Structural Optimum Design of a Railcar Coupler Energy Absorbing Device

Abstract

Abstract. In this paper, we carried out a structural optimization of an railcar coupler energy absorbing device. we established a finite element (FE) model and validated it by experimental results. We used a central composite design (CCD) and Hammersley design of experiments (DOE) to take samples for the variables. Based on these samples, we built an approximation model with the moving least squares method (MLAM). The maximum error percentage of the model was 2.30%. The main effect analysis indicated that the thickness T had the more significant effect on the average mean force (Favg) and the specific energy absorption (SEA). Considering the average mean force, fracture and buckling of the structure as constraints, we carried out parameter optimization using the global response surface method (GRSM) to gain a higher SEA. Finally, we obtained the optimum parameters (T = 7.72 mm, ɑ = 29.34º) with the SEA value of 35.28 kJ/kg. The value of SEA increased by 56.18%.