An Investigation on Dynamic Characteristics of a High Speed Rotor With Complex Structure for Microturbine Test Rig

2008 ◽  
Author(s):  
Di Zhang ◽  
Yonghui Xie ◽  
Zhenping Feng
Keyword(s):  
Temperature Field ◽  
Numerical Model ◽  
Dynamic Characteristics ◽  
Torsional Vibration ◽  
High Speed ◽  
Complex Structure ◽  
Rolling Bearing ◽  
Lateral Vibration ◽  
Test Rig ◽  
Turbine Impeller

During the research and development of 100kW class microturbine, a test rig with complex structure rotor for turbine impeller was constructed. Due to the limitation of test rig, the test rotor has to adopt cantilever configuration, which consists of shaft, connect disk with cool air holes, turbine impeller, and tie bar that joints the previous three components together. Because the rotor has a high rotational speed of 30000rpm, the ceramic rolling bearing is adopted for the test rig. In order to understand the dynamic characteristics of the rotor, a numerical model for temperature field has been developed using three dimensional finite element method firstly; then a numerical model to analyze the dynamic characteristics of high-speed ceramic rolling bearing and a numerical model to analyze the dynamic characteristics of the rotor considering the effect of temperature, shear deflection and gyroscopics have been developed too. At last, the temperature field and the dynamic characteristics of the test rig rotor were investigated in detail, some numerical results such as the critical speeds of lateral and torsional vibration, imbalance response, accelerate transient response were obtained. The numerical result of the first critical speed of lateral vibration shows good agreement with the experimental data, so the numerical model can provide accurate results for rotor dynamic analysis of such kind of rotor. Meanwhile, the critical speeds of lateral vibration and torsional vibration are far away from the operation speed of the rotor, and the response values are also very small, so that the rotor can operate reliably.

Development of Test Rig for High-Speed Railway Rolling Bearings

2011 ◽  
Vol 101-102 ◽  
pp. 702-707 ◽  
Author(s):  
Zhao Dong Huang ◽  
Bo Qian Fan ◽  
Xiao Ping Ouyang ◽  
Ling Ling Xu ◽  
Zhi Gang Wang
Keyword(s):  
High Speed ◽  
High Performance ◽  
Rolling Bearing ◽  
Main Shaft ◽  
Heavy Vehicles ◽  
Test Rig ◽  
Rolling Bearings ◽  
Heavy Load ◽  
High Speed Railway ◽  
Mechanical Structure

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.

Influence of Pocket Wear on the Dynamic Characteristics of High-Speed Ball Bearing Cage

2019 ◽  
Author(s):  
Hui Li ◽  
Chen Li ◽  
Yuan Li ◽  
Shemiao Qi ◽  
Yi Liu ◽  
...  
Keyword(s):  
Dynamic Model ◽  
Dynamic Characteristics ◽  
High Speed ◽  
Ball Bearing ◽  
Rolling Bearing ◽  
Outer Ring ◽  
Wear Loss ◽  
Vibration Modes ◽  
Mass Center ◽  
Fluctuation Amplitude

Abstract Aiming at the problem of wear on the cage-pocket during the operation of high speed rolling bearing, a dynamic model of high-speed ball bearing was established considering the wear loss of the ball-pocket, and the simulation was carried out to research on the interaction among the balls, the inner ring, the outer ring and the cage with different wear loss of the ball-pocket. The effect of the pocket wear on the trajectory of the cage’s mass center and the skidding ratio of cage was obtained. It was found out that the mass-center trajectory of the cage presents two vibration modes with different amplitudes which emerges alternatively. Moreover, the wear loss of the ball-pocket has little effect on the average skidding ratio of the cage, however, the fluctuation amplitude would become larger as the wear increase. This study can provide theoretical guidance for the design of bearing cage pocket size.

The Comparison of Four Pressure-Thermal Models of Oil Film Bearing With the Non-Newtonian and Temperature-Viscosity Effects

2016 ◽  
Author(s):  
Feng Liang ◽  
Quanyong Xu ◽  
Xudong Lan ◽  
Ming Zhou
Keyword(s):  
Temperature Field ◽  
Numerical Model ◽  
High Speed ◽  
Reynolds Equation ◽  
Pressure Field ◽  
Journal Bearing ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Oil Film ◽  
Viscosity Effects

The thermohydrodynamic analysis of oil film bearing is essential for high speed oil film bearing. The temperature field is coupled with the pressure field. The numerical model can be built or chosen according to the complexity of the objects and requirement of the accuracy. In this paper, four pressure-thermal (P-T) models are proposed, which are zero-dimensional temperature field coupled with Reynolds equation (0D P-T model), two-dimensional temperature field coupled with Reynolds equation (2D P-T model), two-dimensional temperature with third dimensional correction coupled with Dawson equation (2sD P-T model), three-dimensional temperature field coupled with Dawson equation (3D P-T model). The non-Newtonian and temperature-viscosity effects of the lubrication oil are considered in all the four models. Two types of cylindrical journal bearing, the bearing with/without axial grooves, are applied for the simulation. All the simulated cases are compared with the solutions of the CFX. The results show that the 0D P-T model fails to predict the behavior of high speed bearing; The 2D and 2sD P-T model have an acceptable accuracy to predict the performance of the bearing without grooves, but are not able to simulate the P-T field of the bearing with grooves because of the under-developed thermal boundary layer; The 2sD P-T model shows a great improvement when calculating the pressure field compared with the 2D P-T model; the 3D P-T model coincides well with the CFX at any condition. The comparison of these four models provides a reference to help designer choose a proper numerical model for a certain project.

