Experimental Measurement of On-Vehicle Rolling Tire Contact Patch Shear Energy Intensity at Various Slip Angles

Search for this publication on Google Scholar
Chandrashekar, N. (2017). Experimental Measurement of On-Vehicle Rolling Tire Contact Patch Shear Energy Intensity at Various Slip Angles. Unc Charlotte Electronic Theses And Dissertations.
Download PDF

Analytics

295 views ◎
253 downloads ⇓


Abstract

It has long been accepted that tire wear is directly related to the energy generated due to shear at the contact patch. Tire wear at any given point on the contact patch is proportional to the amount of shear energy intensity acting at that point. In this research, shear energy intensity as a product of sliding displacements and frictional force at a sufficient number of points is mapped across the tire contact patch.The phenomenon of Frustrated Total Internal Reflection (FTIR) [1] is used to measure the normal stress distribution across the contact patch. The normal stress is calculated based on the amount of light intensity acting at each pixel across the contact patch. The tread blocks on the tire are painted with white dots, and a similar method without the dimpled plastic of the FTIR is used to obtain the point by point tread block displacements. With the help of computer image processing, shear energy intensity as a function of frictional force and tread block displacements are mapped at multiple time stamps across the contact patch at various slip angles. Results show that the total shear energy acting across the contact patch increase with increasing slip angles. This demonstrates that the tire is going to wear more aggressively as the slip angle increases. The shear energy intensity mapped across the contact patch show that the tire is going to experience more irregular wear as the slip angle increases. From the results, it is seen that the shear energy intensity is more uniformly spread out at very low slip angles and at higher slip angles, the shear energy intensity is almost zero at the leading edge of the contact patch and maximum at the trailing edge of the contact patch. This corroborates the premise that highest shear is at the trailing edge of the contact patch.

Details
Author

Chandrashekar, Nagarjun

Title

Experimental Measurement of On-Vehicle Rolling Tire Contact Patch Shear Energy Intensity at Various Slip Angles

Physical Description

1 online resource (57 pages) : PDF

Date

2017

Degree Granting Institution

University of North Carolina at Charlotte

Abstract

It has long been accepted that tire wear is directly related to the energy generated due to shear at the contact patch. Tire wear at any given point on the contact patch is proportional to the amount of shear energy intensity acting at that point. In this research, shear energy intensity as a product of sliding displacements and frictional force at a sufficient number of points is mapped across the tire contact patch.The phenomenon of Frustrated Total Internal Reflection (FTIR) [1] is used to measure the normal stress distribution across the contact patch. The normal stress is calculated based on the amount of light intensity acting at each pixel across the contact patch. The tread blocks on the tire are painted with white dots, and a similar method without the dimpled plastic of the FTIR is used to obtain the point by point tread block displacements. With the help of computer image processing, shear energy intensity as a function of frictional force and tread block displacements are mapped at multiple time stamps across the contact patch at various slip angles. Results show that the total shear energy acting across the contact patch increase with increasing slip angles. This demonstrates that the tire is going to wear more aggressively as the slip angle increases. The shear energy intensity mapped across the contact patch show that the tire is going to experience more irregular wear as the slip angle increases. From the results, it is seen that the shear energy intensity is more uniformly spread out at very low slip angles and at higher slip angles, the shear energy intensity is almost zero at the leading edge of the contact patch and maximum at the trailing edge of the contact patch. This corroborates the premise that highest shear is at the trailing edge of the contact patch.

Genre

masters theses

Subjects--Topics

Automobiles--Design and construction

Degree

M.S.

Keywords

Shear Energy Intensity
Tire Footprint
Tire Wear

Subject Area

Mechanical Engineering

Advisor(s)

Tkacik, Peter

Committee Members

Keanini, Russell
Bari, Saiful

Degree Note

Thesis (M.S.)--University of North Carolina at Charlotte, 2017.

Rights Statement

This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). For additional information, see http://rightsstatements.org/page/InC/1.0/.

Rights Holder Information

Copyright is held by the author unless otherwise indicated.

Identifier

Chandrashekar_uncc_0694N_11501

Permalink

http://hdl.handle.net/20.500.13093/etd:102