COMPUTATIONAL AND EXPERIMENTAL STUDY OF THE STRENGTH OF AUTOMOBILE WHEELS UNDER IMPACT LOADS

Abstract

Modern automotive engineering is characterized by increasingly stringent requirements for safety, reliability, and durability of vehicle chassis components. One of the most critical structural elements of a vehicle is the wheel, which is subjected during operation not only to static loads but also to significant dynamic and impact loads caused by collisions with obstacles. The widespread use of cast aluminum wheels has intensified the need for reliable methods to assess their strength under certification impact test conditions. Despite the existence of regulatory standards, numerical modeling of the stress–strain state of wheels under impact loading remains insufficiently developed. The aim of this study is to develop and verify a computational–experimental methodology for evaluating the stress–strain state of cast aluminum automotive wheels subjected to impact loads simulating certification test conditions. To achieve this goal, an analysis of relevant standards was conducted, a finite element model of a virtual impact test bench was developed, nonlinear dynamic simulations of impact loading were performed, and the numerical results were compared with experimental strain gauge measurements. An additional objective was to assess the applicability of the dynamic coefficient commonly used in engineering practice. As a result of the study, spatial and temporal distributions of stresses and strains in the wheel structure under an oblique impact at an angle of 30° were obtained. It was found that the regions of maximum deformation predicted by the numerical model coincide with the zones of residual plastic deformation observed during post-test inspections. Comparison between numerical and experimental results demonstrated that the discrepancy in strain values at control points does not exceed 10–11 %, which is within acceptable engineering accuracy limits. Good agreement was also achieved for the main parameters of the oscillatory process, including the period, frequency, and logarithmic decrement of damping. In conclusion, the proposed computational–experimental methodology provides a reliable assessment of automotive wheel strength under impact loading and can be effectively applied during the design stage and preparation for certification tests. The use of a dynamic coefficient is acceptable for preliminary evaluations; however, direct numerical simulation of the impact process is recommended for final strength assessment.