EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Towards the development and validation of new sets of functional thermoplastic composites, BioG3D has developed an open-materials prototype 3D printer for composite production with tailored fiber placement, enabled by Continuous Fiber Fabrication (CFF). Redesign and prototyping steps were carried out, implementing the function of coaxial extrusion of polymer filament along twisted Carbon Fiber (CF) multifilaments through a modified print head. Utilizing this customized setup, a number of parametric tools have been employed for the development of custom tool path generating algorithms, addressing the challenges posed by this novel printing approach, which calls for solutions beyond the capabilities of traditional planar slicing. Testing coupons with fiber patterns of different orientations and densities were investigated, in order to achieve programmable deformability upon thermal stimulus, by controlling the CF fiber trajectories. This investigation resulted in the fabrication and assembly of an axial flow cooling fan prototype, with composite blades as a proof-of-concept of the application of pre-programmed architectures in thermal management systems under different operating conditions. Computational Fluid Dynamics (CFD) simulations have been employed for the assessment of the shape transformation effect on air volume flow in 50-80°C operational temperature range. Based on simulation results, in lower temperature range, the deformed geometry of the blades presented up to 13.27% increase in air volume flow compared to the original, undeformed geometry, whereas in higher temperature range, the recovery of original shape results in a desirable decrease of volume flow loss from 18.24% to 11.89%, in comparison with the deformed state. The proposed approach paves the way for the development of smart composite components with enhanced cooling efficiency enabled by dynamically reconfigurable and reversible shape transformations.