Yangyang Li , Ran Ju , Chongtao Liu , Xiuping Tao , Jianchao Song
{"title":"探讨地源热泵和精密送风系统在奶牛舍热应激缓解中的应用潜力。","authors":"Yangyang Li , Ran Ju , Chongtao Liu , Xiuping Tao , Jianchao Song","doi":"10.1016/j.jtherbio.2024.104039","DOIUrl":null,"url":null,"abstract":"<div><div>Maintaining an optimal indoor thermal environment is crucial for enhancing the welfare and productivity of livestock in intensive breeding farms. This paper investigated the application of a combined geothermal heat pump with a precision air supply (GHP-PAS) system for cooling dairy cows on a dairy farm. The effectiveness of the GHP-PAS system in mitigating heat stress in lactating dairy cattle, along with its energy performance and local cooling efficiency in the free stalls were evaluated. A total of 140 multiparous lactating Holstein cows was tested in two groups. One group was housed in a barn equipped with a GHP-PAS system (GP barn, n = 70), and the other was housed in a barn with a conventional fan-sprinkling system (FS barn, n = 70). Results showed that the ambient temperature of both GP and FS barns were lower than that outside the barn (<em>P</em> < 0.05), with no significant difference between the GP and FS barns (<em>P</em> > 0.05). Compared to cows in the FS barn, those in the GP barn exhibited lower skin temperature, rectal temperature, and respiratory rate (<em>P</em> < 0.05). The mean temperature difference between outflow and inflow water was 2.56 °C of the GHP unit. The average energy efficiency ratios (EER) of the GHP unit and the GHP-PAS system were 5.03 and 2.92, respectively. The daily average electricity consumption was 20.4 ± 1.0 kWh. The field test results indicated that the airflow from a single nozzle of the GHP-PAS system effectively covered a stall space with an average width of 1.84 m at a cow reclining height of 0.5 m, with an average air velocity of 1 m/s. The per-cow hourly electricity consumption for cooling was 2.04 kWh for the GHP-PAS system and 0.36 kWh for the FS system, highlighting that the GHP-PAS system is approximately 5.6 times more energy-intensive than the FS system. In conclusion, the GHP-PAS system showed the potential for alleviating heat stress in dairy cows. Further research is needed to enhance the energy efficiency and cooling effectiveness of the current GHP-PAS system.</div></div>","PeriodicalId":17428,"journal":{"name":"Journal of thermal biology","volume":"127 ","pages":"Article 104039"},"PeriodicalIF":2.9000,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Investigating the potential of geothermal heat pump and precision air supply system for heat stress abatement in dairy cattle barns\",\"authors\":\"Yangyang Li , Ran Ju , Chongtao Liu , Xiuping Tao , Jianchao Song\",\"doi\":\"10.1016/j.jtherbio.2024.104039\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Maintaining an optimal indoor thermal environment is crucial for enhancing the welfare and productivity of livestock in intensive breeding farms. This paper investigated the application of a combined geothermal heat pump with a precision air supply (GHP-PAS) system for cooling dairy cows on a dairy farm. The effectiveness of the GHP-PAS system in mitigating heat stress in lactating dairy cattle, along with its energy performance and local cooling efficiency in the free stalls were evaluated. A total of 140 multiparous lactating Holstein cows was tested in two groups. One group was housed in a barn equipped with a GHP-PAS system (GP barn, n = 70), and the other was housed in a barn with a conventional fan-sprinkling system (FS barn, n = 70). Results showed that the ambient temperature of both GP and FS barns were lower than that outside the barn (<em>P</em> < 0.05), with no significant difference between the GP and FS barns (<em>P</em> > 0.05). Compared to cows in the FS barn, those in the GP barn exhibited lower skin temperature, rectal temperature, and respiratory rate (<em>P</em> < 0.05). The mean temperature difference between outflow and inflow water was 2.56 °C of the GHP unit. The average energy efficiency ratios (EER) of the GHP unit and the GHP-PAS system were 5.03 and 2.92, respectively. The daily average electricity consumption was 20.4 ± 1.0 kWh. The field test results indicated that the airflow from a single nozzle of the GHP-PAS system effectively covered a stall space with an average width of 1.84 m at a cow reclining height of 0.5 m, with an average air velocity of 1 m/s. The per-cow hourly electricity consumption for cooling was 2.04 kWh for the GHP-PAS system and 0.36 kWh for the FS system, highlighting that the GHP-PAS system is approximately 5.6 times more energy-intensive than the FS system. In conclusion, the GHP-PAS system showed the potential for alleviating heat stress in dairy cows. Further research is needed to enhance the energy efficiency and cooling effectiveness of the current GHP-PAS system.