Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel Inclusions
Silica aerogel possesses a significantly lower thermal conductivity compared to still air at room temperature, thanks to its high porosity and advanced thermal and physical properties. It is extensively investigated for its potential use as an insulation material, usually being incorporated into oth...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-11-01
|
| Series: | Energies |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1073/17/23/5898 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1846124297649651712 |
|---|---|
| author | Eugene D. Skouras Georgia Tsolou Alexandros N. Kalarakis |
| author_facet | Eugene D. Skouras Georgia Tsolou Alexandros N. Kalarakis |
| author_sort | Eugene D. Skouras |
| collection | DOAJ |
| description | Silica aerogel possesses a significantly lower thermal conductivity compared to still air at room temperature, thanks to its high porosity and advanced thermal and physical properties. It is extensively investigated for its potential use as an insulation material, usually being incorporated into other matrix materials, such as cement plasters, to enhance the overall thermal performance with minimal weight load. The development of lightweight thermal insulation materials is a key step in reducing energy consumption in hot and cold environments during construction and in thermal equipment. The superior insulation capabilities of aerogels stem from their nanostructured SiO<sub>2</sub> framework, which induces nanoscale rarefaction effects on the enclosed air near the SiO<sub>2</sub> structure. This study reconstructed the nanostructured SiO<sub>2</sub> network of modern aerogels using microscopy imaging and the literature data and integrated it into sophisticated heat transfer simulations at a microscopic level to predict its thermal performance. The simulation assumed conduction as the primary energy dissipation mechanism, incorporating local rarefaction effects based on kinetic theory approaches. SiO<sub>2</sub> aggregates were modeled as interconnected strings of spherical beads, with variations in the aggregate size explored in a parametric study. Nanoscale rarefaction phenomena, such as slip wall and Knudsen diffusion, prevalent at these grain sizes and structures, were incorporated to refine the modeling approach. The degree of the aerogel content relative to the effective properties of the multiphasic material was then investigated systematically along the multilayered mortar thickness and on a representative multiphasic layer at the mesoscopic level. The results quantify the significant decrease in the thermal conductivity of the heterogeneous material as the porosity of the aerogel increased. The insulation performance of this aerogel incorporated into cement plasters was assessed with this hierarchical approach and validated against experimental data, providing insights for the optimization of the fabrication process and potential applications in construction. |
| format | Article |
| id | doaj-art-80b2eec8c8cc4d8ca7b36408f856fd91 |
| institution | Kabale University |
| issn | 1996-1073 |
| language | English |
| publishDate | 2024-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj-art-80b2eec8c8cc4d8ca7b36408f856fd912024-12-13T16:25:18ZengMDPI AGEnergies1996-10732024-11-011723589810.3390/en17235898Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel InclusionsEugene D. Skouras0Georgia Tsolou1Alexandros N. Kalarakis2Institute of Chemical Engineering Sciences, Foundation for Research and Technology-Hellas, GR-26504 Patras, GreeceLaboratory of Materials and Structures Analysis, Department of Mechanical Engineering, School of Engineering, University of the Peloponnese, GR-26334 Patras, GreeceLaboratory of Materials and Structures Analysis, Department of Mechanical Engineering, School of Engineering, University of the Peloponnese, GR-26334 Patras, GreeceSilica aerogel possesses a significantly lower thermal conductivity compared to still air at room temperature, thanks to its high porosity and advanced thermal and physical properties. It is extensively investigated for its potential use as an insulation material, usually being incorporated into other matrix materials, such as cement plasters, to enhance the overall thermal performance with minimal weight load. The development of lightweight thermal insulation materials is a key step in reducing energy consumption in hot and cold environments during construction and in thermal equipment. The superior insulation capabilities of aerogels stem from their nanostructured SiO<sub>2</sub> framework, which induces nanoscale rarefaction effects on the enclosed air near the SiO<sub>2</sub> structure. This study reconstructed the nanostructured SiO<sub>2</sub> network of modern aerogels using microscopy imaging and the literature data and integrated it into sophisticated heat transfer simulations at a microscopic level to predict its thermal performance. The simulation assumed conduction as the primary energy dissipation mechanism, incorporating local rarefaction effects based on kinetic theory approaches. SiO<sub>2</sub> aggregates were modeled as interconnected strings of spherical beads, with variations in the aggregate size explored in a parametric study. Nanoscale rarefaction phenomena, such as slip wall and Knudsen diffusion, prevalent at these grain sizes and structures, were incorporated to refine the modeling approach. The degree of the aerogel content relative to the effective properties of the multiphasic material was then investigated systematically along the multilayered mortar thickness and on a representative multiphasic layer at the mesoscopic level. The results quantify the significant decrease in the thermal conductivity of the heterogeneous material as the porosity of the aerogel increased. The insulation performance of this aerogel incorporated into cement plasters was assessed with this hierarchical approach and validated against experimental data, providing insights for the optimization of the fabrication process and potential applications in construction.https://www.mdpi.com/1996-1073/17/23/5898silica aerogelsthermal insulationheat-transfer modelingmicrostructure reconstruction |
| spellingShingle | Eugene D. Skouras Georgia Tsolou Alexandros N. Kalarakis Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel Inclusions Energies silica aerogels thermal insulation heat-transfer modeling microstructure reconstruction |
| title | Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel Inclusions |
| title_full | Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel Inclusions |
| title_fullStr | Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel Inclusions |
| title_full_unstemmed | Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel Inclusions |
| title_short | Hierarchical Modeling of the Thermal Insulation Performance of Novel Plasters with Aerogel Inclusions |
| title_sort | hierarchical modeling of the thermal insulation performance of novel plasters with aerogel inclusions |
| topic | silica aerogels thermal insulation heat-transfer modeling microstructure reconstruction |
| url | https://www.mdpi.com/1996-1073/17/23/5898 |
| work_keys_str_mv | AT eugenedskouras hierarchicalmodelingofthethermalinsulationperformanceofnovelplasterswithaerogelinclusions AT georgiatsolou hierarchicalmodelingofthethermalinsulationperformanceofnovelplasterswithaerogelinclusions AT alexandrosnkalarakis hierarchicalmodelingofthethermalinsulationperformanceofnovelplasterswithaerogelinclusions |