29th Annual Business Meeting and Conference on Tire Science and Technology

Doubletree Hotel Akron/Fairlawn: Akron, OH, USA

Monday, September 20, 2010: 3:00 PM
Aspen Ballroom (Doubletree Hotel Akron/Fairlawn)
Shashank Bezgam1, Lonny Thompson, PhD1, John Ziegert, PhD1, Timothy Rhyne, PhD2 and Steven Cron, PhD2, (1)Mechanical Engineering, Clemson University, Clemson, SC, (2)Michelin Americas Research Company, Greenville, SC
Recently, Michelin has invented an innovative non-pneumatic tire which has potential for improved handling, grip, comfort, and less rolling resistance when compared to a traditional pneumatic tire.  During high speed rolling in initial testing, the original prototype showed high noise levels at frequencies above 100 Hz. Previous work studied the effect of geometric parameters on spoke vibration and ground force interaction during high-speed rolling. In the present work, a 2D planar finite element model is used to simulate rolling of the non-pneumatic tire.  The current work considers the design and analysis of new alternate spoke pair concepts wherein from pair to pair the spoke properties are different, with every other spoke pair having the same properties.  Alternating spoke pair properties of thickness, curvature, or combinations of both are considered. The results indicate that for equivalent mass, the alternating spoke pair design with small changes, i.e. plus/minus 5% in spoke thickness between pairs broadens the range and increases the number of frequencies of peak amplitudes for the ground reaction force while reducing the magnitude of these peak amplitudes.  However, the model with alternating spoke pair thickness showed the same spoke vibration frequencies and amplitudes compared to a reference model with uniform spoke pairs with the same thickness distribution. In contrast, when small changes in curvature instead of thickness were introduced in the alternating spoke pairs design concept, the spoke vibration amplitudes reduced without much effect on the ground vibration. Combining thin spokes with large curvature within a pair and thick spokes with small curvature within the other spoke pair produces an effective design which reduces the amount of vibration in both the spoke and ground interaction.