الفهرس | Only 14 pages are availabe for public view |
Abstract One technique to reduce the demand for cooling load in buildings is inserting phase change materials (PCM) into building envelopes. In this research, the impact of integrating a PCM layer into a traditional wall in Egypt on peak and average cooling load is numerically examined by a finite volume technique using Crank-Nicolson method for discretization coded in MATLAB software. Simulations are performed based on three scenarios. First, investigate the performance of eight different commercial PCMs at three different configurations based on the position of the PCM in the base wall (Inner PCM, Middle PCM, and Outer PCM). Also, the effect of PCM on different wall orientations (North, East, South, and West wall), the effect of PCM layer thickness (1 cm, 2 cm, 3 cm, and 4 cm), and the impact of the PCMs at summer and winter. Second, establish selection curves using an approximated specific heat capacity curve to facilitate the comparison between the thermal performance of all types of PCMs. Third, investigate the impact of allowing water to flow into the PCM layer on the thermal performance. The results show that PCM-5 (conductivity=0.08 W.m-1.K-1, Latent heat= 88.4 kJ.kg-1, melting temperature=24 ˚C) has the best performance in reducing the average heat transmission under the examined weather conditions. Otherwise, the highest reduction in heat flow to the room in June could be achieved if water is allowed to flow into PCM-4 (conductivity=0.2 W.m-1.K-1), Latent heat= 165 kJ.kg-1, melting temperature=27.5 ˚C) from 4 AM to 6 AM. |