Multidiscipline design optimization for large-scale complex nonlinear dynamic system based on weak coupling interfaces

Abstract

Abstract For hi-tech manufacturing industries, developing large-scale complex nonlinear dynamic system must be taken as one of basic works, formulating problems to be solved, steering system design to a more preferable direction, and making correct strategic decisions. By using effective tools of big data mining, Dynamic Design Methodology was proposed to establish technical platform of Multidiscipline Design Optimization such as High Speed Rolling Stock, including three key technologies: i) Analysis graph of full-vehicle stability properties and variation patterns, providing instructive guidance on optimal parameter configuration of self-adaptive improved design for higher speed bogies to reduce track force; ii) Improved transaction strategy of flexible body to MBS interface, making boundary loading treatments more subtle to implement weak coupling interface of aluminium alloy car body to equipment cabin under floor frame; iii) Seamless collaboration with weldline fatigue damage assessments, ensuring structure integrity via correct Modal Stress Recovery. Steel rail profession unilaterally initiated improved design of wheel-rail relationship, which is proved to be unfavourable to commercial applications for Chinese High Speed Rails. On first fluttering phenomenon of service car body, contrastive analyses of line tracking tests and rigid-flex coupling simulations show that internal lateral coupling resonance of such as traction converter has been one of main restrictive factors that determine cost effectiveness. Whilst self-adaptive improved solution is one of more favourable options. Comprehensive evaluations show that only under rational conditions of wheel-rail matching, i.e. 0.10 ≥ λeN > λemin and λemin= (0.03–0.06), can this low cast solution achieve three goals of low track conicity, optimal route planning and investment benefit maximization.