Modeling of the oscillatory motion of vehicle suspension elements during the loading of a trailer with bulk material

The paper presents a study of the oscillatory dynamics of a road train when loading a semi-trailer with bulk material (grain), in particular, during reloading from a combine harvester hopper. It is established that the peculiarities of the location of the flow of bulk material significantly affect the vertical oscillations of the suspension elements of the vehicle and trailer, which in turn affects the technical condition of the vehicle and driver comfort. Analytical and numerical modelling of the dynamic behaviour of a road train is carried out, taking into account the design characteristics of the suspension, tyres, damping elements, as well as the conditions of load transfer from the bulk medium. Three main load points were evaluated: over the trailer axle, over the vehicle axle, and between the axles. The smallest fluctuations, with a reduction of up to 45% compared to the other positions, are observed when loading between the bridges. The mathematical model takes into account the complex disturbing effects arising from impulse loading and allows determining the modes of impact: rectangular (up to 60 l/min), cosine (up to 100 l/min) and exponential (over 100 l/min). The results obtained can be used to optimise the design of suspensions, plan routes and develop recommendations for safe loading. The distribution of masses in real operating conditions was also taken into account, which ensures the practical significance of the work for the agro-transport industry.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).