Eur. Phys. J. E (2010) 32: 357-363
https://doi.org/10.1140/epje/i2010-10638-7

Regular Article

A direct numerical simulation method for complex modulus of particle dispersions

¹ Department of Chemical Engineering, Kyoto University, 615-8510, Kyoto, Japan
² CREST, Japan Science and Technology Agency, 332-0012, Kawaguchi, Japan

^* e-mail: tiwashit@utk.edu
^** e-mail: ryoichi@cheme.kyoto-u.ac.jp

Received: 31 August 2009
Accepted: 8 July 2010
Published online: 11 August 2010

Abstract

We report an extension of the smoothed profile method (SPM) (Y. Nakayama, K. Kim, and R. Yamamoto, Eur. Phys. J. E 26, 361 (2008)), a direct numerical simulation method for calculating the complex modulus of the dispersion of particles, in which we introduce a temporally oscillatory external force into the system. The validity of the method was examined by evaluating the storage G’() and loss G”() moduli of a system composed of identical spherical particles dispersed in an incompressible Newtonian host fluid at volume fractions of = 0 , 0.41, 0.46, and 0.51. The moduli were evaluated at several frequencies of shear flow; the shear flow used here has a zigzag profile, as is consistent with the usual periodic boundary conditions. The simulation results were compared with several experiments for colloidal dispersions of spherical particles.