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Thermal Management and Dynamic Performance of a Cooler design for the Supercritical CO2 Turbine Shaft Cooling

FRONTIERS IN ENERGY RESEARCH 2022年 10卷

作者： Li, Jun Gurgenci, Hal Guan, Zhiqiang Li, Jishun Xue, Yujun Li, Lun School of Mechatronics Engineering Henan University of Science and Technology Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang China School of Mechanical and Mining Engineering University of Queensland Brisbane QLD Australia

This paper presents the results of a numerical study on a supercritical CO2 (SCO2) turboshaft cooling device by considering heat transfer and hydrodynamics. A micro-cooling device with a radius clearance of 50 micron and a nozzle diameter of 4 mm was designed and used to investigate the heat transfer characteristics of a micro-spacing impinging and gas film dynamics. Sixteen nozzles (N = 16) are equally spaced around the shaft in single or double rows. Investigations include journal speed- and eccentricity-dependent forward and cross-coupled force coefficients, and the effects of nozzle layouts and mass flow rate on the heat transfer efficiency. Analysis of the correlation coefficient shows that the gas density in the radial clearance is the dominant factor affecting the convective heat transfer performance, while the fluid velocity is a secondary factor. And the cooling efficiency (mass flow utilization rate) at low cooling pressure (p(s) < 0.7 MPa) is significantly greater than that at high cooling pressure (p(s) > 0.7 MP). In addition, considering the structure alone, a dual-row cooler exhibits a higher average Nusselt number, also registers a higher mass flow rate at the same pressure. Once the shaft is heated only one end, the difference in effectiveness between single- and dual-row cooling is not significant, so coolers with a single-row configuration should be preferred. Then, experimental values for the temperature of the heated rotor are provided under specific cooling airflow conditions. Dynamic analysis results show that the force coefficient of the single-row configuration is more dependent on the journal rotation speed and eccentricity ratio, and exhibits a negative direct stiffness coefficient at higher inlet pressure and journal rotation speed. Moreover, cross-coupled terms (stiffness coefficient) generally have a more explicit variation tendency than direct terms, and are more sensitive to changes in shaft speed and eccentricity. Small clearance cool

关键词： shaft cooling gas film stiffness heat transfer cooler jet impingement

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Line laser measurement, evaluation and utilization of holistic gear deviations

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Measurement: Sensors 2025年

作者： Shi, Zhaoyao Sun, Yanqiang Yu, Bo Wang, Xiaoyi Zhao, Baoya Beijing Engineering Research Center of Precision Measurement Technology and Instruments Beijing University of Technology Beijing China School of Construction Machinery Shandong Jiaotong University Shandong Jinan China Henan Key Laboratory of Mechanical Design and Transmission System Henan University of Science and Technology Luoyang China School of Mechatronics Engineering North China Institute of Aerospace Engineering Langfang China

The measurement of holistic gear deviations (HGD) is a fast-developing field of gear measurement technology in recent years. Line laser measurement is an effective approach to measure the HGD, and is beginning to be applied. However, compared with the mature conventional gear measurement based on "point" and "line" measurement, the holistic gear deviations measurement is imperfect, especially in acquisition, evaluation and utilization. This paper introduces the line laser measurement model of HGD and puts forward the solutions to the problems such as the determination of the position and attitude parameters of the laser sensor, the influence of the incident angle of the measuring light, and the occlusion of the adjacent gear teeth in the measurement. The representation method of the three-dimensional deviations of the tooth flank is illustrated. According to the HGD, a unified model for calculating the elemental deviations of the gear, such as the involute and helix, is found. The HGD evaluation system is established by means of the statistical analysis method. The full use of the HGD is explored from two aspects of gear process error analysis and gear performance prediction, including tooth flank twist analysis, calculation of gear integrated error (GIE) and transmission error (TE), matching method of large batch of gears, etc. The analysis system of HGD is built on the cloud platform. The measurement, evaluation and utilization of HGD are the key technologies of the next generation gear measurement. © 2025

