This paper aims to explain how digital light projection (DLP) additive manufacturing was used to print original fractal structuring manifolds (FSMs) with millimeter-scale channels to impart complex structures to flowing fluid streams. In this work, the term FSM refers to a single, printed structure composed of internal flow channels that merge and split in several locations. Creating FSMs with additive manufacturing increases the possible internal flow geometries that can be fabricated and tested compared to previous manufacturing techniques.
FSMs with original internal flow geometries were designed, printed and tested using computer-aided design (CAD) software, a DLP 3D printer and multiple fluid streams that include glycerol and photopolymer resin. Additionally, original devices were designed and fabricated to allow for viewing of the fluid structures produced by the FSMs. Bright-field microscopy was used to image fluid structures produced from experiments.
FSMs with complex internal channel geometries were produced and tested to demonstrate the ability to double or halve fluid layers via Baker’s transformations. The novel channel geometries created were obtainable with the unique advantages of additive manufacturing and led to composite streams with higher-order structure. Results were compared to FSMs fabricated with traditional manufacturing techniques.
This work establishes the feasibility of using additive manufacturing to produce FSMs, and it highlights the untapped potential in using additive manufacturing to fabricate advanced FSMs not previously described in literature. New fractal structures in composite flows may be accessible with the use of additive manufacturing for FSM fabrication. FSM designs can be rapidly iterated, and the influence of channel shape on fluid structure can be explored.
