Three triangular friction block configurations are commonly employed in high-speed train brake systems,namely,unperforated,perforated configuration with one circular hole,and perforated with three circular holes.In th...Three triangular friction block configurations are commonly employed in high-speed train brake systems,namely,unperforated,perforated configuration with one circular hole,and perforated with three circular holes.In this study,we adopted these friction block types to investigate the effect of perforated friction block configurations on the brake performance of high-speed trains based on a self-developed brake test rig.The results indicate the significant impact of the number of the holes on the wear behavior,temperature distribution,and vibration characteristics of the brake interface.The friction surface of the unperforated block is covered by wear debris,while the perforated blocks produce less wear debris.Furthermore,the one-hole block exhibits a more uniform temperature distribution and better vibration behavior than that with three holes.The friction brake is a dynamic process,during which separation and attachment between the pad and disc alternatively occur,and the perforated structure on the friction block can both trap and expel the wear debris.展开更多
The development direction of railways is toward the improvement of capacity and service quality, where the service quality includes safety, schedule, high speed, and comfort. In light of the existing cellular automato...The development direction of railways is toward the improvement of capacity and service quality, where the service quality includes safety, schedule, high speed, and comfort. In light of the existing cellular automaton models, in this paper, we develop a model to analyze the mixed running processes of trains with maximal speeds of 500 km/h and 350 km/h respectively in the moving block system. In the proposed model, we establish some sound rules to control the running processes of a train, where the rules include the departure rules in the intermediate stations, the overtaking rules, and the conditions of speed limitation for a train stopping at a station or passing through a station. With the consideration of the mixed ratio and the distance between two adjacent stations, the properties of the train traffic flow （including capacity and average speed） are simulated. The numerical results show that the interactions among different trains will affect the capacity, and a proper increase of the spatial distance between two adjacent stations can enhance the capacity and the average speed under the moving block.展开更多
With rapid development of the railway traffic, the moving block signaling system （MBS） method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway ...With rapid development of the railway traffic, the moving block signaling system （MBS） method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway while maintaining the required safety margins. In this framework, the tracking target point of the following train is moving forward with its leading train. This paper focuses on the energy saving tracking control of two successive trains in MBS. Nonlinear programming method is used to optimize the energy-saving speed trajectory of the following train. The real-time location of the leading train could be integrated into the optimization process. Due to simplicity, it can be used for online implementation. The feasibility and effectiveness are verified through simulation. The results show that the new method is efficient on energy saving even when disturbances present.展开更多
基金the financial support of the National Natural Science Foundation of China(Nos.U22A20181 and 52305187)the Fundamental Research Funds for the Central Universities(2682024CG008).
文摘Three triangular friction block configurations are commonly employed in high-speed train brake systems,namely,unperforated,perforated configuration with one circular hole,and perforated with three circular holes.In this study,we adopted these friction block types to investigate the effect of perforated friction block configurations on the brake performance of high-speed trains based on a self-developed brake test rig.The results indicate the significant impact of the number of the holes on the wear behavior,temperature distribution,and vibration characteristics of the brake interface.The friction surface of the unperforated block is covered by wear debris,while the perforated blocks produce less wear debris.Furthermore,the one-hole block exhibits a more uniform temperature distribution and better vibration behavior than that with three holes.The friction brake is a dynamic process,during which separation and attachment between the pad and disc alternatively occur,and the perforated structure on the friction block can both trap and expel the wear debris.
基金Project supported by the State Social Science Fund Project, China (Grant No. 11CJY067)the Natural Science Foundation of Gansu Province, China (Grant No. 1107RJYA070)
文摘The development direction of railways is toward the improvement of capacity and service quality, where the service quality includes safety, schedule, high speed, and comfort. In light of the existing cellular automaton models, in this paper, we develop a model to analyze the mixed running processes of trains with maximal speeds of 500 km/h and 350 km/h respectively in the moving block system. In the proposed model, we establish some sound rules to control the running processes of a train, where the rules include the departure rules in the intermediate stations, the overtaking rules, and the conditions of speed limitation for a train stopping at a station or passing through a station. With the consideration of the mixed ratio and the distance between two adjacent stations, the properties of the train traffic flow （including capacity and average speed） are simulated. The numerical results show that the interactions among different trains will affect the capacity, and a proper increase of the spatial distance between two adjacent stations can enhance the capacity and the average speed under the moving block.
文摘With rapid development of the railway traffic, the moving block signaling system （MBS） method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway while maintaining the required safety margins. In this framework, the tracking target point of the following train is moving forward with its leading train. This paper focuses on the energy saving tracking control of two successive trains in MBS. Nonlinear programming method is used to optimize the energy-saving speed trajectory of the following train. The real-time location of the leading train could be integrated into the optimization process. Due to simplicity, it can be used for online implementation. The feasibility and effectiveness are verified through simulation. The results show that the new method is efficient on energy saving even when disturbances present.
