Effective Thermal Conductivity Modelling for Closed-Cell Porous Media with Analytical Shape Factors

Bioinspired engineering of honeycomb structure – Using nature to inspire human innovation

“…For axial effective thermal conductivity c k always equal to 1 regardless of the cell shape, whereas c k is strongly related to cell shape in the lateral direction. Recently, Yang et al [165] proposed a fully analytical model for effective thermal conductivity of honeycombs, achieving the good prediction for honeycombs with various pore shapes for the full porosity range. They incorporated an analytical expression for shape factor based on the circularity which corrects the deviation caused from the non-circular (or non-spherical) pore inclusion into the Laplace heat conduction equation.…”

Thin-Shell Model for Effective Thermal and Electrical Conductivity of Highly Porous Closed-Cell Metal Foams

“…The so-called homogenization schemes relate the conductivity of the metal foam, e.g., the effective electrical conductivity σ eff , to the conductivity and volume fraction of the solid material phase, taking into account morphology, i.e., σ eff = σ eff (σ s , f s = 1 − φ, morphology). A review of homogenization schemes applicable to metal foams can be found in, e.g., Ranut (2015) for open-cell foam and Yang et al (2013a), Cuevas et al (2009 for closed-cell foams. As the underlying field equations for electrostatics and steady-state heat conduction are similar (see Table 1), the outcome of homogenization schemes derived for either one of the problems may be applied to the other one.…”

Thermo-fluidic characteristics of natural convection in honeycombs: The role of chimney enhancement

“…Honeycombs are naturally existing, bio-inspired structures with multiple channels with the advantage of ultra light-weight, high specific stiffness and strength as well as high specific surface area and high conductive walls, which are particularly attractive for heat dissipation. The previous investigations mainly focused on heat conduction [14][15][16], forced convection [17][18][19] and phase change [20][21][22] in various applications [23]. Yang et al [24] experimentally investigated the heat transfer enhancement by adding an adiabatic square chimney on the heated hexagonal honeycomb.…”