关键词： Metrology Gear Holistic gear deviations

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Time-dependent fatigue reliability estimation and optimal design of scraper chains under corrosive wear effect

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Mechanics Based design of Structures and Machines 2024年第10期52卷

作者： Shuai Li Zhencai Zhu Hao Lu Yujun Xue Gang Shen a School of Mechatronics Engineering Henan University of Science and Technology Luoyang Chinab Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang Chinac Longmen Laboratory Luoyang China d School of Mechatronic Engineering Jiangsu Key Laboratory of Mine Mechanical and Electrical Equipment China University of Mining and Technology Xuzhou China

Fatigue damage is one of the main failures of the scraper chain. Moreover, corrosive wear has a detrimental effect on fatigue crack propagation. It is so essential to study the fatigue reliability of the scraper chain considering the interaction of corrosive wear and fatigue. This paper is intended to propose a reliability-based estimation and optimal design of the scraper chain considering the performance degradation of the scraper chain under the interaction of corrosive wear and fatigue. First, the dynamic model of the scraper conveyor is established based on the finite element method. Second, Paris Low is used to empirically describe the occurrence of cracking with corrosion effects. Furthermore, the time-dependent reliability of scraper chains under the interaction of the corrosive wear and fatigue crack propagation is addressed by the fourth-moment saddlepoint approximation (FMSA) method, and the reliability-based design optimization (RBDO) of the scraper chain is then carried out. Finally, the applicability of the proposed method is verified by the SGZ1000/1400 scraper conveyor.

关键词： Fatigue reliability scraper chain saddlepoint approximation reliability based design optimization

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Tension Characteristics Analysis of Scraper Chain of Heavy-Duty Scraper Conveyor with Time-Varying Loads

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Shock and Vibration 2024年第1期2024卷

作者： Shuai Li Zhencai Zhu Hao Lu Yujun Xue School of Mechatronics Engineering Henan University of Science and Technology Luoyang 471003 China *** Henan Key Laboratory for Machinery Design and Transmission System Luoyang 471003 China Collaborative Innovation Center of Henan Province for High-End Bearing Henan University of Science and Technology Luoyang 471000 China *** Longmen Laboratory Luoyang 471000 China School of Mechatronics Engineering Jiangsu Key Laboratory of Mine Mechanical and Electrical Equipment China University of Mining and Technology Xuzhou 221116 Jiangsu China ***

With the intensification and large scale of coal mining, scraper conveyors are developing towards high power, large volume, long haul distance, and high reliability. It is more and more important to obtain the dynamic tension of the scraper chain with time-varying loads. The purpose of this paper is to obtain the dynamic tension of scraper chains of the scraper conveyor with time-varying loads. First, according to the structural characteristics and working environment of the scraper conveyor and the polygon effect of the sprocket, the scraper conveyor dynamic model under the action of the time-varying loads is established by the finite unit method. Second, the load variation rule of the bearing section is explored when the scraper conveyor and shearer work together. Furthermore, the element resistance of each discrete element, the stiffness coefficient of the scraper chain, and the influence of polygonal effect of sprocket wheel are analyzed. And then, the dynamic tension of the scraper chain is obtained by the Hilber–Hughes–Taylor (HHT) method. Finally, the validity of the scraper conveyor dynamic model is verified by the example analysis and field measurement experiment. Due to the influence of heavy starting, the maximum tension of the scraper chain during the starting process is 751.6 kN, which is 12.25% higher than the tension with smooth running (669.6 kN). During the startup stage, significant impacts occur on both motors and scraper chains which may lead to damage. To protect these components effectively, control strategies such as “soft start” or no-load start hold crucial engineering significance in achieving reliable operation of the scraper conveyor. The obtained results can provide a theoretical basis for the reliability evaluation and parameter optimization of the scraper conveyor.

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Research on active disturbance rejection control method for electro-hydraulic servo loading system with considering clearance disturbance 8

Research on active disturbance rejection control method for ...

