Thermomechanical Analysis of a Bio‐Inspired Lightweight Multifunctional Structure

Abstract

Cuttlebone constitutes the inner shell of a cuttlefish, and it has a highly porous chambered microstructure of about 93% porosity by volume. [1] Cuttlebone functions as a skeletal element and a rigid buoyancy tank, which allows the organism to control its overall density by regulating the gas/liquid ratio inside its porous structure. [2] As some cuttlefish can live up to 600 m deep in the ocean, the partially gas-filled cuttlebone is required to withstand extreme compressive loading from the water pressure (up to 60 atm). [3,4] Previous studies have suggested that cuttlebone's remarkable damage tolerance and high stiffness can be attributed to its characteristic "wall-septa" internal morphology. [5] Several previous studies on cuttlebone have explored its potential applications by exploiting its chemical, structural, and mechanical characteristics as a natural cellular material. For example, cuttlebone itself can be used as a filler in natural rubber [6] and acrylic bone cement, [7] the mechanical properties of which are comparable to commercial products. In addition, a poly coated hydroxyapatite scaffold derived from cuttlebone through a hydrothermal transformation process was shown to exhibit enhanced mechanical properties and is a good candidate for bone tissue engineering applications. [8-10] Previous research on bio-inspired structures based on cuttlebone has generally focused on structural applications, motivated by cuttlebone's low density and high strength. [1,4,11,12] Currently, little research has been carried out to explore the potential multifunctional performance of cuttleboneinspired structures. In particular, the "wall-septa" morphology of cuttlebone resembles the arrangement of a plate and pins in a typical pin-fin heat sink [13,14] as well as the sandwich structure used in an integrated thermal protection system (ITPS) for spacecraft vehicles. [15-17] The combination of high mechanical performance (stiffness and damage tolerance), low density, and pin-fin-like configuration motivates us to explore the potential thermomechanical applications of cuttlebone-inspired structures. In addition to computationally analyzing the mechanical performance of the cuttlebone structure based on high-resolution 3D structural reconstruction, this research systematically analyzes the feasibility of using cuttlebone as an inspiration for the design of novel lightweight multifunctional structures for thermal management applications, including an air-cooled heat sink for electronic devices and an ITPS for spacecraft vehicles. Regarding the air-cooled heat sink evaluation, devising effective thermal management methods for electronic components are becoming increasingly difficult due to the demand for higher performance and the continual miniaturization of electronic devices. Numerous studies have been conducted to analyze heat sinks with natural convection, including the effect of pin fin orientation and pressure drop on local heat transfer, [18-22] effective fin shape and height for maximum heat transfer, [23-25] and e...

Advanced Design and Manufacturing Approaches for Structures with Enhanced Thermal Management Performance: A Review

“…Inspired by the trunk of the Norway spruce, Lin et al [40] crafted gradient hollow ITP structures that achieved a notable surface temperature reduction of almost 40°C through finite element analysis (Figure 3b). Kanimba et al, [41] drawing from the cuttlefish bone structure, designed an air-cooled radiator mirroring this natural form, enhancing heat dissipation through increased air contact (Figure 3c). Fan et al, [42] utilizing butterfly wings as [39] Copyright 2023, Elsevier.…”

“…Reproduced with permission. [41] Copyright 2020, Wiley-VCH. d) Internal bionic butterfly wing heat transfer network.…”

“…c) An integrated thermal protection system (ITPS) and an aircooled heat sink for electronic devices inspired by the porous internal skeleton of cuttlefish. Reproduced with permission [41]. Copyright 2020, Wiley-VCH.…”