포화 불균일성을 고려한 육계사 쿨링패드 시스템 성능 평가
Evaluation of Performance on Cooling Pad System According to Non-uniform Saturation of in Broiler House
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Heat stress in broiler houses during the summer can lead to reduced feed intake and feed efficiency, ultimately resulting in decreased productivity. To mitigate heat stress, cooling pads utilizing the evaporative cooling effect have been introduced in commercial broiler houses. In this study, the performance of cooling pads in an actual broiler house was evaluated, and a wind tunnel equipment was designed to precisely analyze their performance. The results revealed that in the broiler house with long cooling pads, the uneven distribution of water led to a decrease in cooling efficiency. Specifically, cooling efficiency was 81% when the cooling pads were wet enough but decreased to 49.6% as the water supply to the cooling pads was not proper. Furthermore, wind tunnel experiments showed that as the airflow speed increased from 0.64 mㆍs-1 to 1.86 mㆍs-1, the temperature reduction decreased from 8.3 °C to 6.6 °C. However, the mass transfer coefficient and heat transfer coefficient increased by 0.0019 mㆍh⁻¹ and 37.32 Wㆍm-²ㆍK⁻¹, respectively, indicating more active evaporation and greater heat removal due to higher airflow speed. Additionally, as relative humidity increased, the temperature reduction significantly decreased. When water was unevenly distributed across the cooling pad, the temperature reduction and cooling efficiency in areas without water were significantly reduced. These findings highlight the importance of maintaining uniform water distribution over the cooling pads to ensure desired cooling effects.
Abstract
Heat stress in broiler houses during the summer can lead to reduced feed intake and feed efficiency, ultimately resulting in decreased productivity. To mitigate heat stress, cooling pads utilizing the evaporative cooling effect have been introduced in commercial broiler houses. In this study, the performance of cooling pads in an actual broiler house was evaluated, and a wind tunnel equipment was designed to precisely analyze their performance. The results revealed that in the broiler house with long cooling pads, the uneven distribution of water led to a decrease in cooling efficiency. Specifically, cooling efficiency was 81% when the cooling pads were wet enough but decreased to 49.6% as the water supply to the cooling pads was not proper. Furthermore, wind tunnel experiments showed that as the airflow speed increased from 0.64 mㆍs-1 to 1.86 mㆍs-1, the temperature reduction decreased from 8.3 °C to 6.6 °C. However, the mass transfer coefficient and heat transfer coefficient increased by 0.0019 mㆍh⁻¹ and 37.32 Wㆍm-²ㆍK⁻¹, respectively, indicating more active evaporation and greater heat removal due to higher airflow speed. Additionally, as relative humidity increased, the temperature reduction significantly decreased. When water was unevenly distributed across the cooling pad, the temperature reduction and cooling efficiency in areas without water were significantly reduced. These findings highlight the importance of maintaining uniform water distribution over the cooling pads to ensure desired cooling effects.
참고문헌 (20)
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