Improving the thermal performance of building envelopes while reducing construction costs is a key challenge in sustainable building design. Phase change materials (PCMs) offer an effective solution for thermal energy storage due to their ability to absorb and release latent heat during phase transitions. This study proposes an innovative wall configuration incorporating a bio-sandwich panel composed of oriented strand board (OSB) and a bio-based PCM in order to enhance indoor thermal comfort while maintaining a reduced wall thickness.
A multilayer wall model was analyzed consisting of 1.5 cm of cement, 15 cm of brick, and 1.5 cm of plaster, resulting in a reference wall thickness of 18 cm without PCM. A second configuration integrates a 5 cm bio-sandwich panel made of two OSB layers (1 cm each) and a 3 cm layer of bio-based PCM. Heat transfer was simulated under summer climatic conditions representative of Constantine (36.3650° N, 5.5228° E), including solar radiation, wind speed, and ambient temperature variations. The PCM layer was positioned near the exterior surface to enhance thermal energy storage and release. Numerical simulations were conducted using experimentally derived correlations for equivalent heat capacity and thermal conductivity.
The results demonstrate that the wall containing the bio-sandwich panel significantly stabilizes indoor surface temperatures. During summer conditions, the interior wall temperature of the reference wall varied between 24.2 °C and 33.9 °C, whereas the proposed wall maintained temperatures between 26 °C and 28 °C. The maximum temperature amplitude was reduced from 7.35 °C to 1.75 °C, indicating a strong improvement in thermal stability and indoor comfort. In general, the proposed wall design provides a cost-effective and environmentally friendly solution for building envelopes. By combining sensible and latent heat storage through OSB and bio-based PCM layers, the system enhances thermal performance, reduces temperature fluctuations, and offers additional interior space, making it a promising approach for sustainable construction.
