rotor-bearing dynamics so as to avoid instabilities.After a detailed study of the dynamic stability problem and the formulation of a convenient stability criterium,a brief overview is given of the currently existing bearing types and configurations for improving the stability.In addition, three strategies are introduced: (i) optimal design of plain aerostatic bearings; (ii) modification ofthe bearing geometry to counteract the destabilising effects in the gas film; and (iii) introduction of dampingexternal to the gas film as to compensate for the destabilising effects.These strategies are worked out into detail leading to the formulation of a series of design rules. Theireffectiveness is validated experimentally at a miniature scale. In recent experiments a rotational speed of1.2 million rpm has been achieved with a 6 mm rotor on aerodynamic journal bearings, leading to a recordDN-number of 7.2 million.

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26

Miyanaga, Norifumi, and Jun Tomioka. "Stability Analysis of Herringbone-Grooved Aerodynamic Journal Bearings for Ultra High-Speed Rotations." International Journal of Materials, Mechanics and Manufacturing 4, no. 3 (2015): 156–61. http://dx.doi.org/10.7763/ijmmm.2016.v4.246.

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27

Zheng, De-xing, Weifang Chen, and Miaomiao Li. "An improved model on forecasting temperature rise of high-speed angular contact ball bearings considering structural constraints." Industrial Lubrication and Tribology 70, no. 1 (January 8, 2018): 15–22. http://dx.doi.org/10.1108/ilt-06-2016-0133.

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Анотація:

Purpose Thermal performances are key factors impacting the operation of angular contact ball bearings. Heat generation and transfer about angular contact ball bearings, however, have not been addressed thoroughly. So far, most researchers only considered the convection effect between bearing housings and air, whereas the cooling/lubrication operation parameters and configuration effect were not taken into account when analyzing the thermal behaviors of bearings. This paper aims to analyze the structural constraints of high-speed spindle, structural features of bearing, heat conduction and convection to study the heat generation and transfer of high-speed angular contact ball bearings. Design/methodology/approach Based on the generalized Ohm’s law, the thermal grid model of angular contact ball bearing of high-speed spindle was first established. Next Gauss–Seidel method was used to solve the equations group by Matlab, and the nodes temperature was calculated. Finally, the bearing temperature rise was tested, and the comparative analysis was made with the simulation results. Findings The results indicate that the simulation results of bearing temperature rise for the proposed model are in better agreement with the test values. So, the thermal grid model established is verified. Originality/value This paper shows an improved model on forecasting temperature rise of high-speed angular contact ball bearings. In modeling, the cooling/lubrication operation parameters and structural constraints are integrated. As a result, the bearing temperature variation can be forecasted more accurately, which may be beneficial to improve bearing operating accuracy and bearing service life.

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28

Hou, Yu, Qi Zhao, Yu Guo, Xionghao Ren, Tianwei Lai, and Shuangtao Chen. "Application of Gas Foil Bearings in China." Applied Sciences 11, no. 13 (July 5, 2021): 6210. http://dx.doi.org/10.3390/app11136210.

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Gas foil bearing has been widely used in high-speed turbo machinery due to its oil-free, wide temperature range, low cost, high adaptability, high stability and environmental friendliness. In this paper, state-of-the-art investigations of gas foil bearings are reviewed, mainly on the development of the high-speed turbo machinery in China. After decades of development, progress has been achieved in the field of gas foil bearing in China. Small-scale applications of gas foil bearing have been realized in a variety of high-speed turbo machinery. The prospects and markets of high-speed turbo machinery are very broad. Various high-speed turbomachines with gas foil bearings have been developed. Due to the different application occasions, higher reliability requirements are imposed on the foil bearing technology. Therefore, its design principle, theory, and manufacturing technology should be adaptive to new application occasions before mass production. Thus, there are still a number of inherent challenges that must be addressed, for example, thermal management, rotor-dynamic stability and wear-resistant coatings.

