Determination of the normal spring stiffness coefficient in the linear spring-dashpot contact model of discrete element method

Author(s)

Navarro, Helio A. ^[1] ; de Souza Braun, Meire P. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Engn Mecan, Escola Engn Sao Carlos, BR-13566590 Sao Paulo - Brazil

• Document type: Journal article
• Source: Powder Technology; v. 246, p. 707-722, SEP 2013.
• Web of Science Citations: 12

Abstract

The discrete element method is a method for simulation of a particle system. For the ``soft-sphere{''} mechanism of particle interactions, there are several models for normal contact forces, namely linear spring-dashpot, and non-linear damped Hertzian spring-dashpot, among others. The focus of this paper is to determine the normal spring stiffness coefficient of the linear model through the numerical solution for the overlap between particles in non-linear models. The linear spring stiffness is determined using equivalence between the linear and the nonlinear models. Using the MFIX computational code, the proposed approach is applied in the numerical simulations of two problems: single freely falling particle and bubbling fluidized bed. A method based on mean dimensionless overlap is suggested as an initial estimate to determine the normal spring stiffness coefficient. Other possible methods for computing the stiffness coefficient are also discussed in this work, e.g., maximum dimensionless overlap and dimensionless contact duration. (C) 2013 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 10/19769-4 - Study of the dynamic in gas-solid systems by numerical simulation using particle and finite volume approaches
• Grantee: Helio Aparecido Navarro
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/03468-0 - Study of the dynamic in granular systems by numerical simulation using particle and finite volume approaches
• Grantee: Helio Aparecido Navarro
• Support Opportunities: Scholarships abroad - Research