scholarly journals Dynamic Behavior Analysis of the Winding Rotor with Structural Coupling and Time-Frequency Varying Parameters: Simulation and Measurement

2021 ◽  
Vol 11 (17) ◽  
pp. 8124
Author(s):  
Xunxun Ma ◽  
Shujia Li ◽  
Wangliang Tian ◽  
Xiqiang Qu ◽  
Shengze Wang ◽  
...  
Keyword(s):  
Dynamic Behavior ◽  
High Speed ◽  
Critical Speed ◽  
Rotation Speed ◽  
Frequency Dependent ◽  
Measuring Device ◽  
Time Frequency ◽  
Flexible Support ◽  
Coupling Structure ◽  
Speed Up

To satisfy the requirements of high speed, large capacity and constant winding, a textile winding rotor needs to work in a wide rotation speed range and frequently pass through critical speed points. Thus, the winding rotor adopts the flexible long shaft coupling structure and flexible support with rubber O-rings. This kind of rotor has a multi-coupling structure and frequency-dependent parameters characteristics, especially representative and universal in the dynamic analysis method of the high-speed rotor. In this paper, an approach was proposed to investigate the dynamic behavior of the winding rotor considering the flexible coupling and frequency-dependent supporting parameters. Firstly, a dynamic model of the winding rotor was established by using a Timoshenko beam element. Its dynamic behaviors were simulated by considering the time-varying rotation speed and the frequency-dependent parameters of flexible support. Secondly, a non-contact measuring device was developed for measuring the vibration displacement of the winding rotor in three different speed-up times. Finally, based on simulation and measurement data, how flexible support parameters and the speed-up time affect the winding rotor passing through the critical speed point of the rotor smoothly is revealed. The methods and findings reported here can be used for theoretical and experimental vibration analysis of other types of high-speed flexible rotors.

scholarly journals Dynamic of Friction Coupling Independently Rotating Wheels for High Speed

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Yan Shi ◽  
Miao Li ◽  
Weihua Ma ◽  
Kang Chen
Keyword(s):  
High Speed ◽  
Rotation Speed ◽  
Friction Pair ◽  
Large Radius ◽  
Coupling Structure ◽  
Lateral Coupling ◽  
Creep Force ◽  
Left And Right ◽  
Curved Track ◽  
Dynamics Models

A new lateral coupling structure with independently rotating wheels (IRW) is proposed, and longitudinal creepage is obtained by replacing the gear pair with the friction pair to synchronize the rotation speed of left and right wheels. The auxiliary wheelset made up of two friction wheels can be placed either under the primary suspension or on the frame. Vehicles dynamics models with three different kinds of bogies are developed, including friction coupling bogie with independently rotating wheels (FCIRW-bogie), bogie with independently rotating wheels (IRW-bogie), and bogie with rigid wheelsets, and their guiding and resetting capability when negotiating large-radius curves are compared and analyzed. Results show that FCIRW has the advantages of both IRW and rigid wheelset. On the straight track, FCIRW has sufficient wheel-rail longitudinal creep force to assist the reset; its critical speed is much higher than that of the rigid wheelset. On the curved track, the whole vehicle wear power of FCIRW-bogie vehicle is about 2/3 of the rigid axle level.

On interaction of a rolling stock and geometrical parametres of high-speed networks’ route

2017 ◽  
pp. 96-104
Author(s):  
Sergey Shkurnikov ◽  
Olga Morozova
Keyword(s):  
Dynamic Behavior ◽  
Simulation Modeling ◽  
High Speed ◽  
Practical Importance ◽  
Railway Vehicle ◽  
High Speed Train ◽  
Software Application ◽  
Speed Up ◽  
Passenger Trains ◽  
Universal Mechanism

Objective: Due to the lack of global experience of holding on one track high-speed passenger trains (moving at a speed up to 400 km/h), high-speed passenger trains (moving at a speed up to 250 km/h) and special freight trains (accelerating to a speed of more than 200 km/h), the only possible way of studying the influence of a train on a track is computer simulation modeling. The analysis of the existing computer programs was carried out and the most effective programme for the solution of combined train movement was selected. Methods: Simulation modeling was applied. On the basis of the obtained model the possibility of “Universal mechanism” software practical application was considered. Results: A test simulation model of a high-speed train carriage was developed in “Universal mechanism” software application. Preliminary results showed the possibility of its usage for the study of a high-speed train and track interaction. Practical importance: Modern computer technologies make it possible to solve the tasks of dynamic interaction with a high degree of accuracy. Among the variety of software used for the study of dynamic behavior of a railway vehicle in Russia, “Universal mechanism” software application is of wide popularity and may be used for the study of dynamic behavior of different types of trains on railway tracks of different plans and profiles.