</div></div>\",\"PeriodicalId\":17428,\"journal\":{\"name\":\"Journal of thermal biology\",\"volume\":\"127 \",\"pages\":\"Article 104039\"},\"PeriodicalIF\":2.9000,\"publicationDate\":\"2025-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of thermal biology\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0306456524002572\",\"RegionNum\":2,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of thermal biology","FirstCategoryId":"99","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0306456524002572","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOLOGY","Score":null,"Total":0}
Investigating the potential of geothermal heat pump and precision air supply system for heat stress abatement in dairy cattle barns
Maintaining an optimal indoor thermal environment is crucial for enhancing the welfare and productivity of livestock in intensive breeding farms. This paper investigated the application of a combined geothermal heat pump with a precision air supply (GHP-PAS) system for cooling dairy cows on a dairy farm. The effectiveness of the GHP-PAS system in mitigating heat stress in lactating dairy cattle, along with its energy performance and local cooling efficiency in the free stalls were evaluated. A total of 140 multiparous lactating Holstein cows was tested in two groups. One group was housed in a barn equipped with a GHP-PAS system (GP barn, n = 70), and the other was housed in a barn with a conventional fan-sprinkling system (FS barn, n = 70). Results showed that the ambient temperature of both GP and FS barns were lower than that outside the barn (P < 0.05), with no significant difference between the GP and FS barns (P > 0.05). Compared to cows in the FS barn, those in the GP barn exhibited lower skin temperature, rectal temperature, and respiratory rate (P < 0.05). The mean temperature difference between outflow and inflow water was 2.56 °C of the GHP unit. The average energy efficiency ratios (EER) of the GHP unit and the GHP-PAS system were 5.03 and 2.92, respectively. The daily average electricity consumption was 20.4 ± 1.0 kWh. The field test results indicated that the airflow from a single nozzle of the GHP-PAS system effectively covered a stall space with an average width of 1.84 m at a cow reclining height of 0.5 m, with an average air velocity of 1 m/s. The per-cow hourly electricity consumption for cooling was 2.04 kWh for the GHP-PAS system and 0.36 kWh for the FS system, highlighting that the GHP-PAS system is approximately 5.6 times more energy-intensive than the FS system. In conclusion, the GHP-PAS system showed the potential for alleviating heat stress in dairy cows. Further research is needed to enhance the energy efficiency and cooling effectiveness of the current GHP-PAS system.
期刊介绍:
The Journal of Thermal Biology publishes articles that advance our knowledge on the ways and mechanisms through which temperature affects man and animals. This includes studies of their responses to these effects and on the ecological consequences. Directly relevant to this theme are:
• The mechanisms of thermal limitation, heat and cold injury, and the resistance of organisms to extremes of temperature
• The mechanisms involved in acclimation, acclimatization and evolutionary adaptation to temperature
• Mechanisms underlying the patterns of hibernation, torpor, dormancy, aestivation and diapause
• Effects of temperature on reproduction and development, growth, ageing and life-span
• Studies on modelling heat transfer between organisms and their environment
• The contributions of temperature to effects of climate change on animal species and man
• Studies of conservation biology and physiology related to temperature
• Behavioural and physiological regulation of body temperature including its pathophysiology and fever
• Medical applications of hypo- and hyperthermia
Article types:
• Original articles
• Review articles