In this work, we present a numerical study of the thermal behavior of a hollow block with or without phase change material (PCM) in the Sahelian zone.The PCMs used in this study are RT27 paraffin and hydrated salt with a melting temperature of 27°C and 29.9°C respectively and a latent heat of fusion of 179kJ/kg and 184kJ/kg. The equations obtained were adimensionalized then discretized by the finite element method and solved on the COMSOL software. We were first interested in the study of the thermal phase shift, the damping and the evolution of the temperature at the level of the internal wall. In a second phase, we conducted a comparative study between hollow block containing PCM and other construction materials (adobe, BTC and BLT) used in Burkina Faso. The numerical results obtained show that the temperature of the internal wall of a hollow block containing RT27 is lower than that of a hollow block without PCM, hollow block containing hydrated salt, BTC, BLT and adobe with respectively a temperature difference of 8.354°C; 3.39°C; 5.79°C; 3.97°C and 3.92°C and the difference in terms of phase shift is 1h18min, 6min, 24min, 42min and 6min for the hollow block containing RT27, the hollow block containing hydrated salt, BTC, BLT and adobe.Therefore, the integration of PCM in building materials increases their thermal inertia

Numerical simulation, hollow block;, phase change materials, thermal, COMSOL