Thermomechanical Analysis of a Bio-Inspired Lightweight Multifunctional Structure

This work investigates the thermal and mechanical performance of a bio-inspired lightweight structure, which is inspired by the porous (up to 93% porosity) internal skeleton of cuttlefish, also known as cuttlebone. The potential of using this structure as an air-cooled heat sink for electronic devices and an integrated thermal protection system (ITPS) is tested and systematically compared with three conventional structures based on wavy, pyramid, and cylindrical pin fin geometries. When cooling a hot spot (100 x 100 x 2 mm(3)) subjected to heat flow (250 W), and given the same solid volume fraction, the wavy and cuttlebone structures reduce the maximum temperature to 57 degrees C, which is 13 and 19 degrees C lower than for the pin fins and pyramid structures, respectively. Concerning the ITPS application, the cuttlebone exhibits the most isometric deformation with a 0.062 mm maximum standard deviation among its four corners. Moreover, the cuttlebone outperforms the other structures in terms of compressive strength (20%, 17%, and 219% increase compared with the wavy, pyramid, and pin fin structures, respectively). More importantly, the simulations indicate that the cuttlebone structure undergoes a graceful failure process due to the sequential buckling of the vertical walls compared with other structures.