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8th IEEE International Conference on Fluid Power and Mechatronics, FPM 2019

作者： Chen, Qiang Yang, Fang Liu, Dan-Dan Xue, Yu-Jun Henan University of Science Technology School of Mechatronics Engineering Luoyang China Henan University of Science Technology Henan Key Laboratory of Mechanical Design and Transmission System Luoyang China Luoyang LYC Rearing Co. Ltd Luoyang China

ISBN: (纸本)9781728103112

In the test of high-speed rail bearings, the electro- hydraulic servo-loading system is commonly used to simulate the actual alternating loading for the bearing. Due to the existence of the loading mechanism clearance and the transmission shaft system matching clearance, the loading system has a certain nonlinear displacement disturbance. Combined with the nonlinear characteristics of the electro-hydraulic servo system, the dynamic response characteristics and steady-state control accuracy of the force loading are seriously affected. To this end, the Active Disturbance Rejection control (ADRC) method is used to identify and compensate the gap disturbances using the feedback information of the extended state observer, and the tracking differentiator and feedback control rate are designed to improve the system response speed and suppress overshoot. The control method is applied to the control model of high-speed rail bearing electro-hydraulic servo-loading system. The simulation results show that the control method can achieve good control effect, and the anti-disturbance capability, response speed and steady-state performance of the system are significantly improved. © 2019 IEEE.

关键词： Disturbance rejection

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Research on power characteristics matching of electric drive crawler bulldozer 3

Research on power characteristics matching of electric drive...

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3rd IEEE International Conference on Electronic Information Technology and Computer Engineering, EITCE 2019

作者： Lun, Li Du, Bo-Feng Yang, Shao-Dong Li, Ji-Shun Henan University of Science and Technology Henan Key Laboratory for Machinery Design and Transmission System Luoyang471003 China Shenzhen Zhaowei Machinery and Electronics Co. Ltd. Shenzhen518105 China Mechanical and Electrical Equipment Engineering Co. Ltd Luoyang471003 China

ISBN: (数字)9781728135847

ISBN: (纸本)9781728135847

According to the composition of the electric drive system of the electric drive crawler bulldozer, the basic parameters of the main components in the electromechanical transmission system were calculated by using theoretical knowledge. The original and improved electric drive crawler bulldozer were simulated and compared respectively by using ADVISOR simulation software in order to verify the power performance of the improved electric drive crawler bulldozer. The studying result shows that the improved drive motor can meet the load characteristics of the crawler bulldozer under the bulldozing conditions through theoretical analysis and simulation research, and the improved electric drive system can meet the power characteristics of the D320E electric drive crawler bulldozer. © 2019 IEEE.

关键词： Computer software

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Research on Active Disturbance Rejection Control Method for Electro-hydraulic Servo Loading system with Considering Clearance Disturbance

Research on Active Disturbance Rejection Control Method for ...

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International Conference on Fluid Power and Mechatronics (FPM)

作者： Qiang Chen Fang Yang Dan-dan LIU Yu-jun Xue School of Mechatronics Engineering Henan University of Science & Technology Luoyang China Henan Key Laboratory of Mechanical Design and Transmission System Henan University of Science & Technology Luoyang China Luoyang LYC Rearing Co. Ltd Luoyang China

ISBN: (数字)9781728103112

ISBN: (纸本)9781728103129

关键词： Loading Force Servomotors Laser excitation Electron tubes Hydraulic systems Pressure sensors

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Study on Processing Process of SiC Single Crystal Cut with Wire Saw Excited by Ultrasonic

Study on Processing Process of SiC Single Crystal Cut with W...

