A Bionic Peristaltic Process for Enhanced Powder Dispersion in Energetic High-Solid-Loading Slurries

This study introduces a paddle-less bionic peristaltic mixing process, inspired by intestinal biomechanics, for enhanced powder dispersion in energetic high-solid-loading slurries (80% solids). Periodic elastic conduit compression induces low-shear vortices, substantially reducing energy consumption compared with conventional mechanical stirring in solid propellant preparation. ANSYS Fluent simulations employing dynamic meshing and the Navier-Stokes equations demonstrate bidirectional flows and effective phase homogenization, achieving high-density uniformity after 300 s. Experiments using a NaCl/Al/HTPB solid-propellant simulant identified the optimal operating parameters as an extrusion duration of 3 s, an air pressure of 0.6 MPa, four peristaltic segments, and an intersegment spacing of 5 mm. Under these conditions, the mean density across the five axial sections was 1.513 g·cm^-3, and the axial-density standard deviation was 0.016 g·cm^-3, corresponding to an approximately 58% improvement in spatial uniformity relative to the baseline condition. Scanning electron microscopy confirms uniform particle coating and grading. This low-shear, energy-efficient method provides an innovative approach for solid propellant mixing and holds broad potential for other high-solid powder composites in pharmaceuticals and ceramics.