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29

Simkulet, Vladimir, Marek Kočiško, Zuzana Hutyrová, and Veronika Fečová. "Analysis of the Damage Causes of High Speed Bearing Failure." Applied Mechanics and Materials 616 (August 2014): 200–206. http://dx.doi.org/10.4028/www.scientific.net/amm.616.200.

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High speed bearings are specified with mechanical properties, technological parameters and defined microstructure too. When these qualities are not respected in the manufacture, arise significant damage and consequently their not running ability. Cause of damage can also be bad operating conditions during its operation running. In this work microstructure characteristics are evaluated due to significant damage of the high speed bearings and thus its rejection of traffic. After microstructure investigation was not changed this microstructure but in some places micro hardness value was below the limit value, which is given by the producer and it was a consequence of bearing damage.

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30

Chen, C. H., K. W. Wang, and Y. C. Shin. "An Integrated Approach Toward the Dynamic Analysis of High-Speed Spindles: Part I—System Model." Journal of Vibration and Acoustics 116, no. 4 (October 1, 1994): 506–13. http://dx.doi.org/10.1115/1.2930456.

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Experimental evidence (Shin, 1992) has shown that the natural frequencies of high-speed spindles with angular contact ball bearings decrease with increasing rotational speed. A recent study (Wang et al., 1991) illustrated that this phenomenon is caused by stiffness change of the bearings. A simplified approximation was used in the past analysis to examine the bearing radial stiffness at high speeds. While the investigation explained the experimental observations in a qualitative sense, the analytical results so far are not sufficient to quantitatively describe the spindle behavior under high speed and load operations due to the assumptions and approximations made in the modeling process. This paper presents an integrated approach toward the modeling of flexible spindles with angular contact ball bearings from basic principles. The local dynamics of the bearings are coupled with the global shaft motion. The model derived includes both the longitudinal and transverse vibrations of the shaft interacting with the nonlinear bearings. The influences of shaft speed on the bearing stiffness matrix and the system frequencies are studied. It is shown that the spindle dynamic behavior can vary substantially as speed increases due to the bearing gyroscopic moment and centrifugal force. These effects have been ignored in most of the previous spindle models. This unique characteristic, which is critical to high-speed machinery, is rigorously studied for the first time. Lab tests are conducted to validate the model. The analytical predictions are quantitatively verified by the experimental results.

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31

Klebanov, Ya M., V. V. Murashkin, K. A. Polyakov, and A. I. Danil’chenko. "Dynamic Loading in High-Speed Ball Bearings." Russian Engineering Research 38, no. 2 (February 2018): 65–71. http://dx.doi.org/10.3103/s1068798x18020107.

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32

Brecher, Christian, Alexander Hassis, and Jens Rossaint. "Cage Friction in High-Speed Spindle Bearings." Tribology Transactions 57, no. 1 (November 21, 2013): 77–85. http://dx.doi.org/10.1080/10402004.2013.843738.

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33

MATSUO, Eito, and Masatomo MATSUO. "Development of high speed water lubrication bearings." Proceedings of the Machine Design and Tribology Division meeting in JSME 2018.18 (2018): 2C3–4. http://dx.doi.org/10.1299/jsmemdt.2018.18.2c3-4.

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34

Boyarko, N. N., V. A. Demchenko, A. G. Parkhomenko, and I. S. Skuba. "Bench tests on high-speed sliding bearings." Chemical and Petroleum Engineering 22, no. 5 (May 1986): 208–11. http://dx.doi.org/10.1007/bf01150312.

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35

Ye, Zhen Huan, and Li Qin Wang. "Cage Instabilities in High-Speed Ball Bearings." Applied Mechanics and Materials 278-280 (January 2013): 3–6. http://dx.doi.org/10.4028/www.scientific.net/amm.278-280.3.

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The dynamic model of the cage in high-speed ball bearing was developed according to the geometry and force relationship between bearing elements. Based on this dynamic model, cage instability was researched through mass center whirl. The effect of clearance ratio, load and bearing rotation speed on cage instability were studied by taking type 7004 angular ball bearing as an example. The results shown that the increase of clearance ratio and radial load makes cage stability lowered, and the cage stability could be enhanced by increasing the axial load and bearing rotation speed.

