Numerical Study of Effect of Kenaf Fiber Content and Size on the Thermal Inertia of Adobe Walls

This study aims to impact of adding kenaf fibers on the thermal performance of adobes. In a context of increasing research into sustainable, energy-efficient construction alternatives, adobes, raw earth bricks, are often considered. However, their thermal properties can be improved, hence our interest in exploring the use of plant fibers, such as kenaf, as reinforcement in the composition of adobes. Using a numerical model, we simulated the thermal behavior of these innovative materials. The simulation results were compared with those of the literature, and a maximum relative deviation of 2.3 % was obtained in the temperature at the outer surface. This highlights the accuracy and reliability of the numerical code used. The results indicate that the addition of the fibers results in a reduction and time shift of the peak flux densities at the outlet face of the adobe walls. A reduction of over 90 % in peak flux densities at the inner surface of the walls was achieved with 0.8 % kenaf fibers. This contributes significantly to reducing the temperature at the inner face of the walls, resulting in a reduction in the damping factor and an increase in the time lag with fiber size and content. This study thus demonstrates the potential of kenaf fiber-reinforced adobes as sustainable, energy-efficient building materials.