SUBJECT: Ph.D. Proposal Presentation
   
BY: Yingdan Wu
   
TIME: Thursday, March 14, 2019, 1:15 p.m.
   
PLACE: MRDC Building, 3515
   
TITLE: SCHALLAMACH WAVES AND FRICTION-INDUCED SELF-OSCILLATIONS IN A PROTOTYPICAL BELT DRIVE SYSTEM
   
COMMITTEE: Dr. Michael Varenberg, Co-Chair (ME)
Dr. Michael J. Leamy, Co-Chair (ME)
Dr. Itzhak Green (ME)
Dr. Aldo A. Ferri (ME)
Dr. Matthew Brake (ME (Rice University))
 

SUMMARY

The high adhesive friction between an elastomer and its counterpart generally impedes sliding in the accepted sense. Instead, the displacement is accommodated by Schallamach waves of detachment, which are surface wrinkles that move across the contact zone. However, this has received little research attention in belt drive systems; sliding-based friction models are employed for nearly all belt drive mechanics studies. In light of this discrepancy, the rolling contact mechanics in a simple flat belt drive will be explored by considering Schallamach waves of detachment with regard to the following specific aspects. 1) A thorough understanding of the mechanism of detachment events and friction generated at the belt-pulley interface will be developed. 2) The characteristics of Schallamach waves-induced instabilities, including the contact and system’s instabilities, will be studied, focusing on their dependence on driving speed, loading conditions and the system’s inertia. Also, it is of interest to examine these waves and the global system instabilities in a fully-coupled manner such that 3) downstream effects of detachment events couple to the dynamic response of the belt drive system, and 4) the system’s dynamics couples to the generation of Schallamach waves. Further, the research intends 5) to propose a rolling friction model for elastomers, capable of computing mechanical energy losses involved with the contact instabilities. 6) A novel surface design will be examined to check the ability to influence, control and tailor the presence of friction-induced instabilities in belt drives. This research will also be beneficial to the analysis of other cases of rolling in elastomeric components, such as tires.