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36

Olaru, D. N., and M. D. Gafitanu. "Lubrication safety in high-speed ball-bearings." Lubrication Science 9, no. 4 (August 1997): 365–89. http://dx.doi.org/10.1002/ls.3010090404.

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37

Spakovszky, Z. S., and L. X. Liu. "Scaling Laws for Ultra-Short Hydrostatic Gas Journal Bearings." Journal of Vibration and Acoustics 127, no. 3 (June 1, 2005): 254–61. http://dx.doi.org/10.1115/1.1897739.

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The journal bearings of the MIT micro-devices are located at the outer periphery of the rotor and are designed to operate at rotational speeds of order two million rpm in order to enable high-power densities with turbomachinery tip speeds near 500m/s. These journal bearings are very short compared to their relatively large bearing diameters such that the bearing L/D is typically less than 0.1, that is at least one order of magnitude smaller than in conventional gas bearings. Thus, the ultra-short micro gas journal bearings essentially act as short annular seals and operate at Reynolds numbers of order 300, two orders of magnitude lower than conventional annular seals. The concepts that hold for turbulent flow, large scale annular seals do not apply to micro bearings and the laminar flow regime sets new challenges in the design, implementation and operation of ultra-short, high-speed gas bearings. In order to reach the goal of operating the MIT micro devices at full design speed, the micro-bearing design must be improved and engineering solutions need to be found to overcome the challenges of high-speed bearing operation. This paper is the first to derive the scaling laws for the dynamics of ultra-short hydrostatic gas journal bearings. The theory is established from first principles and enables a physics based characterization of the dynamic behavior of ultra-short hydrostatic gas bearings. The derived scaling laws for natural frequency and damping ratio show good agreement with experimental data. A simple criterion for whirl instability is found that only depends on bearing geometry. The scaling laws together with this criterion are used to delineate engineering solutions critical for stable high-speed bearing operation. Design charts are developed which provide the link between fabrication tolerances, bearing performance, and the tolerable level of rotor unbalance for a minimum required whirl ratio.

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38

Wang, Lin, and Hua Xu. "Experimental Study on the Dynamic Performance of a New High-Speed Spindle Supported by Water-Lubricated Hybrid Bearings." Shock and Vibration 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8297834.

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The dynamic performance of a new high-speed spindle supported by water-lubricated hybrid bearings is experimentally studied on a test rig. The present design allows the speed of the spindle up to 30,000 rpm, with a bearing internal diameter of 40 mm, which makes it possible to simulate many actual machining processes. Some experiments have been presented to study the mechanical and thermal behaviors of the spindle and its supporting hybrid bearings. The maximum temperature rise is less than 15°C with a speed of 30,000 rpm and a water supply pressure of 2.5 MPa. The spindle radial run-out of the rotational frequency is about 1 µm. Stability of the spindle system has been improved. The experimental results indicate that water-lubricated hybrid bearings are valuable choices to replace ceramic bearings and air bearings as support for spindles under high-speed, high-precision, and heavy-load machining conditions.

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39

Faria, Marco Tulio C., and Luis San Andre´s. "On the Numerical Modeling of High-Speed Hydrodynamic Gas Bearings." Journal of Tribology 122, no. 1 (March 8, 1999): 124–30. http://dx.doi.org/10.1115/1.555335.