Similarity Design of Rotary Machine’s Bearing Parameters

2009 ◽  
Author(s):  
Shenjian Su ◽  
Liming Wang ◽  
Ping Li ◽  
Jianli Zuo
Keyword(s):  
Dynamic Behavior ◽  
High Speed ◽  
Critical Speed ◽  
Parametric Optimization ◽  
Operating Speed ◽  
Dissipation Energy ◽  
Rotary Machine ◽  
Similarity Principle ◽  
The Difference ◽  
Pass Through

The bearing parameters, which dominate the dynamic behavior of the rotary machine, should be optimized so that the machine can successfully pass through the critical speed and stably run at the operating speed. However, the parametric optimization usually needs complicated numerical calculation and a great deal of experimentation, especially for the high-speed vertical machine studied here, the dynamic behavior of which is even more sensitive to the parameters. Whereas, the new-style rotor is of similar structure with the old-style rotor. The difference between the two types of rotors is that the new-style rotor’s length and diameter are 1.3 times of the old-style rotor. So it is feasible that the parametric optimization of new-style bearings is carried out by the similarity principle. The similarity principle is that the ratio between the new-style rotor’s whirl energy with the old-style rotor’s equals the ratio between the new-style rotor’s dissipation energy imposed by the bottom bearing with the old-style rotor’s when they run at the operating speed. The parametric optimization involved in this paper only needs simple numerical operation and a little experimentation and makes the new-style bearing parameters design much faster and cheaper than the old-style.

Design of an Experimental Setup for Testing Multiphysical Effects on High Speed Mini Rotors

2011 ◽  
Vol 133 (5) ◽  
Author(s):  
Emre Dikmen ◽  
Peter J. M. van der Hoogt ◽  
André de Boer ◽  
Ronald G. K. M. Aarts ◽  
Ben Jonker
Keyword(s):  
High Speed ◽  
Critical Speed ◽  
Rotation Speed ◽  
Design Procedure ◽  
Background Information ◽  
Small Scale ◽  
Experimental Setup ◽  
Research Projects ◽  
Design Decisions ◽  
Design Requirements

Recently, there have been numerous research projects on the development of minirotating machines. These machines mostly operate at speeds above the first critical speed and have special levitation systems. Besides, the multiphysical effects become significant in small scale. Therefore, advanced modeling approaches should be developed and innovative experimental rigs with the foregoing requirements should be constructed in order to test the developed techniques. In the current study, the design of an experimental setup for testing the multiphysical effects has been outlined. First, the previously developed multiphysical models (Dikmen, E., van der Hoogt, P., de Boer, A., and Aarts, R., 2010, “Influence of Multiphysical Effects on the Dynamics of High Speed Minirotors—Part I: Theory,” J. Vibr. Acoust., 132, p. 031010; Dikmen, E., van der Hoogt, P., de Boer, A., and Aarts, R., 2010, “Influence of Multiphysical Effects on the Dynamics of High Speed Minirotors—Part II: Results,” J. Vibr. Acoust., 132, p. 031011) for the analysis of small scale rotors are described briefly for background information. Second, an analysis of the effect of the rotor parameters (diameter, length, rotation speed, etc.) on the dynamics of the rotor under multiphysical effects is presented. Afterward the design process which includes the design decisions based on these results, the availability, simplicity, and applicability of each component is presented in detail. Finally, the experimental results have been presented and the efficiency of the design has been evaluated. In summary, the design requirements for an experimental setup for testing multiphysical effects on minirotors have been analyzed. The design procedure and evaluation of the design have been presented.

