Peristalsis intensified shear-free mixing of high-viscosity fluids at low Reynolds numbers in a bionic reactor

• A Bionic Small Intestine Circular Flow Peristaltic Reactor was constructed. • Achieved shear-free mixing of high-viscosity fluids at low Reynolds numbers. • The inner wall structure with villi and folds enhances mixing in the reactor. • Critical parametric thresholds: Peristalsis amplitude ≥75%, Re > 10. • A minimum of 65% energy reduction relative to traditional mechanical mixing. . In industrial processes, mixing high-viscosity fluids at low Reynolds number remains a challenge for traditional mechanical stirring methods. This study introduces a novel bionic small intestine circular flow peristaltic reactor (BSCPR) inspired by the mammalian digestive system. Its mixing performance was investigated through experiments and numerical simulations. Results show that the BSCPR can achieve efficient shear-free mixing of high-viscosity fluids at low Reynolds numbers with much lower energy cost than mechanical stirring. The presence of villi and fold structures on the inner wall significantly enhances mixing. The peristalsis amplitude, velocity, and displacement all affect mixing. Both experimental and simulation results demonstrate that during the process of mixing high viscosity fluids, by tuning the peristalsis velocity or displacement to maintain the Reynolds number above 10 with a peristalsis amplitude of 75%, highly efficient mixing can still be attained. Overall, the BSCPR shows great potential in industries requiring shear-free mixing of high viscosity fluids. .