Fluid flow simulation on a Turritella-seashell-like geometry demonstrating its ability as static mixer for inline mixing

Abstract

Inspired by the turritella’s unique hydrodynamic behaviour of self-orientation parallel to the current and specialization in burrowing, here, we demonstrate that a turritella-seashell-like geometry can serve as an effective static mixer insert to induce inline mixing in a pipe. A method to mathematically parametrize a simplified turritella-seashell-like geometry is presented. Through CFD studies, a two-step mixing mechanism is proposed and its performance is investigated as a function of the inlet velocity, pipe diameter, surface boundary conditions and insert geometry parameters. The mixing output is nearly independent of the inlet velocity in the studied range. The no-slip boundary condition at the pipe wall is essential in creating shearing in the fluid, without which no mixing is observed. The insert geometry can be tuned to minimize the pressure drop by over 40% without significantly affecting the mixing output. The insights obtained herewith are discussed in interest of designing new static mixers.