Micro Turbocharger on a Single Silicon Rotor

2004 ◽  
Author(s):  
P. Kang ◽  
S. Tanaka ◽  
M. Esashi
Keyword(s):  
High Speed ◽  
Journal Bearing ◽  
Rotation Speed ◽  
Bonding Temperature ◽  
Preliminary Test ◽  
Anodic Bonding ◽  
Thrust Bearings ◽  
High Speed Rotation ◽  
Speed Up ◽  
Speed Rotation

This paper describes the design, fabrication and preliminary test of a MEMS-based turbocharger. In this device, a compressor and a turbine are formed on the same side of the rotor to escape miss-alignment during bonding process. The rotor is supported by hydrostatic journal and thrust bearings. The device rotated only at low rotation speed up to 2500 rpm, and the rotation speed did not remarkably changed by adjusting air supplies to the hydrostatic bearings. From the test results, we found important issues to be solved for high speed rotation. Concerning to fabrication, flat and smooth bearing surfaces is difficult to fabricate, and bearing/tip clearances are difficult to precisely control due to spikes on etched surfaces and the warp of the devices induced by anodic bonding. We developed special deep RIE recipe to realize spike-free, uniform etching. And, we found that the wafer warp became negligible at a bonding temperature of 320 °C and an applied voltage of 400–600 V, when a 1 mm thick Pyrex glass substrate was used. Even after 5 times anodic bonding to stack 6 wafers, the warp was below 2 μm. The other concern is on bearing design. The journal bearing has a very low L/D number (length divided by diameter). As a result, the journal bearing has a small journal surface, and it is difficult to install orifices on the journal bearing. Additionally, there is interference between the journal and thrust bearing due to air leakage.

High speed railway track dynamic behavior near critical speed

2017 ◽  
Vol 101 ◽  
pp. 285-294 ◽  
Author(s):  
Yin Gao ◽  
Hai Huang ◽  
Carlton L. Ho ◽  
James P. Hyslip
Keyword(s):  
Dynamic Behavior ◽  
High Speed ◽  
Critical Speed ◽  
Railway Track ◽  
High Speed Railway

Scanning x-ray fluorescence microscopy and principal component analysis

1992 ◽  
Vol 50 (2) ◽  
pp. 1752-1753
Author(s):  
Brian Cross
Keyword(s):  
Principal Component Analysis ◽  
Fluorescence Microscopy ◽  
Spatial Resolution ◽  
High Speed ◽  
Image Acquisition ◽  
Principal Component ◽  
Fluorescence Microscope ◽  
Acquisition Rate ◽  
X Ray ◽  
Speed Up

A relatively new entry, in the field of microscopy, is the Scanning X-Ray Fluorescence Microscope (SXRFM). Using this type of instrument (e.g. Kevex Omicron X-ray Microprobe), one can obtain multiple elemental x-ray images, from the analysis of materials which show heterogeneity. The SXRFM obtains images by collimating an x-ray beam (e.g. 100 μm diameter), and then scanning the sample with a high-speed x-y stage. To speed up the image acquisition, data is acquired "on-the-fly" by slew-scanning the stage along the x-axis, like a TV or SEM scan. To reduce the overhead from "fly-back," the images can be acquired by bi-directional scanning of the x-axis. This results in very little overhead with the re-positioning of the sample stage. The image acquisition rate is dominated by the x-ray acquisition rate. Therefore, the total x-ray image acquisition rate, using the SXRFM, is very comparable to an SEM. Although the x-ray spatial resolution of the SXRFM is worse than an SEM (say 100 vs. 2 μm), there are several other advantages.

Ball bearing turbocharger vibration management: application on high speed balancer

2020 ◽  
Vol 21 (6) ◽  
pp. 619
Author(s):  
Kostandin Gjika ◽  
Antoine Costeux ◽  
Gerry LaRue ◽  
John Wilson
Keyword(s):  
Dynamic Behavior ◽  
High Speed ◽  
Internal Combustion Engines ◽  
Ball Bearing ◽  
Squeeze Film ◽  
Design And Technology ◽  
Squeeze Film Damper ◽  
Damping Coefficients ◽  
Bearing Loads ◽  
Stiffness And Damping

