Experimentally Validated Geometry Modification Simulation for Improving Noise Performance of CVT Gearbox for Vehicles

Zhen Qin,Qi Zhang,Yu-Ting Wu,Amre Eizad,류성기 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.11

Noise pollution has become one the most important environmental issues in modern life. The automobile, a product of the second industrial revolution, has a very large sales volume of approximately 100 million per year. With the popularity of automobiles, the noise generated by them has become a major cause of noise pollution. This paper presents an experimentally validated geometry optimization method for reducing the noise by a CVT gearbox used in motor vehicles. We used the CAE software RomaxDESIGNER to simulate the transmission error and the load distribution on meshing gear tooth surfaces before and after gearbox optimization. After determining the best modification values, we carried out a series of noise bench comparison tests to verify the simulation results. The test results confirmed that the optimization reduced the fluctuation in noise that occurred during certain speed stages of the gearbox. Due to the optimization, the overall noise level decreased and the noise curve became smoother.

A Study on Simulation Based Validation of Optimized Design of High Precision Rotating Unit for Processing Machinery

Zhen Qin,Yu-Ting Wu,Amre Eizad,전남술,김동선,류성기 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.9

With the rapid development of processing technology, the demand for precision, durability and NVH performance of processing machinery has also increased. This paper presents an optimally designed gear train composed of a set each of spiral bevel gears and spur gears to serve as a high precision rotating unit for processing machinery. The safety of each component used in the rotating unit gear train was verified using the geometry method and empirical formulae. The load contact pattern and PPTE value, which is an important indicator of the gear whine characteristic, were optimized using micro geometry modifications. In addition, the transfer efficiency of the entire gear train was determined and a novel dynamic analysis based on the comparison of the dynamic transmission error and the modal flexibility was performed to verify the correctness of the geometry design.

Design of anti-vibration mounting for 140A class alternator for vehicles

Zhen Qin,손형일,류성기 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.11

The alternator is a core component of modern vehicles that supplies power to all the electrical equipment when the engine is running. It is fitted to the engine bracket with long bolts going through the frame mountings. Due to the strong vibration from the engine, it is extremely important to improve its anti-vibration performance to extend the life of the alternator. This study presents a new anti-vibration mounting design for the alternator frame based on a 140A class alternator used in a best-selling sport utility vehicle (SUV). In this study, UG (unigraphics NX) was used to generate 3D models of the alternator and the finite element analysis software ABAQUS was used to simulate the vibration experiment. Then through a series of verification experiments, results were obtained which show that the new separated mounting design has obvious improvements in terms of the anti-vibration characteristic, as compared to the current design. The current work will be used for resonance reduction during design stages in future works.

Design and evaluation of two-stage planetary gearbox for special-purpose industrial machinery

Zhen Qin,Yu-Ting Wu,Amre Eizad,이기훈,류성기 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.12

The gearbox, as a traditional machine that changes the transmission ratio and transfers power safely, stably, quietly and efficiently, is an irreplaceable component in the field of machinery design. The planetary gear train is the most widely used of the traditional gearbox designs. Although scholars have carried out a variety of research on gearboxes, gear failures, noise and other issues are still common. This article presents a study involving the initial macro geometry design, gear flank modification, static and dynamic analysis, and experimental verification of a two-stage planetary gearbox for special-purpose industrial machinery. Compared to traditional static transmission error simulation, this study presents a novel analysis of the gearbox overall dynamic transmission error. In this research, the modal flexibility is also analyzed to determine the possibility of resonance in the gearbox. As a result, the strength of this gear system is guaranteed by macro design. PPTE (noise evaluation index) of each gear pair is greatly improved after flank modification. The efficiency of power transmission system is also improved with the improvement of vibration. The result of final bench test of the prototype is also quite satisfactory. This also verified the correctness of the theoretical simulation method presented in this research.

Advancement of Mechanical Engineering in Extreme Environments

Zhen Qin,Yu-Ting Wu,Amre Eizad,Sung-Ki Lyu,이춘만 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.6

With the continuing increase in the use of technology in the modern world, the environmental demands placed on mechanical products have become increasingly harsh, especially in the fields of industrial equipment, vehicles, robotics, medical equipment, and weapons . For the development of mechanical engineering, it is essential to ensure reliable performance, high efficiency, and long durability in extreme environments (extremes of temperature, pressure, corrosion, vibration, etc. ). The mechanical properties of the materials used to manufacture the components directly influence the component’s characteristics in extreme environments. Mechanical design and manufacturing processes are also key factors that affect the reliability of mechanisms. With the development of composite materials, computer technology, and the 4th industrial revolution, extreme environment technology has also progressed rapidly. Engineering for extreme environments is considered as a very important field in the green and environmental-friendly technology. This is because the shortened working life of machinery under such extremely harsh environments leads to higher energy consumption and more non-recyclable wastes. This paper reviews the developments related to novel extreme environment technologies in terms of materials, design, and manufacturing that have come about in recent years. Moreover, an analysis of related articles, patents, and the economy of this field is carried out and a perspective on the developmental trend is put forward.

