Calculation investigation of the strength of the composite wheel rim

The aim of the research is to reduce the unsprung mass, the moment of inertia of the racing automobile’s wheel while maintaining the necessary strength due to the using of composite materials in its construction. Currently, the composite materials have been obtained a widespread usage as structural materials in the automobile assemblies and units. Particularly, the using of modern composite materials in the transmission elements of the automobile, such as drive shafts, axle shafts or wheels, makes it possible to substantially improve the performances of the wheeled vehicle: reduce the full and the unsprung weight. It is possible to point out from the modern composite materials, the polymeric composite materials having carbon fibers as a reinforcing element, which are possessing a low density and the best combining a high level of specific strength with producibility of the products. The object of the research is the racing automobile’s wheel which belongs to the class of “Formula Student”. The usage of composite materials in the construction of similar wheels, as well as the estimated evaluation of the wheel’s strength during its manufacturing from composite materials are discussed. The regulations of the competitions permit a great freedom in choosing the wheel construction. The estimated strength evaluation was carried out by the finite element method, the original finite element wheel model was developed for this purpose taking into account the anisotropic properties of the reinforced materials. The computational investigation of the strength of the selected construction showed that the rim which is made of the composite material has an excessive safety factor at the design loads. The proposed constructive decision allows to reduce the wheel weight by 33% (up to 1.68 kg) in comparison with the one-piece wheel made of magnesium alloys (2.5 kg).

wheel, composite rim, composite wheel, carbon fiber, finite element method, sport car