(338l) Characterization of Flow of Non-Newtonian Fluid in Narrow Channels

A relative study has been done to compare Non-Newtonian fluid flow for shear rate dependent viscosity and forcing term approach for non-Newtonian effect. These models include the use of shear rate relation with viscosity and force term for non-Newtonian effects which can be combined with the lattice Boltzmann equation. This study has helped us to understand the difference of these two effects and advantage of using one method over another. This work mainly focuses on the shear thickening effect because we are keen to understand the hardening effect of shear thickening fluid (STF) at high shear rate which has been utilized in the body armor applications. This work aims at mesoscale simulations using lattice Boltzmann method to study the flow characteristics of the STF in narrow channels. Power law model has been used to define the non-Newtonian behavior of the fluid which relates the viscosity to the strain rate. In one method the relaxation time captures the effect of non-Newtonian behavior and in the other method external force captures the effect of non-Newtonian behavior. Maxima of 0.9 and minima of 0.58 of relaxation time has been observed for power law index of 1.6. The accuracy of the method has been checked by comparing the results with analytical solution.

Our work is related to studying the flow behaviour of non newtonian fluids using Lattice botlzmann method. It has been observed that the concentration of particle around 40% gives the shear thickening effect which is the main focus of my study where interaction between fluid and particle has to be observed which leads to the desired fluid behaviour.