Conceptual design for a multi-rotor UAV based on variable paddle pitch

Zhen Qin,Xiaoran Tang,Ziqi Meng,Yu-Ting Wu,류성기,Yue Wang 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.10

The field of unmanned aerial vehicles has experienced a "golden era" of progress in recent years (UAV). UAVs come in a vast variety, from the commercial to the military sectors. The UAVs available today are tiny, mini multirotor devices. The advantages of the small multi-rotor structure are its small size, straightforward design, high hovering effectiveness, adaptability in changing directions, and quick flight speed. For activities like tracking and aerial photography, it is especially useful. However, the majority of multi-rotor UAVs, according to current UAV offers, are built around cameras and sensors. As a result, they can't complete other kinds of missions due to their large overall size, light weight, and small cargoes. The outbreak has sparked interest in and study into whether contactless distribution and logistics are practical. Unmanned mechanical devices for various rescue and specialized duties are also being researched by organizations. Therefore, a medium to big multi-rotor UAV needs to be researched and developed. The assembly of paddle holders and auto-tilters for medium- to large-sized multi-rotor UAVs is examined in this work. The multi-rotor UAV is intended to mount an auto-tilter. Its component strength checks are analyzed. Additionally, the blade requirements are chosen, along with strength tests of the individual components, and the structural design of the UAV rotor system is provided. The mechanical viability of the UAV is then confirmed using a motion simulation of its mechanical design.

Design and Structural Stability Investigation of Novel Flat-Face Multi-coupling Systems for Hydraulic Power Equipment

Zhen Qin,Xiaoran Tang,Yu-Ting Wu,Sungki Lyu,Sang-Hu Park 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.23 No.10

Hydraulic power transmission systems have been widely used in recent years by virtue of their precise transmission, large driving force, safety, and reliability. Designs of hydraulic systems are being proposed that provide more convenient installation, greater driving force, and are more environmentally friendly. With this evolution, traditional hydraulic couplings are gradually becoming unable to meet the ever-changing hydraulic circuit connection requirements. In this paper, based on the fluid-structure interaction numerical investigation method and experimental verification methods, the construction safety and stability of the novel flat-face coupling system (NFFCS) is investigated, and the safety level of its construction stability is compared with that of a conventional flat-face coupling system. In addition, the mechanism design for 4-circuit and 6-circuit hydraulic quick coupling equipment based on the NFFCS technology is proposed, and the kinematic principles of its rapid and safe connection are explained. A series of structural stability simulations are implemented and the safety and reliability are discussed.

Transcriptome-wide identification of WRKY transcription factor and their expression profiles under salt stress in sweetpotato (Ipomoea batatas L.)

Qin Zhen,Hou Fuyun,Li Aixian,Dong Shuxu,Wang Qingmei,Zhang Liming 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.5

WRKY transcription factors play a key role in regulating plant growth, development, and stress responses. Although many WRKY transcription factors have been discovered in plants, the WRKY transcription factors in sweetpotato have not been systematically studied. Here, we identifed 79 IbWRKY transcription factors based on the transcriptome data of sweetpotato. The amino acid length of the protein ranged from 162 to 711 amino acids. Frequency analysis of amino acids in IbWRKY transcription factors found highest levels of serine. Subcellular localization analysis found 77 IbWRKY proteins localized in the nucleus. The IbWRKY proteins were clustered into three groups based on their structural and phylogenetic characteristics. Seven WRKY proteins contained the WRKY domain variations WRKYG(K/T)K as revealed by multiple sequence alignment. Structural analysis showed that IbWRKY proteins of the same subfamily had similar motifs. Transcriptome data analysis found that a total of 35 IbWRKY genes showed signifcant changes of the expression level after the 150 mM NaCl treatment. We selected 16 IbWRKY genes for real-time quantitative PCR verifcation and found that the data were consistent with the transcriptome data. In summary, this study provides a systematical analysis of the IbWRKY transcription factors, which will lay a solid foundation for further characterization of the regulatory mechanism of the IbWRKY genes under salt stress in sweetpotato.

A Review of Recent Advances in Design Optimization of Gearbox

Qin, Zhen,Wu, Yu-Ting,Lyu, Sung-Ki Springer-Verlag 2018 International Journal of Precision Engineering and Vol.19 No.11

Effect of power law on viscous fingering behavior of shear-thinning fluid in a lifted hele-shaw cell

Zhen Qin,Yu-Ting Wu,Chicheng Ma,류성기 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.7

This study examines the viscous fingering phenomenon of immiscible displacement in Hele-Shaw cells using the volume of fluid approach (HSC). The displaced fluid has various power law indices and is shear-thinning. Both the distribution properties of pressure and velocity were examined during the development process as well as the morphological evolution characteristics of non-Newtonian fluid when the air was moved. The findings indicate that pressure decreases in the fingering direction throughout the whole non-Newtonian fluid region. The non-Newtonian fluid's velocity close to the HSC pipe wall is virtually zero, and the highest velocity in the air phase is scattered throughout the finger's center. Its relative width gets less as development progresses. Viscous fingering then exhibits a high degree of stability and practically constant relative breadth. The outstretched fingers are shorter and thicker under different power-law indices, and the displacement efficiency is higher. The lower the power-law index n, the better the shear thinning properties. According to the aforementioned features, high-quality and high-efficiency oil displacement can be achieved in petroleum engineering by using new power rate fluid.