Modeling and Analysis of Non-Pneumatic Tyre by Using Ansys

Abstract

Non-pneumatic tires (NPT) or Tweels are the new developments at present increased attention because of potential advantages over pneumatic tires as these are having  low mass, no run flat, good contact pressure distribution, and low rolling resistance (RR).

In the pres work focuses on modeling and design with reference to vertical stiffness properties, contact pressure and energy loss due to rolling. The finite element analysis using Ansys software is used to study parametrically the vertical stiffness effect and the contact pressure influence with the rolling resistance response by considering the three design variables such as 1. Spokes thickness,  2. Thickness of shear band and  3. Shear modulus.

It is observed that the first two are geometric dependent and where as the third the material dependent parameter. The contact pressure will have more response or effect on the tyre analysis. During the analysis it is assumed to consider the static contact pressure of a non pneumatic tyre spokes as a function of vertical loads which are applied at the centre of hub. The shear band is as a rolling resistance from the shear friction of elastomers.

The design is modeled with CATIA. Where the hub of the Non-pneumatic tire is made with the Aluminium Alloy (Al:7075-T6) and the spokes and shear band with the PU and inner reinforcement and the outer reinforcement are made with the high strength steel (AISI-4340) and the thread is made up of rubber. The design is modeled for 3D lattice honeycomb spoke and the linear spokes.

The models were imported to ANSYS work bench to evaluate the results of deflection of the Non-pneumatic tire, von misses stress of the Non-pneumatic tire and the contact pressure of the Non-pneumatic tire with the road. The load at the hub centre were 3500N and 4000N respectively.

  Results indicate that all the design variables have significant effect on RR, with the shear band thickness and shear modulus having the greater effect. The Non-pneumatic tire is modeled in CATIA and analysis is validated through ANSYS.