OPTIMAL DESIGN METHOD AND ITS APPLICATION ON THE ALUMINUM ALLOY HOLLOW EXTRUDED CROSS SECTION OF HIGH-SPEED CAR BODY

摘要

The geometric parameters of high-speed carbody underframe's cross section are analyzed to the mathematical model of cross section's inertia moment which can characterize the underframe's stiffness. To improve the bending resistance ability, the underframe's cross section is optimized by shape on the premise of no weight increase and no strength weakening. Through changing the cross section's thickness of up and low covers, thickness, position and angle of every ribbed slab, optimization calculation of cross section's inertia moment is carried out by genetic algorithm. The more reasonable cross section type is obtained. And through researching on the way and degree of effect on the above optimization variables, referenced rules of designing carbody underframe's aluminum alloy hollow extruded cross section are inducted.