In exploring hypersonic propulsion, precooler combined engines require the development of lightweight, efficient, and compact heat exchangers (HX). As additive manufacturing technology continues to progress, triply periodic minimal surface (TPMS) structures, characterized by exceptionally high surface area to volume ratios and intricate geometric structures, have demonstrated superior heat transfer performance. This research examines the thermal-hydraulic (TH) behavior of FKS and Diamond as heat transfer structures under different Reynolds numbers through numerical simulations. The Nusselt number for FKS is 13.2%–17.6% higher than Diamond, while the friction factor for FKS is approximately 18.8%–29.3% higher. A detailed analysis of the internal flow mechanisms reveals that the flow pattern within TPMS can be summarized as cyclic convergence-separation-convergence. The fluid experiences constant disturbances from the structure in all spatial directions, generating strong turbulent mixing and large wall shear stresses, which significantly enhance heat transfer performance.

Despite their outstanding thermal insulation and ultralight structure, silica aerogels suffer from inherent mechanical fragility, making the investigation of their mechanical behavior crucial for expanding their practical utility in advanced applications. To enhance their mechanical performance, this study introduces a dual-phase reinforcement strategy by anisotropically incorporating carbon nanotubes (CNTs) and graphene oxide (GO) sheets into the aerogel matrix. Using molecular dynamic simulations, we systematically investigate the tensile behavior and pore structure evolution of these hetero-structured composites. The results reveal a non-monotonic dependence of tensile strength on loading ratio, distinguishing three strain-dependent reinforcement regimes. High loading content (11.1%) significantly improves strength under low strain (0–26%), whereas low loading levels (1.8%) are more effective at preserving structural integrity under large strain (44–50%). Moderate loading (5.1%) yields balanced performance in intermediate regimes. While increasing carbon content reduces initial pore size by partially filling the framework, tensile deformation leads to interfacial debonding and the formation of larger pores due to CNT–GO hybrid structure interactions. This work elucidates a dual reinforcement mechanism—physical pore confinement and interfacial coupling—highlighting the critical role of nanostructure geometry in tuning strain-specific mechanical responses. The findings provide mechanistic insights into anisotropic nanocomposite behavior and offer guidance for designing robust porous materials for structural and functional applications.

The mechanical stability of carbon aerogels, particularly their thermal insulation performance, is closely linked to their elastic modulus. This property plays a crucial role in determining the material’s overall mechanical stability. The objective of this study is to enhance the accuracy of elastic modulus predictions for carbon aerogels using a power-scaling model. By setting the prefactor of the Gibson and Ashby equation to 1.0, accurate predictions of the elastic modulus can be achieved if the correct scaling exponent is determined. Twelve sets of experimental data were used to fit the power-scaling model, revealing that the scaling exponent for the elastic modulus of carbon aerogels typically falls between 2.2 and 3.0. This range is narrower than the 2.0 to 4.0 range reported in the literature, with a median value of 2.6 providing reliable predictions. Additionally, a relationship between the solid thermal conductivity and the elastic modulus of carbon aerogels was established using a thermal conduction model. The study also examined the elastic modulus of carbon nanotube and graphene aerogels—both allotropes of carbon aerogel. By fitting experimental data into the power-scaling model, the scaling exponents for carbon nanotube aerogels and graphene aerogels were found to range from 2.7 to 3.5 and 2.7 to 3.7, respectively. Median exponent values of 3.1 and 3.2 were identified as optimal for predicting the elastic moduli of carbon nanotube and graphene aerogels.

Windows are a major contributor to energy loss in buildings, particularly in hot climates where solar radiation heat gain significantly increases cooling demand. An ideal energy-efficient window must maintain high visible light transmittance while effectively blocking ultraviolet and near-infrared radiation, presenting a significant challenge for material design. We propose a plasma silica aerogel window utilizing the local surface plasmon resonance effect of plasmonic nanoparticles. This design incorporates indium tin oxide (ITO) nanospheres (for broad-band UV/NIR blocking) and silver (Ag) nanocylinders (targeted blocking of the 0.78–0.9 μm NIR band) co-doped into the silica aerogel. This design achieves a visible light transmittance of 0.8, a haze value below 0.12, and a photothermal ratio of 0.91. Building simulations indicate that compared to traditional glass, this window can achieve annual energy savings of 20–40% and significantly reduce the economic losses associated with traditional glass, providing a feasible solution for sustainable buildings.

Alumina aerogels are a class of nanoporous materials featuring tailorable three-dimensional pore architectures with porosities exceeding 90%, exhibiting promising prospects for energy-efficient thermal management applications. However, quantitative models linking pore structure to macroscopic thermo-mechanical performance remain scarce, hindering their rational design and performance optimization. The thermal conductivity of alumina aerogel was experimentally studied based on the steady-state heat conduction method, and the elastic modulus of the material was also measured based on the thermal mechanical coupling effect method. Combining with the literature data, the engineering calculation models were proposed to predict the thermal conductivity and elastic modulus as well as their upper and lower limits, which can help to provide guidance for the rational design of porous architectures. Furthermore, these models were extended to two representative porous composite materials, namely alumina–silica aerogels and fiber-reinforced alumina aerogels. The effective thermal conductivity and elastic modulus of the two composites were estimated by the Geometric Mean Model and the Gibson and Ashby scaling formula, respectively. Literature data were employed to validate the present predictions. The effect of the molar ratio of Al:Si on the thermal conductivity and elastic modulus of the alumina–silica aerogel was analyzed: the thermal conductivity can be reduced by about 13.1–25.5% as the Al:Si decreases from 8:1 to 2:1 for densities in the range of 50–250 kg/m³, while the reduction of the elastic modulus does not exceed 7% as the Al:Si decreases from 8:1 to 3:1. The effect of the glass fiber content on the fiber-reinforced alumina aerogel was also discussed: the elastic modulus can be reinforced by about 1.61–119.2% as the volume fraction of the glass fiber increases from 0.1 to 1.4% in the density range of 100–200 kg/m³, while the thermal conductivity is only increased by about 0.18–4.7%. These predictive tools provide a quantitative framework for achieving the optimization of structure–property relationships in advanced porous thermal insulation materials.