For more than a century, pneumatic (air-inflated) tires have totally dominated the market for road vehicle tires. However, in the recent two decades, interest has grown in developing airless tires. Some of the authors were involved in design of an early version in composite material 15-30 years ago for passenger cars. Presently, the EU project LEON-T (Low particle Emissions and lOw Noise Tyres) includes a part in which prototypes for innovative heavy goods vehicle (HGV) tires are developed, with the main purpose to reduce noise emission by 6 dB. To reduce noise that much it is believed that airless tires are needed. A special challenge is to get a durable design able to carry typical truck tire loads.
This paper introduces the principal design of airless tires. Airless tire prototypes are intended to be developed by partner Euroturbine, in cooperation with mainly Applus+ IDIADA, VTI and subcontractor Lightness by Design. The tire consists of a rim, load-carrying spokes, composite belt, and rubber tread. The primary focus is on the modelling of static and dynamic behavior of the tire and the corresponding impact on the tire design.
By aid of FE modelling, the tire static behavior (radial, lateral, and longitudinal stiffness) is analyzed. It is found that the radial stiffness of the modelled tire is within the ranges of that of a conventional pneumatic tire, however, the longitudinal and lateral stiffnesses are 2.5 and 2 times higher, respectively. The same tire model is used to study its dynamic behavior (modal and noise characteristics) which are then compared with that from measurements. For modal studies, the point inertances are used as a reference for test and simulation validation. The same for the noise study is the noise transfer function that is measured at a predetermined location, using a microphone in the vicinity of the tire.