Heat Transfer Research, cilt.56, sa.17, ss.1-14, 2025 (SCI-Expanded)
Recently, in the search for ecological and energy-efficient solutions, sandwich structures offer significant advantages in the thermal insulation of buildings. By reducing heat transfer, these structures reduce energy consumption and save energy costs. Simultaneously, by augmenting the use of materials, they both reduce costs and mitigate the impact on the environment. Additive manufacturing (AM) technologies, the ideal production technique for these structures, offer flexible and customizable design possibilities and the most suitable solutions can be applied according to the thermal insulation needs of the buildings. The goal of this study is to examine the efficiency of different unit cell designs in heat transfer by computational fluid dynamics (CFD) and numerical calculations, taking into account the environmental benefits of sandwich structures such as thermal conductivity, structural characteristics, air permeability rate, and recyclability. Additionally, body-centered cubic (BCC) and 3D re-entrant honeycomb unit cells are utilized in the design of sandwich structures and the effects of units on thermal insulation (TI) are searched. The results have observed that the void ratio in sandwich structures makes a significant contribution to internal thermal energy storage. The use of re-entrant unit cells in TI applications results in lower room temperature values compared to BCC-based sandwich structures. The average TI value of the room designed with a 3D re-entrant honeycomb sandwich structure is determined as approximately 42.03°C. In contrast, the TI value of the room designed with BCC sandwich structure is stated as 37.48°C. Therefore, the internal temperature of the room designed with 3D re-entrant unit cell is about 4.55°C lower than the room designed with BCC unit, and the heat loss efficiency is calculated to be 10.8% better.