Rheology of an Inverted Cholesteric Droplet under Shear Flow

Fluids

Adriano Tiribocchi¹  Federico Fadda²  Giuseppe Gonnella³  Enzo Orlandini⁴  Antonio Lamura⁵ 

[1] Center for Life Nano Science, IIT, 00161 Roma, Italy;Department of Chemical Engineering, Kyoto University, Kyoto 615-8510, Japan;Department of Physics and Sezione INFN Bari, 70126 Bari, Italy;Departmento of Physics and Astronomy and Sezione INFN, Università di Padova, 35131 Padova, Italy;Istituto Applicazioni Calcolo, CNR, 70126 Bari, Italy;

关键词: cholesteric liquid crystals;    shear dynamics;    emulsions;   

DOI  :  10.3390/fluids3030047

来源: DOAJ

【 摘 要 】

The dynamics of a quasi two-dimensional isotropic droplet in a cholesteric liquid crystal medium under symmetric shear flow is studied by lattice Boltzmann simulations. We consider a geometry in which the flow direction is along the axis of the cholesteric, as this setup exhibits a significant viscoelastic response to external stress. We find that the dynamics depends on the magnitude of the shear rate, the anchoring strength of the liquid crystal at the droplet interface and the chirality. While low shear rate and weak interface anchoring the system shows a non-Newtonian behavior, a Newtonian-like response is observed at high shear rate and strong interface anchoring. This is investigated both by estimating the secondary flow profile, namely a flow emerging along the out-of-plane direction (absent in fully-Newtonian fluids, such as water) and by monitoring defect formation and dynamics, which significantly alter the rheological response of the system.

【 授权许可】

Unknown