A modern, high-quality and comprehensive national transport network is being developed to enhance public well-being. The development of national railways always comes under the spotlight in China. High-speed railways are weaving booming cities and counties across the country into beautiful “ecological galleries”. Reducing the vibration and noise generated by high-speed trains is a thorny challenge worldwide, and also a topic that cannot be ignored in the construction of high-speed railways. Numerous researchers have devoted themselves to research for many years, just to reduce another decibel. Prof. SHENG Xiaozhen has devoted himself to research in this field for more than 30 years, trying to make high-speed railways a little quieter.
“We must race against time to achieve breakthroughs in key technologies. Winter and summer vacations are prime time to do scientific research. It will be more fulfilling to spend the Spring Festival in the lab,” said Prof. SHENG Xiaozhen. During the winter vacation, Prof. SHENG Xiaozhen and his team members are busy all day long either at the engineering site or in the laboratory. With solid theoretical foundation and rich practical experience, the team members have conducted in-depth research on vibration and noise of rail transit systems to solve technical problems in related industries.
Racing against time to ensure that national projects are advanced as scheduled During the winter vacation, the joint fund project for high-speed railways and the international cooperation project under the National Key R&D Program of the Ministry of Science and Technology, both of which were chaired by Prof. SHENG Xiaozhen, were carried out in an orderly manner. The project has brought together top experts in the field of railway noise from the University of Southampton in the UK, and Southwest Jiaotong University and Tongji University in China. They studied the generation mechanism, propagation law and control measures of high-speed railway noise, as well as the key technologies of vibration and noise reduction of high-speed railways under complex conditions. Twice a week, Prof. SHENG Xiaozhen hosted discussions online to keep abreast of the progress of the partners, and led the experts to jointly tackle key problems to ensure that the project was implemented as scheduled. Assembling quickly to address technical bottlenecks “The accurate measurement of vibration of rotating parts is a technical problem that plagues us and needs to be solved urgently!” A technical leader from an internationally renowned turbocharger company eagerly asked Professor Sheng for help. Professor Sheng took on the challenge. He called on experts including those from the State Key Laboratory of Traction Power at Southwest Jiaotong University to quickly set up a working group on test methods for vibration of rotating parts based on acoustic signals. The team members immediately started the research, established the theoretical prediction model, wrote the signal analysis program, and carried out the experimental verification. Thanks to the fruitful research results, it has become feasible to accurately assess vibration levels based on acoustic signals, providing the client with new and effective testing methods and significantly shortening product testing cycles and reducing costs.
Rising to the challenge to make high-speed railways a little quieter Wheel-rail vibration and noise are hot topics and tough challenges in the field of rail transit. In 2020, China issued the Opinions on Accelerating the Development of Metropolitan (Suburban) Railways. In the Beijing-Tianjin-Hebei region, the Guangdong-Hong Kong-Macao Greater Bay Area, and the Yangtze River Delta, a large number of urban railways will be built soon. Are existing vibration and noise EIA methods appropriate? How far should buildings be from the railway? Are the measures for vibration and noise reduction of subway tracks applicable? In response to these urgent problems, during the winter vacation, the team led by Prof. SHENG Xiaozhen, at the request of the Urban Rail Transit Design and Research Institute of China Railway Engineering Design Consulting Group, carried out systematic and comprehensive theoretical research on the generation mechanism, transmission characteristics and influencing factors of vibration and noise of wheel rails at the speed of 120~250km/h. They set two goals: firstly, developing a quantitative prediction method and analysis software for wheel-rail vibration and noise at a speed of 120~250km/h; secondly, proposing a guide book on comprehensive vibration and noise reduction technology applicable to urban rail transit in the new era at different speed levels to provide theoretical basis for vibration and noise reduction of urban (suburban) railways. Imparting knowledge and educating students “You are very busy, and I can’t keep an eye on you every day. Now that we are on vacation, I can teach you.” “While theory is important, practice is also essential. I will show you how to do it. I hope you will practice during the vacation,” Prof. SHENG Xiaozhen said to his graduate students at a regular meeting. He patiently instructs the graduate students in even basic aspects such as formula derivation, program writing error checking, and result analysis. He takes the graduate students to the engineering site and instructs them in practice. Prof. SHENG Xiaozhen is caring for the graduate students and meticulous in scientific research. He is greatly admired by all his graduate students. They threw themselves into study and research at full speed. In the past year alone, his graduate students published 8 papers in top Chinese and international journals.
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