نوع مقاله : مقاله پژوهشی
نویسندگان
1 استادیار و عضو هیئت علمی گروه معماری، دانشکده هنر و معماری، دانشگاه یزد، یزد، ایران
2 دانشجوی کارشناسی ارشد مهندسی معماری و انرژی، دانشکده هنر و معماری، دانشگاه یزد، یزد، ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Extended Abstract
1. Introduction
Cooling systems in hot and arid climate buildings play a significant role in climate change due to their high water and energy consumption. Although evaporative coolers are effective at cooling the space, they are often uncontrollable and ineffective during periods of low cooling demand, which can result in overcooling of the indoor space. Previous studies have paid less attention to reducing water consumption in evaporative cooling systems. Therefore, a study has been conducted to propose a hybrid cooling system for reducing water consumption in evaporative cooling of buildings in hot and arid climates. This study aims to add new features to the existing cooling system in hot and arid climates, transforming it into a more suitable cooling system that can significantly reduce water and energy consumption while improving indoor thermal conditions.
2. Research Methodology
This study was conducted on a sample residential building in the hot and arid climate of Yazd City for five days (24 hours per day in August and September). The building had a 3D panel structure, which acted as an insulator. A field study was conducted during the summer season in two similar rooms. Environmental indicators, such as temperature, relative humidity, air velocity, and water consumption by the evaporative cooler, were measured using relevant devices. The experiment consisted of two stages: evaluating the initial state of the rooms and assessing the performance of the evaporative cooler and hybrid system compared to one-sided natural ventilation.
3. Results and discussion
When the rooms were examined for uniformity, among the three tested states, one-sided natural ventilation and evaporative cooling based on natural ventilation had little effect on reducing the space temperature, and only the evaporative cooler had an effective role in reducing the room's temperature. By using the evaporative cooler for 24 hours, on average, the temperature reduction was 8°C compared to the one-sided natural ventilation, and the relative humidity increased by 23%. The measurements indicated that during a 24-hour period, the evaporative cooler consumed 290 liters of water and 10kWh of electricity.
4. Conclusion
The performance of evaporative cooling systems was compared to one-sided natural ventilation as the base case. The proposed hybrid system achieved an average temperature reduction of 5.5 °C and an increase in relative humidity of 16-18 % compared to the one-sided natural ventilation. While the hybrid system had lower temperature fluctuations compared to the evaporative cooler, on average, the temperature decreased more and the relative humidity increased more with the use of the evaporative cooler. By examining the effect of this issue on the room, the evaporative cooler's performance was excessive most of the time, making it unsuitable for providing thermal comfort. In contrast, the hybrid system provided better thermal comfort than the evaporative cooler in most hours, even with an outdoor environment temperature ranging from 32°C to 30°C. Using the hybrid system instead of the evaporative cooler can reduce electricity consumption by 74% and water consumption by 96%. In other words, it reduced water consumption to 10 liters/day and electricity consumption to 2.6 kWh. Importantly, this system is designed with auxiliary fans and components related to the evaporative cooler, and it can be easily implemented as a simple and low-cost solution with high performance and a low payback period without creating limitations in the design. Therefore, it will be a suitable replacement for current mechanical evaporative cooling systems for the afternoon, evening, and early morning hours (between 18:00 to 08:00) in warm summer and spring months.
کلیدواژه‌ها [English]
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