A study on the dynamic behavior of a skew bevel gear (1st report, On root stress ratio, torsional vibration, bending vibration of gear shaft, and vibrating displacements in three right-angled directions)

In certain rotor systems, bending-torsion coupled resonance occurs when the rotational speed Ω (= 2π Ωrps) is equal to the sum/difference of the bending natural frequency ωb (= 2π fb) and torsional natural frequency ωθ(= 2πfθ). This coupling effect is due to an unbalance in the rotor. In order to clarify this phenomenon, an equation was derived for the motion of the bending-torsion coupled 2 DOF system, and this coupled resonance was verified by numerical simulations. In stability analyses of an undamped model, unstable rotational speed ranges were found to exist at about Ωrps = fb + fθ. The conditions for stability were also derived from an analysis of a damped model. In rotational simulations, bending-torsion coupled resonance vibration was found to occur at Ωrps = fb − fθ and fb + fθ. In addition, confirmation of this resonance phenomenon was shown by an experiment. When the rotor was excited in the horizontal direction at bending natural frequency, large torsional vibration appeared. On the other hand, when the rotor was excited by torsion at torsional natural frequency, large bending vibration appeared. Therefore, bending-torsion coupled resonance was confirmed.

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Analysis of Coupled Bending-Axial Vibration of a Rotor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.662.608 ◽

2013 ◽

Vol 662 ◽

pp. 608-611 ◽

Cited By ~ 1

Author(s):

Jian Feng Ye ◽

Chun Long Zheng ◽

Xue Shi Yao

Keyword(s):

Axial Force ◽

Vibration Frequency ◽

Torsional Vibration ◽

Stiffness Matrix ◽

Tensile Force ◽

Vibration Frequencies ◽

Axial Vibration ◽

Bending Vibration ◽

Centrifugal Load ◽

Rotor Model

Aiming at a rotor model, the coupled bending-axial vibration is being analyzed.Calculation results show that the prestress relative to rotational centrifugal load may influence bending vibration frequencies of a rotor.The bending vibration frequencies will increase when the prestress increases.The axial vibration frequency has not an influence because the direction of the spinning prestress is perpendicular to axis.When a rotor is applies axial force, a compressional force will tend to increase the axial vibration frequencies while a tensile force will decrease the axial vibration frequencies.The effects of the prestress(centrifugal load )of the spinning rotor and the axial prestress can be accounted by an adjustment of the stiffness matrix for analysis.By use of the stiffness matrix,the changed axial and bending vibration frequencies can be explained.The coupled bending-axial vibration may take place when the bending vibration frequencies have increased in the state of the changed prestress.In the end, the coupled bending-axial vibration frequency can be calculated.On the basis of prestress, the coupled lateral-torsional vibration and the coupled torsional-axial vibration frequency can be analysed,similarly.

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An Experimental Study of Torsional Vibration Absorbers

Volume 6C: 18th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc2001/vib-21574 ◽

2001 ◽

Author(s):

Alan G. Haddow ◽

Steven W. Shaw

Keyword(s):

Experimental Study ◽

Dynamic Behavior ◽

Systematic Study ◽

Torsional Vibration ◽

Theoretical Background ◽

Controlled Environment ◽

Vibration Absorbers ◽

Test Apparatus ◽

First Time ◽

Theoretical Results

Abstract This paper presents results from tests completed on a rotor system fitted with pendulum-type torsional vibration absorbers. A review of the associated theoretical background is also given and the experimental and theoretical results are compared and contrasted. An overview of the test apparatus is provided and its unique features are discussed. To the best knowledge of the authors, this is the first time that a systematic study of the dynamic behavior of torsional vibration absorbers has been undertaken in a controlled environment.

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Study on Bending-Torsional Coupling Vibration of Intermediate Axis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.166-169.3180 ◽

2012 ◽

Vol 166-169 ◽

pp. 3180-3183

Author(s):

Xue Shi Yao ◽

Chun Long Zheng

Keyword(s):

Torsional Vibration ◽

Dynamic Equations ◽

Optimized Design ◽

Modal Shape ◽

Bending Vibration ◽

Coupling Vibration ◽

Centrifugal Load ◽

Torsional Coupling ◽

Nature Frequency ◽

Torsional Frequency

In order to find the cause of the cracked intermediate axis in a transmission,the characteristic of the bending vibration，torsional vibration and bending-torsional coupling vibration were studied through the analysis of the nature frequency and modal shape based on prestress.The results show that the fatigue fracture of the axis is mainly due to the resonant torsional frequency and bending-torsional coupling vibration and It is basically demonstrated by experiment.It has been found that the fundamental frequency is increase with the increase in spin axis velocity because of the centrifugal load i.e.prestress.The effets can be accounted for by an adjustment of the stiffness,and the dynamic equations are derived.In the end,it is made the optimized design on the axis,the low inherent frequencies are optimized in order to avoid resonance.The problem of the cracked intermediate axis has been solved.

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Optimization for the Dynamic Behavior of High Speed Spiral Bevel Gears

Volume 6: 8th International Power Transmission and Gearing Conference ◽

10.1115/detc2000/ptg-14395 ◽

2000 ◽

Author(s):

Zongde Fang ◽

Hongbin Yang ◽

Yanwei Zhou ◽

Xiaozhong Deng

Keyword(s):

Dynamic Behavior ◽

Contact Analysis ◽

Bevel Gear ◽

Spiral Bevel Gear ◽

Tooth Contact Analysis ◽

Tooth Contact ◽

Local Synthesis ◽

Wide Range ◽

Spiral Bevel ◽

Gear Drives

Abstract A new approach for optimizing the dynamic behavior of spiral bevel gear drives has been developed. The local synthesis, tooth contact analysis (TCA) and loaded tooth contact analysis (LTCA) techniques were used to constitute the design process with feedback, by which a contact ratio being near 2.0 or 3.0 would be achieved. An improved dynamic behavior of the spiral bevel gear drives under certain operating load or a wide range of load could be obtained.

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Analysis of Dynamic Behavior of Ultra-High Voltage Porcelain Arresters with New Type Lead Dampers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.625.61 ◽

2012 ◽

Vol 625 ◽

pp. 61-68

Author(s):

Xue Song Zhang ◽

Ze Bing Dai ◽

Zhi Cheng Lu ◽

Cheng Chen Cui

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Theoretical Analysis ◽

Dynamic Behavior ◽

Relative Displacement ◽

Element Analysis ◽

New Type ◽

Maximum Root ◽

Root Stress ◽

High Voltage Porcelain

Dynamic behavior of the 1100kV porcelain arresters with and without the new type lead dampers and are investigated，based on theoretical analysis and finite element analysis. The results of theoretical analysis show that the dynamic response of 1100kv porcelain arrester can be decreased by damping measures, which can change the dynamic behavior of equipment. The results of finite element analysis show that the primary frequencies of these two structures are between 1Hz and 10Hz and the differences between them is not obvious, which indicated that the overall stiffness of the two structures is low and the frequency and vibration mode of these two structures have hardly been changed by the lead dampers. The level modes dominated the equipment, while vertical modes and torsional modes are not obvious. Owning to an effect of increment of damping device with the new type lead dampers, there is a reduction by 40% above in the maximum root stress of porcelain bushing. In the meantime, the new type lead dampers can also decrease the relative displacement at the top of equipment.

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