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A numerical study of high-speed hydrodynamic gas bearing performance is presented using both finite element and finite difference methods. Efficient numerical procedures are developed to analyze diffusive-convective thin film gas flows in some simple geometries. A novel direct finite element formulation employing a new class of shape functions is specially devised to solve the Reynolds equation for compressible fluids. The formulation is as computationally efficient as the classical upwind finite element schemes without introducing artificial diffusion into the solution. Bearing load-capacity, static stiffness coefficients and frequency-dependent force coefficients are calculated for gas-lubricated plane and Rayleigh step slider bearings. [S0742-4787(00)01701-X]

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40

Borchert, Uwe, Antonio Delgado, and Janusz A. Szymczyk. "Development and Testing of Air Foil Bearing System for an Automotive Exhaust Gas Turbocharger." Applied Mechanics and Materials 831 (April 2016): 71–80. http://dx.doi.org/10.4028/www.scientific.net/amm.831.71.

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Lubricated bearings are usually used to support and guide the shafts in gas turbines, exhaust gas turbochargers and other turbomachines. The lubricant is also used for cooling the hot parts such as the turbine side of the rotor. The high temperature condition effects a contamination of the compressed air by evaporating the lubricant. In special applications an oil-free operation has to be guaranteed. In other applications an oil lubricated bearing system prevents an immediate engine stop. The use of air foil bearings eliminates the disadvantages of the oil lubricated bearings. An air foil bearing works self-adjusting the necessary gap which depends on relative speed of the rotor and the stator surfaces and on the viscosity of the lubricating fluid. A low rotor speed requires a small bearing gap, whereas the gap must be enlarged for high speed at constant viscosity of the lubricant. An air foil bearing works contact-free in a wide speed range even at small rotation speed depending on design. On an experimental basis an air foil bearing system was developed and tested for a standard automotive exhaust gas turbocharger. The developed bearings need no infrastructure for supplying with lubricant and its cooling and filtering. The air foil bearings was calculated and designed based on the estimated bearing loads. For the manufacturing of the radial wave springs a procedure was developed. A test facility was set up for the experiments. The modified rotor works at the standard rotation speed of 80000 rpm. The bearings support and guide the shaft contact-free (without wear) in a range of a few thousands of revolutions per minute up to the standard rotation speed.

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41

Spakovszky, Z. S., J. D. Paduano, R. Larsonneur, A. Traxler, and M. M. Bright. "Tip Clearance Actuation With Magnetic Bearings for High-Speed Compressor Stall Control." Journal of Turbomachinery 123, no. 3 (February 1, 2000): 464–72. http://dx.doi.org/10.1115/1.1370163.

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Magnetic bearings are widely used as active suspension devices in rotating machinery, mainly for active vibration control purposes. The concept of active tip-clearance control suggests a new application of magnetic bearings as servo-actuators to stabilize rotating stall in axial compressors. This paper presents a first-of-a-kind feasibility study of an active stall control experiment with a magnetic bearing servo-actuator in the NASA Glenn high-speed single-stage compressor test facility. Together with CFD and experimental data a two-dimensional, incompressible compressor stability model was used in a stochastic estimation and control analysis to determine the required magnetic bearing performance for compressor stall control. The resulting requirements introduced new challenges to the magnetic bearing actuator design. A magnetic bearing servo-actuator was designed that fulfilled the performance specifications. Control laws were then developed to stabilize the compressor shaft. In a second control loop, a constant gain controller was implemented to stabilize rotating stall. A detailed closed loop simulation at 100 percent corrected design speed resulted in a 2.3 percent reduction of stalling mass flow, which is comparable to results obtained in the same compressor by Weigl et al. (1998. ASME J. Turbomach. 120, 625–636) using unsteady air injection. The design and simulation results presented here establish the viability of magnetic bearings for stall control in aero-engine high-speed compressors. Furthermore, the paper outlines a general design procedure to develop magnetic bearing servo-actuators for high-speed turbomachinery.

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42

Sun, Kai, Lan Wang, and Xin Jun Zhao. "The Dynamic Optimization Analysis of High-Speed Hybrid Thrust Bearing." Advanced Materials Research 118-120 (June 2010): 507–11. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.507.

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In this paper, the dynamic characteristics of high-speed hybrid thrust bearing with four-recesses are optimized for different orifice diameter and supply pressure at a given speed condition, the dynamic moment coefficients of hybrid thrust bearing are analyzed, considering the thrust collar angular misalignment case to determine the optimization of orifice diameter and supply pressure under a given speed. The results provide certain reference to the hybrid thrust bearings used in high speed precision spindle.