Today's modern internal combustion engines are increasingly focused on downsizing, high fuel efficiency and low emissions, which requires appropriate design and technology of turbocharger bearing systems. Automotive turbochargers operate faster and with strong engine excitation; vibration management is becoming a challenge and manufacturers are increasingly focusing on the design of low vibration and high-performance balancing technology. This paper discusses the synchronous vibration management of the ball bearing cartridge turbocharger on high-speed balancer and it is a continuation of papers [1–3]. In a first step, the synchronous rotordynamics behavior is identified. A prediction code is developed to calculate the static and dynamic performance of “ball bearing cartridge-squeeze film damper”. The dynamic behavior of balls is modeled by a spring with stiffness calculated from Tedric Harris formulas and the damping is considered null. The squeeze film damper model is derived from the Osborne Reynolds equation for incompressible and synchronous fluid loading; the stiffness and damping coefficients are calculated assuming that the bearing is infinitely short, and the oil film pressure is modeled as a cavitated π film model. The stiffness and damping coefficients are integrated on a rotordynamics code and the bearing loads are calculated by converging with the bearing eccentricity ratio. In a second step, a finite element structural dynamics model is built for the system “turbocharger housing-high speed balancer fixture” and validated by experimental frequency response functions. In the last step, the rotating dynamic bearing loads on the squeeze film damper are coupled with transfer functions and the vibration on the housings is predicted. The vibration response under single and multi-plane unbalances correlates very well with test data from turbocharger unbalance masters. The prediction model allows a thorough understanding of ball bearing turbocharger vibration on a high speed balancer, thus optimizing the dynamic behavior of the “turbocharger-high speed balancer” structural system for better rotordynamics performance identification and selection of the appropriate balancing process at the development stage of the turbocharger.

Formation of Standing Waves in Radial Tires

1984 ◽  
Vol 12 (1) ◽  
pp. 44-63 ◽  
Author(s):  
Y. D. Kwon ◽  
D. C. Prevorsek
Keyword(s):  
High Speed ◽  
Critical Speed ◽  
Unit Length ◽  
Standing Waves ◽  
Rolling Resistance ◽  
Damping Coefficient ◽  
Circular Membrane ◽  
Critical Speeds ◽  
Steel Cord ◽  
The Individual

Abstract Radial tires for automobiles were subjected to high speed rolling under load on a testing wheel to determine the critical speeds at which standing waves started to form. Tires of different makes had significantly different critical speeds. The damping coefficient and mass per unit length of the tire wall were measured and a correlation between these properties and the observed critical speed of standing wave formation was sought through use of a circular membrane model. As expected from the model, desirably high critical speed calls for a high damping coefficient and a low mass per unit length of the tire wall. The damping coefficient is particularly important. Surprisingly, those tire walls that were reinforced with steel cord had higher damping coefficients than did those reinforced with polymeric cord. Although the individual steel filaments are elastic, the interfilament friction is higher in the steel cords than in the polymeric cords. A steel-reinforced tire wall also has a higher density per unit length. The damping coefficient is directly related to the mechanical loss in cyclic deformation and, hence, to the rolling resistance of a tire. The study shows that, in principle, it is more difficult to design a tire that is both fuel-efficient and free from standing waves when steel cord is used than when polymeric cords are used.

scholarly journals Vibration of Rotating and Revolving Planet Rings with Discrete and Partially Distributed Stiffnesses

2020 ◽  
Vol 11 (1) ◽  
pp. 127
Author(s):  
Fuchun Yang ◽  
Dianrui Wang
Keyword(s):  
High Speed ◽  
Differential Operators ◽  
Natural Frequencies ◽  
Rotation Speed ◽  
Distribution Area ◽  
Vibration Modes ◽  
Governing Equations ◽  
Vibration Properties ◽  
Wide Range ◽  
Forced Responses

Vibration properties of high-speed rotating and revolving planet rings with discrete and partially distributed stiffnesses were studied. The governing equations were obtained by Hamilton’s principle based on a rotating frame on the ring. The governing equations were cast in matrix differential operators and discretized, using Galerkin’s method. The eigenvalue problem was dealt with state space matrix, and the natural frequencies and vibration modes were computed in a wide range of rotation speed. The properties of natural frequencies and vibration modes with rotation speed were studied for free planet rings and planet rings with discrete and partially distributed stiffnesses. The influences of several parameters on the vibration properties of planet rings were also investigated. Finally, the forced responses of planet rings resulted from the excitation of rotating and revolving movement were studied. The results show that the revolving movement not only affects the free vibration of planet rings but results in excitation to the rings. Partially distributed stiffness changes the vibration modes heavily compared to the free planet ring. Each vibration mode comprises several nodal diameter components instead of a single component for a free planet ring. The distribution area and the number of partially distributed stiffnesses mainly affect the high-order frequencies. The forced responses caused by revolving movement are nonlinear and vary with a quasi-period of rotating speed, and the responses in the regions supported by partially distributed stiffnesses are suppressed.

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