Research On Dynamic Performance Of Suspended Monorail Freight Vehicles

Multimodal transport is a transportation process that is completed by two kinds of vehicles or more which are connected with each other and transported together.It has the characteristics of efficient organization,low logistics cost and great benefit of freight transportation.In recent years,with the changes of social and economic development in China,multimodal transport has attracted increasing attention,and its development has ushered in an important opportunity period.The upgrading and development of multimodal transport in China will inevitably promote the innovation of technical equipment.As a new multimodal transport system,the suspended monorail freight system of standard container transport can solve the problems of poor connection and high cost in the process of multimodal transport.It can accelerate the interconnection of railway,highway and waterway,so as to achieve seamless connection,information sharing and create conditions for multimodal transport.The suspended monorail vehicle with symmetrical steel wheel/rail bogies is the first case in the world,and the dynamic performance of its vehicle system needs to be further studied.The thesis firstly introduces the main characteristics of suspended monorail system,and summarizes the development status and research progress of suspended monorail system at home and abroad.The technical parameters and bogie structural features of suspended monorail freight vehicles are introduced.The evaluation criteria for dynamic performance of railway vehicles at home and abroad are studied.The evaluation and test criteria for dynamic performance of suspended monorail freight vehicles are analyzed and summarized.According to the theoretical frame system of vehicle system dynamics,the evaluation criteria are divided into hunting motion stability,ride behaviour and curving safety.Based on the theory of vehicle system dynamics,the whole vehicle dynamic model of suspended monorail freight vehicle with 48 degrees of freedom is established and the vehicle dynamic performance indexes under different suspension parameters are simulated.The influence of suspension parameters on vehicle dynamic performance is analyzed comprehensively,and the suspension parameters are optimized.After optimization,all dynamic indexes of suspension monorail freight vehicles meet the evaluation criteria and have greater safety margin.In view of the feature of the monorail vehicle,the safety index of curve negotiation is analyzed at different speeds.The main speed limiting factors and theoretical maximum speed were found.A more reasonable speed limit proposal for the vehicle negotiating small radius curve was proposed.The thesis summarizes the evaluation methods and indexes of dynamic performance of suspended monorail freight cars,analyzes comprehensively the influence of main suspension parameters on vehicle dynamic performance and optimizes parameters,and puts forward a more reasonable speed limit proposal for small radius curve negotiation.The research results are of great significance to promote the development of new multimodal transport vehicles in China.