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43

Youcef-Toumi, K., and S. Reddy. "Dynamic Analysis and Control of High Speed and High Precision Active Magnetic Bearings." Journal of Dynamic Systems, Measurement, and Control 114, no. 4 (December 1, 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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44

NIKOLAKOPOULOS, P. G., and C. A. PAPADOPOULOS. "HIGH SPEED JOURNAL BEARINGS LUBRICATED WITH ELECTRO-RHEOLOGICAL FLUIDS: AN EXPERIMENTAL INVESTIGATION." International Journal of Modern Physics B 10, no. 23n24 (October 30, 1996): 3045–55. http://dx.doi.org/10.1142/s0217979296001495.

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It is well known that the imposition of an electric field on an Electro-Rheological (ER) fluid alters the viscosity and as a consequence the f flow properties of the f fluid. If such a fluid is used to lubricate a journal bearing system, it is expected that the imposition of an electric field between the rotor and the stator will cause the alteration of the dynamic properties of the journal bearing. For the present, it has been proved that this is valid only for low speeds and high radial clearances of Couette type viscometers. In this paper an experiment in a high speeds (16000 to 65000 s −1) journal bearing with small radial clearance is presented. The experiment performed has showed the phenomenon and has proved that the ER FLUID at high shear rates under constant temperature, follows the Bingham model in realistic bearings. Properties such as wall shear stress, dynamic yield stress relative viscosity are experimentally determined as functions of the electric field, for different particle concentrations and the shear strain rate under constant or free to vary temperature (due to operating conditions, angular velocity, friction). Concluding the ER fluids can be used to create “smart” journal bearings. Vibration controllers can be constructed to control the stability of the ER fluid lubricated bearings.

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45

Gao, Siyu, Kai Cheng, Shijin Chen, Hui Ding, and Hongya Fu. "Computational design and analysis of aerostatic journal bearings with application to ultra-high speed spindles." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231, no. 7 (November 14, 2016): 1205–20. http://dx.doi.org/10.1177/0954406216639344.

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Aerostatic bearings are the critical parts of ultra-high speed spindles applied to precision milling, grinding, and other precision engineering applications. In this paper, the computational design and analysis of aerostatic journal bearings at ultra-high speed spindles are investigated particularly in light of the nonlinear compressible Reynolds equation and the associated computational analysis and algorithms using the finite element method-based Galerkin weighted residual method. The steady-state static and dynamic behaviors of aerostatic journal bearings are systematically studied, including pressure distributions, load capacity, stiffness, attitude angle, and volume flow rate under conditions of various operating speeds and eccentricity ratios. The coupling of the aerostatic and aerodynamic effects within ultra-high speed aerostatic journal bearings is further explored. The obtained results are formulated as design guidelines for aerostatic journal bearings applied to air-bearing spindles operating in high precision and ultra-high rotational speeds.

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46

Wang, Tingting, Zhiwei Wang, Dongli Song, Weihua Zhang, Jiayuan Li, and De Chen. "Effect of track irregularities of high-speed railways on the thermal characteristics of the traction motor bearing." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 235, no. 1 (January 27, 2020): 22–34. http://dx.doi.org/10.1177/0954409720902359.

