coming! The fastest high-speed railway in the world. On December 29th, the CR450 high-speed train prototype was officially released in Beijing. The test speed of the high-speed train can reach 450 kilometers per hour, and the operating speed can reach 400 kilometers per hour. What high-tech does the CR450 high-speed train contain? What new experience will it bring? High speed rail technology leads the world, how can Chinese railways achieve it? What does the CR450 high-speed train rely on to increase its speed by 50 kilometers per hour while maintaining the same braking distance, energy consumption, and noise? Stronger power - as we all know, high-speed trains run faster by converting electrical energy into mechanical energy. In order to improve the efficiency of energy conversion, the CR450 high-speed train adopts permanent magnet traction motors, which increase the conversion efficiency by more than 3% compared to the asynchronous traction motors of the CR400 high-speed train. Less resistance - For high-speed trains, aerodynamic resistance increases with the square of speed. When accelerating to a speed of 400 kilometers per hour, resistance increases by 30%. It can be said that most of the energy generated by the traction motor is consumed in the "confrontation" with the air. By optimizing the design, the CR450 high-speed train achieved a 22% reduction in overall running resistance. Lightweight - When traveling on high-speed trains, it is crucial to travel with light equipment. By using new materials such as carbon fiber composite materials and magnesium alloys, and applying topology optimization technology, the CR450 high-speed train has reduced its weight by more than 10% compared to previous models. Better performance - for high-speed trains, they run faster and have to be able to stop. From a speed of 400 kilometers per hour to 0, the CR450 high-speed train only requires 6500 meters. This number is consistent with the braking distance of the CR400 high-speed train, achieving an increase in operating speed while maintaining the same braking distance. It is precisely with these excellent performances that the CR450 high-speed train can achieve a speed increase of 50 kilometers per hour without changing energy consumption. The 8-car CR450 high-speed train consumes only 22 to 23 kilowatt hours of electricity per kilometer at a speed of 400 kilometers per hour, ensuring its economic and green operation for commercial use. The CR450 high-speed train also has many eye-catching designs: more intelligent. The CR450 high-speed train is equipped with an intelligent monitoring and diagnostic system, which collects real-time data on axle temperature, pressure, etc. from over 4000 monitoring points throughout the train, achieving self sensing, self diagnosis, and self decision-making. Not only that, the CR450 high-speed train innovatively uses a time sensitive network to transmit signals, which improves real-time transmission performance by 10 times. The use of time sensitive networks enables more timely information exchange and higher control accuracy between various systems of high-speed trains, "said Zhao Hongwei, Chief Researcher of the China Academy of Railway Sciences Group. More silent. Noise directly affects ride comfort. Theoretical calculations show that increasing the speed by 50 kilometers per hour typically results in a noise increase of 2 to 3 decibels for trains. But the CR450 high-speed train achieved a 2 decibel reduction in passenger cabin noise, and the overall noise level is comparable to that of the existing high-speed train running at a speed of 350 kilometers per hour. More comfortable. Carefully observing the CR450 high-speed train, in order to "slim down", its height has decreased from 4.05 meters to 3.85 meters, but when entering the interior of the carriage, the height of the passenger compartment remains unchanged. Through integrated and miniaturized design, the passenger usage area of CR450 high-speed trains has increased by 4%, and the storage area for large luggage has doubled. More diverse. The lighting can automatically adjust its brightness according to the outdoor environment; Contactless bathroom with "air button" function; We are committed to providing passengers with diversified, convenient, and personalized services to improve their riding experience, "said Ren Guangqiang, Deputy Director of the Technical Department of the Rolling Stock Department of China Railway Group, adding a variety of options such as family private rooms and multi-functional rooms. The development of the CR450 high-speed train, which is the first standard system for operating high-speed trains with a speed of 400 kilometers per hour, is a real exploration of "no man's land". ——This tests the ability of original innovation. What should the CR450 high-speed train be like? How should technical indicators be determined? What level should each key component reach? How to ensure safety? In 2018, China Railway Group launched research on the basic theory and key technologies of high-speed rail operating at a speed of 400 kilometers per hour; Officially started research and development in 2021; In 2022, the overall technical conditions will be released, and a large number of simulation calculations and ground bench tests will be carried out. Technical condition parameter tests will be conducted on the Zhengzhou Wanzhou and Jinan Zhengzhou high-speed railways, and new technology component replacement tests will be conducted on the Mimeng and Fuzhou Xiamen high-speed railways; In 2024, the production of prototype vehicles will officially begin... "During this process, we have established and improved a research and development mechanism that combines experimental exploration with iterative research and development," said Li Yongheng, Director of the Equipment Technology Department of the Science and Information Technology Department of China Railway Group. More than 200000 kilometers of line testing have accumulated a large amount of data, coupled with over a thousand simulation calculations and ground bench tests, jointly supporting the completion of the CR450 high-speed train design scheme. ——This tests the exploration of boundary limits. The CR450 high-speed train project is the first in the world to determine boundary conditions and verify top-level indicators through actual line tests, and to develop technical conditions for the project based on demand Introduction by Zhang Bo, Director of the Rolling Stock Institute of China Academy of Railway Sciences Group Corporation. The R&D team has completed more than 100 experiments to explore the changes in parameters related to train speed improvement, and obtained data characteristics under different speed conditions