Wet bulb globe temperature(WBGT)is a comprehensive index obtained mainly from three parameters:black globe temperature(Tg),wet bulb temperature(Tw),and dry bulb temperature(Ta).While in field observation and numerical...Wet bulb globe temperature(WBGT)is a comprehensive index obtained mainly from three parameters:black globe temperature(Tg),wet bulb temperature(Tw),and dry bulb temperature(Ta).While in field observation and numerical simulation,black globe temperature and wet bulb temperature were not easy to obtain,so WBGT was difficult to measure and calculate directly.In order to solve this problem,air dry bulb temperature,wet bulb temperature,globe temperature,relative humidity,mean air velocity,solar radiation and wet bulb globe temperature were collected during the summer(July)in Guangzhou.Correlation analysis and regression analysis were used to get a simplified method to calculate WBGT.The results showed that dry bulb temperature,relative humidity,solar radiation and WBGT were interrelated to some extent.These three parameters could be used in the simplified method to predict WBGT,and the linear correlation and precision of this model were high.In addition,we used the measured data to verify the simplified method,and the results showed that the error of the calculated value and the measured value was all below 5%,which means the simplified calculating method is feasible and can be used in field observation and simulation research of urban thermal environment.展开更多
基于冷喷涂技术,提出了一种替代传统100 W白炽灯的新型12 W LED球泡灯,其散热器由纯铝板裁剪和弯折而成。在分析铜基板内部结构基础上,借助ANSYS软件模拟不同覆铜层厚度和不同形状散热器的球泡灯温度场,获得了具有最低芯片结温的LED球...基于冷喷涂技术,提出了一种替代传统100 W白炽灯的新型12 W LED球泡灯,其散热器由纯铝板裁剪和弯折而成。在分析铜基板内部结构基础上,借助ANSYS软件模拟不同覆铜层厚度和不同形状散热器的球泡灯温度场,获得了具有最低芯片结温的LED球泡灯。研究结果表明,铜基板厚度一定时,芯片结温随覆铜层厚度的增加而降低。选择纯铝质散热器和增加覆铜层厚度可使LED球泡灯的结温降低为71.25℃,低于芯片安全温度85℃,满足散热和照明习惯要求。展开更多
基金Supported by the National Natural Science Foundation of China(50538040,50720165805,50808083)the 111 project(111-2-13)State Key Laboratory of Subtropical Building(2008ZB14)
文摘Wet bulb globe temperature(WBGT)is a comprehensive index obtained mainly from three parameters:black globe temperature(Tg),wet bulb temperature(Tw),and dry bulb temperature(Ta).While in field observation and numerical simulation,black globe temperature and wet bulb temperature were not easy to obtain,so WBGT was difficult to measure and calculate directly.In order to solve this problem,air dry bulb temperature,wet bulb temperature,globe temperature,relative humidity,mean air velocity,solar radiation and wet bulb globe temperature were collected during the summer(July)in Guangzhou.Correlation analysis and regression analysis were used to get a simplified method to calculate WBGT.The results showed that dry bulb temperature,relative humidity,solar radiation and WBGT were interrelated to some extent.These three parameters could be used in the simplified method to predict WBGT,and the linear correlation and precision of this model were high.In addition,we used the measured data to verify the simplified method,and the results showed that the error of the calculated value and the measured value was all below 5%,which means the simplified calculating method is feasible and can be used in field observation and simulation research of urban thermal environment.
文摘基于冷喷涂技术,提出了一种替代传统100 W白炽灯的新型12 W LED球泡灯,其散热器由纯铝板裁剪和弯折而成。在分析铜基板内部结构基础上,借助ANSYS软件模拟不同覆铜层厚度和不同形状散热器的球泡灯温度场,获得了具有最低芯片结温的LED球泡灯。研究结果表明,铜基板厚度一定时,芯片结温随覆铜层厚度的增加而降低。选择纯铝质散热器和增加覆铜层厚度可使LED球泡灯的结温降低为71.25℃,低于芯片安全温度85℃,满足散热和照明习惯要求。