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The operating temperature plays a key role in the service reliability of ball bearings used in the traction motor of high-speed trains. Studies on the heat generation and temperature distributions of the bearing under the vehicle vibration environment are critical for designing the high-speed train traction motor bearing and to monitor its operation. In this paper, an SKF friction torque model that considers the inlet shear heating reduction and kinematic replenishment/starvation reduction was used to calculate the power loss of the bearing operating in a high-speed train. A thermal analysis model of the bearing, which takes into account the vehicle vibration due to track irregularities, was developed to study the thermal characteristics of the bearing operating in a high-speed train. Experiments were conducted on a service high-speed train (i.e. CRH380B) to validate the proposed bearing thermal analysis model. The thermal characteristics of the bearing and the influence of key factors on the operating temperature of the bearing under vehicle vibration due to track irregularities were studied with the proposed bearing thermal analysis model. The results show that the thermal failure of the bearing subassemblies most likely occurs at the balls region owing to the highest temperature in that region, compared to the inner and outer raceway of the bearing. The method of applying grease with appropriate kinematic viscosity should be adopted to reduce the power loss of bearing while meeting the lubrication requirement. The vehicle vibration due to track irregularities significantly influences the thermal characteristics of high-speed train motor bearings, which cannot be ignored in the thermal analysis of bearings operating in a high-speed train.

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47

Yuksel, E., E. Budak, E. Ozlu, A. Oral, F. Igrek, and F. Tosun. "PREDICTION OF THERMAL GROWTH IN A HIGH-SPEED SPINDLE BY CONSIDERING THERMO-MECHANICAL BEHAVIOR." MM Science Journal 2021, no. 3 (June 30, 2021): 4526–33. http://dx.doi.org/10.17973/mmsj.2021_7_2021055.

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Анотація:

Continuous rotation of spindle bearings and motor cause thermally induced structural deformations and thermal growth, which is one of the main reasons for machining errors. A positive feedback loop between bearing preload and heat generation causes preload variations in spindle bearings. These preload variations demonstrate a nonlinear transient behavior until the gradual expansion of outer bearing rings after which the thermally induced preload variation behaves steadily. In this study, a Finite Element (FE) framework is presented for predicting steady preload variation on spindle bearings. The method involves a thermal loading model and a transient contact analysis. In the contact analysis phase bearing contact deformations (penetration and sliding) and pressure are predicted by considering contact algorithms in an FE software. A transient spindle simulation in FE is employed to predict the bearing temperature and thermal spindle growth by using the proposed method. The performance of the method is demonstrated on a spindle prototype through bearing temperature and thermal deformation measurements. Results show that the proposed method can be a useful tool for spindle design and improvements due to its promising results and speed without the need for tests.

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48

Yu, Hai Bo, and Kun Wang. "Development of High Speed Motor with Magnetic Bearing." Advanced Materials Research 846-847 (November 2013): 44–47. http://dx.doi.org/10.4028/www.scientific.net/amr.846-847.44.

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In order to in-depth study the magnetic suspension molecular pump technology, a 4kW high speed magnetic motor was firstly developed. The magnetic motor includes 2 radial magnetic bearings, 2 axial magnetic bearing with five degrees of freedom. The wind abrasion and magnetic flux distribution in stators and the gap between the stator and the rotor were analyzed. Then the high speed magnetic motor prototype was introduced in detail. At last, the basic experiment result was present and the conclusions were given.

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49

Huang, Yu, Shang Zhang, Yi Lin Liu, Bi Peng, and Guo Jun Zhang. "Hydrostatic-Hydrodynamic Bearing Design of High-Speed Camshaft Grinding." Advanced Materials Research 590 (November 2012): 385–90. http://dx.doi.org/10.4028/www.scientific.net/amr.590.385.

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Conditions for changing acceleration and force spindle when the high-speed high-precision camshaft grinding with the action of follow grinding and the constant linear speed grinding，a step-pocket cavity hydrostatic -hydrodynamic bearings is designed to meet this precision camshaft grinding, and the relationship between eccentricity and bearing stiffness, load are analyzed by the method of finite-element analysis with fluid finite element analysis software.

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50

NISHIKAWA, Fumitaka, Shigeka YOSHIMOTO, and Kei SOMAYA. "3359 Ultra high speed micro-milling spindle directly supporting endmill shank by aerostatic bearings." Proceedings of International Conference on Leading Edge Manufacturing in 21st century : LEM21 2011.6 (2011): _3359–1_—_3359–4_. http://dx.doi.org/10.1299/jsmelem.2011.6._3359-1_.

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