The utilisation of waste in green sustainable technology can provide a clean environment and support energy demand.This work aims to design and analyse the performance of a developed indirect flat-plate Solar Air Heat...The utilisation of waste in green sustainable technology can provide a clean environment and support energy demand.This work aims to design and analyse the performance of a developed indirect flat-plate Solar Air Heater(SAH)integrated with an internal thermal storage unit using Waste Automotive Oil(WAO).The SAH was designed based on the circulation of confined air around the internal thermal storage unit due to the updraft effects of hot air.Two SAHs were tested to compare the performance of WAO and water,with the results being compared to previous work that utilised phase change material.Results showed that WAO responds faster in the early stage,while water has slightly higher daytime efficiency,with a maximum temperature of 60℃,while WAO reached a maximum temperature of 76℃.During the discharge cycle,WAO achieved an efficiency of 65.7%,while the water’s efficiency 73.2% within the same period.The highest outlet air temperatures recorded were 43℃ for WAO and 33.8℃ for water.These findings support that water is suitable for applications requiring rapid thermal charging,while WAO offers extended thermal stability.The study highlights the feasibility of using low-cost materials,such as WAO and water,to enhance the performance of solar energy systems,thereby making them more viable for industrial applications like drying and heating.展开更多
Despite significant advancements in solar collector technology,persistent challenges remain in improving the overall efficiency of solar systems.This paper investigates the use of mini-channel aluminum tubes mounted o...Despite significant advancements in solar collector technology,persistent challenges remain in improving the overall efficiency of solar systems.This paper investigates the use of mini-channel aluminum tubes mounted on the reflective surface as preliminary heating stages to enhance the overall system thermal performance.Experimental assessments were conducted with flow rates ranging from 0.1 to 0.8 LPM and tilt angles of 180°South and 225°Southwest in Al-Kut,Iraq,from 9:00 AM to 2:00 PM.Fluid flows sequentially through five flat aluminum tubes totaling 50 channels,named stage-1,then flows through four aluminum tubes totaling 40 channels,named stage-2,and lastly through the copper tube receiver,named stage-3.Results indicate that the copper tube contributes 65%–80% of total heating,while the aluminum tubes contribute 20%–35%.The maximum thermal efficiency reached 84%at a flow rate of 0.5 LPM and a tilt angle of 180°South at 1:00 PM.The pressure drop behavior was analyzed through three stages with different flow distributions.In stages 1 and 2,the pressure drop increased linearly with flow rate.In stage-3,the pressure drop rose more sharply with flow rate showing a nonlinear trend.The results contribute to the optimization of solar thermal systems by clarifying the roles of flow rate,collector orientation,and the use of mini-channel aluminum tubes in enhancing thermal efficiency.This study contributes to solar thermal technology by showing that the use of aluminum preheating tubes in a modified PTC can enhance thermal performance and provide sustainable energy solutions.展开更多
针对定日镜风致振动会降低光热电站发电效率的问题,开发一款基于深度强化学习的控制算法抑制定日镜振动。首先构建吸振器-定日镜动力学模型的Open AI Gym训练环境,完成模拟状态下深度强化学习模型的训练并验证随机振动控制效果。其次搭...针对定日镜风致振动会降低光热电站发电效率的问题,开发一款基于深度强化学习的控制算法抑制定日镜振动。首先构建吸振器-定日镜动力学模型的Open AI Gym训练环境,完成模拟状态下深度强化学习模型的训练并验证随机振动控制效果。其次搭建实验系统,通过构建包含定日镜振动特征、控制信号、奖励值与终止状态的数据集,训练智能体学习吸振器的电-磁-刚度机理。最后编写模型调用脚本,在LabVIEW主系统调用函数节点完成混合编程。结果显示在12.3 Hz的外界激励下,该算法可在1 s内计算出最优的控制信号,将±0.42 m/s^(2)的振幅降低到±0.29 m/s^(2)。该算法利用神经网络实现定日镜振动的跟踪控制,对强化学习算法落地及定日镜结构保护有一定参考意义。展开更多
文摘The utilisation of waste in green sustainable technology can provide a clean environment and support energy demand.This work aims to design and analyse the performance of a developed indirect flat-plate Solar Air Heater(SAH)integrated with an internal thermal storage unit using Waste Automotive Oil(WAO).The SAH was designed based on the circulation of confined air around the internal thermal storage unit due to the updraft effects of hot air.Two SAHs were tested to compare the performance of WAO and water,with the results being compared to previous work that utilised phase change material.Results showed that WAO responds faster in the early stage,while water has slightly higher daytime efficiency,with a maximum temperature of 60℃,while WAO reached a maximum temperature of 76℃.During the discharge cycle,WAO achieved an efficiency of 65.7%,while the water’s efficiency 73.2% within the same period.The highest outlet air temperatures recorded were 43℃ for WAO and 33.8℃ for water.These findings support that water is suitable for applications requiring rapid thermal charging,while WAO offers extended thermal stability.The study highlights the feasibility of using low-cost materials,such as WAO and water,to enhance the performance of solar energy systems,thereby making them more viable for industrial applications like drying and heating.
文摘Despite significant advancements in solar collector technology,persistent challenges remain in improving the overall efficiency of solar systems.This paper investigates the use of mini-channel aluminum tubes mounted on the reflective surface as preliminary heating stages to enhance the overall system thermal performance.Experimental assessments were conducted with flow rates ranging from 0.1 to 0.8 LPM and tilt angles of 180°South and 225°Southwest in Al-Kut,Iraq,from 9:00 AM to 2:00 PM.Fluid flows sequentially through five flat aluminum tubes totaling 50 channels,named stage-1,then flows through four aluminum tubes totaling 40 channels,named stage-2,and lastly through the copper tube receiver,named stage-3.Results indicate that the copper tube contributes 65%–80% of total heating,while the aluminum tubes contribute 20%–35%.The maximum thermal efficiency reached 84%at a flow rate of 0.5 LPM and a tilt angle of 180°South at 1:00 PM.The pressure drop behavior was analyzed through three stages with different flow distributions.In stages 1 and 2,the pressure drop increased linearly with flow rate.In stage-3,the pressure drop rose more sharply with flow rate showing a nonlinear trend.The results contribute to the optimization of solar thermal systems by clarifying the roles of flow rate,collector orientation,and the use of mini-channel aluminum tubes in enhancing thermal efficiency.This study contributes to solar thermal technology by showing that the use of aluminum preheating tubes in a modified PTC can enhance thermal performance and provide sustainable energy solutions.