System Design of Spindle on High-Precise CNC

2012 ◽  
Vol 151 ◽  
pp. 463-468 ◽  
Author(s):  
Jun Feng Wang ◽  
Xian Feng Du ◽  
Qing Ming Hu ◽  
Shi Gang Wang
Keyword(s):  
Dynamic Characteristics ◽  
High Speed ◽  
Rapid Development ◽  
Rolling Bearing ◽  
Spindle Motor ◽  
Production Equipment ◽  
Direct Drive ◽  
Static And Dynamic Characteristics ◽  
Radial Bearing ◽  
Accuracy And Stability

With the rapid development of science and technology, Lathe will be sure to develop in the direction of high speed, high precision and high stability as the most basic and important production equipment in industry. The spindle is the one of important component in the lathe, of which static and dynamic characteristics is directly related to the machining precision and machining stability, and the performance of spindle system directly affects the overall machine specifications. Through the analysis of the characteristics of spindle, the ways and means of the spindle analysis are studied. For the requirements of static and dynamic characteristics analysis in the process of spindle design on high-precise CNC lathes hydrostatic, direct-drive spindle motor mode is used. Three-supporting structure is adapted in the layout of spindle bearing in order to improve the accuracy and stability of the spindle drive. The rolling bearing is used in auxiliary support, the front and rear radial bearing is used in master hydrostatic bearing. Thrust bearings are located on both sides of the former type of radial bearing to complete the selection of the spindle material and the design of the structural primary dimensions. It is meaningful to improve the specifications of CNC lathes, guide the design, generation and modification of the high precise CNC lathe and enhance static dynamic characteristics of the spindle and improve accuracy and stability of the machine tool processing.

A high-speed rolling bearing test rig supported by sliding bearing

2020 ◽  
Vol 72 (7) ◽  
pp. 955-959
Author(s):  
Hui Li ◽  
Heng Liu ◽  
Shemiao Qi ◽  
Yi Liu
Keyword(s):  
Service Life ◽  
Peer Review ◽  
High Speed ◽  
Load Capacity ◽  
Rolling Bearing ◽  
Test Rig ◽  
Sliding Bearing ◽  
Content Type ◽  
Rotating Speed ◽  
Operating Stability

Purpose The purpose of this paper is to introduce a high-speed rolling bearing test rig supported by sliding bearing and its first experimental results. Design/methodology/approach Through analyzing the disadvantages of using rolling bearing as supporting bearing, the bottlenecks that need to be resolved urgently in the development of rolling bearing experimental technology, and the advantages of the sliding bearing, this study used the sliding bearing as the supporting bearing for the high-speed rolling bearing test rig for the purpose of prolonging the service life, increasing the load capacity and promoting the operating stability. Findings The experimental results show that the high-speed rolling bearing test rig supported by sliding bearing could stably rotate at 70,800 rpm without installing the test bearing; the temperature of the sliding bearing is increasing with the rotating speed and the maximum is less than 95°C. Moreover, the new test rig, installing an angular contact ball bearing as test bearing, could also stably rotate at 54,000 rpm with 2 kN axial load and 1 kN radial load; the temperature of the sliding bearing is increasing with the rotating speed and the maximum temperature is less than 97°C. Practical implications Rolling test rig has been established. Originality/value This paper proposes a high-speed rolling bearing test rig supported by sliding bearing, which greatly prolongs the service life, increases the load capacity and promotes the operating stability, moreover, reduces the risk of supporting bearing failure before the test bearing. This paper can also provide a new idea and reference for the design of similar bearing test rig. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2020-0085/

scholarly journals NEW BEARING STEEL FOR HIGH-SPEED APPLICATIONS

2021 ◽  
Vol 2021 (6) ◽  
pp. 5334-5339
Author(s):  
CHRISTIAN BRECHER ◽  
◽  
STEPHAN NEUS ◽  
MARCUS GAERTNER ◽  
LEONARDO CATANA ◽  
...  
Keyword(s):  
High Speed ◽  
Rolling Bearing ◽  
Bearing Steel ◽  
Performance Limits ◽  
Test Rig ◽  
Good Resistance ◽  
Surface Fatigue ◽  
Bearing Steels ◽  
Spindle Bearing ◽  
Contact Pressures

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.

Numerical Model Updating Technique for Estimating Load Carrying Capacities of High Speed Railway Bridges

2016 ◽  
Vol 106 (8) ◽  
pp. 490-497
Author(s):  
Dong-Uk PARK ◽  
Jae-Bong KIM ◽  
Nam-Sik KIM ◽  
Sung-Il KIM
Keyword(s):  
Numerical Model ◽  
High Speed ◽  
Model Updating ◽  
High Speed Railway ◽  
Railway Bridges ◽  
Load Carrying
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