The University of Paderborn is researching optimized axles for less particulate matter.

Fine particulate emissions in the city are often associated with soot particles from vehicle exhausts. However, according to the German Federal Environmental Foundation (DBU), a much larger proportion of particulate emissions can be attributed to tire wear. According to the DBU, tire wear in road traffic is burdensome for humans and the environment and is responsible for about one-third of the total 330,000 tons of microplastics released annually in Germany. Additionally, tire wear is considered a significant factor in the introduction of microplastics into the world's oceans, according to a study by the International Union for Conservation of Nature (IUCN).

Researchers at the University of Paderborn conducted a project funded by the DBU with 125,000 euros and concluded that the design of the axle systems also plays a crucial role in tire wear.

"The amount of tire wear depends, among other things, on the interaction between the chassis, tires, and road, with the design of the axle systems having a relatively large influence," explains Prof. Dr. Walter Sextro, project manager and head of the Chair for Dynamics and Mechatronics at the University of Paderborn.

In the investigations, experimentally validated models of a tire and a rear axle of a mid-size production vehicle were used. By optimizing the axle system, they were able to reduce the amount of tire wear by about half under the chosen simulation conditions at a speed of 100 kilometers per hour, with comparatively minor geometric changes to the axle, Sextro said.

E-cars have even more wear due to the heavy battery weight

According to the project manager, real driving trials by a project partner had already shown the potential for reduction. As part of the project, a methodology was developed to calculate the friction work between the tire and road as an indicator of the amount of tire wear and to analyze the influence of axle properties on friction work.

There are plans to expand the simulation to include a model of the front axle and the vehicle structure. This would allow for a more detailed analysis of how axle properties influence tire wear, taking vehicle dynamics into account. These calculation results could then be transferred to real-world traffic on an even larger scale.

According to Sextro, in addition to the requirements for driving dynamics, comfort, and safety, reducing tire wear should also be considered when improving a chassis. "Reducing tire wear is generally not a primary criterion in chassis design," the researcher said. However, in the preliminary design of vehicles, a detailed simulation of tire wear should be considered.

"Because in electrically driven vehicles, the heavy batteries lead to even more tire wear," explains Sextro.