A numerical investigation of Newtonian and non-Newtonian fluid-filled nested hyperelastic structures under low-velocity impact loading

In body protection applications under impact loadings, the aim is to dissipate the striker’s energy through energy conversion mechanisms; therefore, utilizing applicable materials is one of the primary steps. A useful approach to absorbing the kinetic energy is employing fluids that offer the potential for viscous dissipation. This paper studied a class of smart materials known as shear thickening fluids (STFs) with a variable shear strain rate-dependent viscosity. Since the instability and fluidity of STFs probably influence their proper usage, an appropriate medium is required to keep and seal them. A hyperelastic material with high flexibility and low density is utilized as a nested medium for three fluid types: high viscous, low viscous, and STF. Subsequently, a low-velocity impact test was simulated using FEM, which is based on the coupled Eulerian-Lagrangian approach. Compared to the unfilled structure, numerical results show that the peak value of contact force between the striker and the sample in structures (filled with low-viscosity Newtonian fluid, high-viscosity Newtonian fluid, and non-Newtonian shear thickening fluid) reduced by ۳۸%, ۶۴%, and ۷۴%, respectively, indicating a considerable increase in impact energy absorption and STF superiority over other two Newtonian fluids.

کلیدواژه ها:

Shear thickening fluids (STFs) ، Low-velocity impact ، Coupled Eulerian-Lagrangian (CEL) ، Fluid-solid interaction (FSI)