and different working conditions such as bridges, tunnels, and curves, laying a solid foundation for the development of CR450 high-speed trains. ——This tests the collaborative ability of multiple disciplines and fields. In the development process of CR450 high-speed trains, there are many constraints between technical indicators, such as running fast and being able to stop. Multiple technical indicators are constrained, and the determination of each detailed plan must be optimized. Taking weight loss as an example, if the speed is faster, the "muscles and bones" of the high-speed train must be stronger to ensure safety. But in order to reduce energy consumption and braking distance, high-speed trains must also try to slim down as much as possible? What should I do? Strengthening the load-bearing area; Non load bearing parts, weight loss. In order to reduce weight, all components, from cables to car bodies and bogies, need to be weighed and meet the standards before assembly, "said Tao Guidong, Deputy Chief Engineer of CRRC Sifang. The traction system reduces weight by 15% while ensuring power improvement; The braking system reduces weight by 10% while meeting higher braking requirements; The CR450 achieved an overall weight reduction of 10% and a weight loss of 50 tons by reducing the weight of the vehicle by 10%. For the first time, China has established a standard system for commercial operation of high-speed trains with a speed of 400 kilometers per hour globally through the development of CR450 high-speed train samples, including the use of bogie wrap structures, time sensitive nets, and permanent magnet traction motors. A high-speed train with over 40000 components that spans industry, academia, and research, deeply integrates and collaboratively innovates. The CR450 high-speed train is a comprehensive demonstration of China's technological innovation and high-end equipment manufacturing strength Li Yongheng said. This is the best manifestation of the strong advantages of the new national system. The R&D team of CR450 high-speed trains is an innovative consortium that spans industry, academia, and research. Under the leadership of China Railway Group, CRRC, CRSC and many other enterprises, research institutions such as the Academy of Railway Sciences and the Chinese Academy of Sciences, and universities such as Beijing Jiaotong University, Central South University, Tongji University, all institutions have deep integration and collaborative innovation. Taking the research and development of noise reduction as an example, Sui Fusheng, a researcher at the Institute of Acoustics, Chinese Academy of Sciences, analyzed that the noise includes both aerodynamic noise and wheel rail vibration noise, with a wide frequency range. The improvement of speed and lightweight design pose great challenges to noise control. Different types of noise require different solutions. CRRC Sifang United Shipbuilding Research Institute solves the problem of low-frequency vibration and noise; CRRC Changke, in collaboration with Southwest Jiaotong University, conducted more than 10 tests in the vehicle level acoustic laboratory... Finally, it took a year and a half to conduct noise tests on new materials and structures, testing over 300 noise reduction schemes. The R&D team reduced the noise inside the passenger compartment of the CR450 high-speed train by 2 decibels through a vehicle division, zoning, and frequency division noise reduction scheme. This is the best example of the complete supply advantage of the industrial system. There are over 100 major enterprises and 2100 participating enterprises involved in the design and production of high-speed train components, from research and development, manufacturing to operation and maintenance services. Just the traction system alone has nearly 40 supporting enterprises participating in research and development, involving enterprises in various links of the material, manufacturing, testing and other industrial chains, "said Feng Jianghua, Chief Scientist of CRRC China. Weight reduction has been achieved through the use of new materials such as carbon fiber composites and magnesium alloys; Noise reduction utilizes new materials and structures such as floor dampers, acoustic metamaterial resonance units, acoustic metamaterial sound-absorbing partitions, and high damping interior panels; The traction motor uses high-level domestically produced insulation materials... This is the best proof of the advantage of having a large number of high-quality workers and talents. During the research and development process, a large number of researchers are determined to innovate and overcome one difficulty after another. Reduce resistance throughout the body and tap deeper into potential. Where is the most effective way to reduce air resistance? Research and development personnel analyze the air resistance experienced by different parts of the vehicle through extensive simulations and experiments, and explore the theoretical limits of drag reduction for each part. In the end, we found that there is still great potential for reducing drag in the bogie area Zhu Yan, Deputy Chief Engineer of CRRC Changke, explained that the bogie is the leg of the high-speed train, responsible for tasks such as load bearing, traction, braking, and vibration reduction. How to reduce drag? Through countless day and night simulation experiments, the R&D personnel have gradually mastered the operating rules of the complex flow field in the bogie area and innovatively proposed the encapsulation structure. The wrapping structure is like putting 'pants' on the bogie, which requires consideration of both drag reduction effect and multiple goals such as heat dissipation, strength, and stiffness. Design is a great challenge, "said Professor Wang Wenjing from Beijing Jiaotong University. In the manufacturing process, great country craftsmen strive for excellence and build dreams with ingenuity. The CR450 prototype car body adopts a lighter and longer thin-walled aluminum alloy profile, which makes the body lighter and requires higher strength, posing great challenges to the welding manufacturing of the body Han Xiaohui, Chief Craftsman of CRRC Sifang, said that for this purpose, the production line has introduced laser arc composite welding technology for the first time, which has increased the connection strength of the vehicle body by 20% and the flatness by 3 to 5 times. The relevant person in charge of China Railway Group introduced that the next step will be to arrange a series of line tests and assessments for CR450 high-speed train samples, further testing various performance indicators, and striving to put them into commercial operation as soon as possible. (New Society)