Figures 70 to 73 illustrate that the rock bed can provide cool air, 5°C lower than the ambient temperature, from 10:00 am till 18:00 pm. From 18:00 pm, the ambient temperature drops gradually till the next day, 7:00 am. The rock remains warmer than the ambient air during the evening from 18:00 pm till 7:00 am due to the flywheel effect explained in paragraph 6.1.3. The core of the rock is warmer than the ambient air and cools down much slower than the ambient air due to the rock’s thermal mass. During the peak temperature of the ambient air at 13:00 pm, the air from the rock bed showed a temperature difference of 29% on day one, 29% on day two, and 28% on day three. The system cooled the ambient air on average 28,5% over the three days the system was tested.
6.3.4 CONCLUSION Using the solar heating system for cooling during the summer has shown positive results to cool the ambient air during the daytime by using the cooled ambient air during the night. The system also improves the indoor air quality by ventilating fresh ambient air through the system for 24 hours per day.
6.4 FULL EXPERIMENT - PART 4: ENCLOSED COOLING SYSTEM 6.4.1 INTRODUCTION Part 4 of the experiment will focus on an enclosed cooling system; this system will use the cool ambient air during the evening and circulate the internal air during the day. Figures 74 and 75 illustrate the enclosed cooling system for the day and night-time. As illustrated in Figure 74, the system will be enclosed to recirculate the cool air through the system. In Figure 75, it is illustrated that the system will be opened during the night-time to cool the rocks of the rock bed with means of cool ambient air.
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