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International Conference on mechanical, Control and Computer Engineering (ICMCCE)

作者： Lun Li Shaodong Yang Bofeng Du Shiyu Xu Jishun Li Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang China Zhongqi Changxing (Luoyang) Mechanical and Electrical Equipment Engineering Co. Ltd. Luoyang China Shenzhen Zhaowei Machinery & Electronics Co. Ltd. Shenzhen China

ISBN: (数字)9781728146898

ISBN: (纸本)9781728146904

Owing to high hardness and brittleness, SiC single crystal is the typical difficult-to-machine material. The SiC single crystal workpiece was cut by wire saw excited by transverse ultrasonic, and the cutting process was analyzed in current research. The kinematics equation of ultrasonic excitation wire saw and ordinary wire saw were established, and two different kinematics characteristics were analyzed respectively. The trajectory of abrasive particles in two cutting mode changed fundamentally. The finite element simulation model of single diamond abrasive cutting SiC single crystal was established. The influence of processing parameters on sawing force, surface morphology of SiC single crystal cut with abrasive excited by ultrasonic and ordinary diamond abrasive cutting was analyzed. The results show that sawing force of diamond abrasive excited by ultrasonic is much less than that of ordinary diamond abrasive cutting and the surface morphology is fairly flat. The cutting depth of abrasive has a significant influence on the sawing force and wafer surface.

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Research on motion error of cylindrical roller bearings under radial load

Research on motion error of cylindrical roller bearings unde...

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ASME 2018 International design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE 2018

作者： Yongjian, Yu Jishun, Li Guoding, Chen Yujun, Xue Zhuoyi, Si Gurgenci, Halim Henan Key Laboratory for Machinery Design and Transmission System Henan University of Science and Technology Luoyang Henan China School of Mechanical Engineering Northwestern Polytechnical University Xi’an Shanxi China School of Mechatronics Engineering Henan University of Science and Technology Luoyang Henan China School of Engineering University of Queensland BrisbaneQLD Australia

ISBN: (纸本)9780791851791

Since the rotary motion of a rolling bearing is implemented by bearing components under geometric constraints, the motion accuracy of an assembled bearing should also be the result of interaction among geometric errors of bearing components. Therefore, it is significant to understand the relationship between the geometric errors of bearing components and motion accuracy of an assembled bearing for the design of high accuracy bearing. Based on quasi-static analytical method, a mathematical model for motion error of cylindrical roller bearings is established considering the roundness error of outer raceway. The motion error of a rolling bearing is affected by the amplitude and harmonic order of the roundness error of outer raceway, number of rollers and the operating conditions such as radial load, rotary speed of outer ring. The effects of above parameters are analyzed. The results show that the motion accuracy of a cylindrical roller bearing degrades with the increase of amplitude of the roundness error of outer raceway and the rotary speed of outer ring. The variation of the radial displacement of outer ring varies periodically with the increase of the harmonic order of the roundness error of outer raceway, and its period is equal to the roller number. With the increase of the roller number, the variation of radial displacement of the outer ring fluctuates. The larger the radial load is, the smaller the variation of radial displacement of outer ring is. The results would be helpful to reduce the production costs by controlling the distribution of machining tolerance of bearing components. Copyright © 2018 ASME

关键词： Rollers (machine components)

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Research on Rotational Accuracy of Cylindrical Roller Bearings

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Procedia CIRP 2017年 62卷 380-385页

作者： Yu Yongjian Chen Guoding Li Jishun Xue Yujun School of Mechanical Engineering Northwestern Polytechnical University Xi’an 710072 China Henan Key Laboratory for Machinery Design and Transmission System Luoyang 471003 China School of Mechanical Engineering Henan University of Science and Technology Luoyang 471003 China

To investigate transferring mechanism of form error of bearing elements and rotational accuracy in cylindrical roller bearings, according to the bearing components motion and geometric relationships, a prediction model for rotational accuracy of cylindrical roller bearings based on roundness error of the inner raceway is presented. The effects of roundness error (i.e., amplitude, order) in the inner raceway, the number of rollers and radial clearance on the radial runout of inner ring are analyzed. Analytic solutions of the radial runout of inner ring are deduced when shapes of bearing elements are an ideal circle, which verifies the correctness of the presented model. The results show that the proposed model has better precision accuracy.

关键词： Cylindrical roller bearing Rotational accuracy Radial runout Roundness error Form error

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