Nowadays,people still rely on traditional heating methods in rural areas of northern China,such as Kang(bed-stoves) and burning caves in cold winter.Field measurements of indoor environment were carried out in several...Nowadays,people still rely on traditional heating methods in rural areas of northern China,such as Kang(bed-stoves) and burning caves in cold winter.Field measurements of indoor environment were carried out in several rural houses with burning-cave-coil-Kang coupling heating system in northern China.The results show that this system is able to realize the graded use of internal energy of burning cave.The temperature of supply pipe water ranged from 30 ℃ to 50 ℃ which met the demands in 74.7% of time.The surface temperature of Kang maintained at above 25 ℃.Compared with traditional burning cave,using burning-cave-coil-Kang coupled with heating system has a higher thermal efficiency of 48.9%,which is 8.32% higher than the traditional one.展开更多
[目的]核电厂汽水管线一般在管道外壁加装保温层,从而提高换热效率。目前对于铁磁性管道的检测手段主要为常规超声及超声导波,检测前需要将管道外壁保温层拆除,导致检测工期延长,人力成本增加,无法达到核电厂高质量发展的要求。核电厂...[目的]核电厂汽水管线一般在管道外壁加装保温层,从而提高换热效率。目前对于铁磁性管道的检测手段主要为常规超声及超声导波,检测前需要将管道外壁保温层拆除,导致检测工期延长,人力成本增加,无法达到核电厂高质量发展的要求。核电厂脉冲涡流技术的应用可以省去保温层的拆装,实现不停机在线筛查。检测线圈的放置方式对缺陷的检出能力是脉冲涡流技术重要指标。[方法]文章利用ANSYS中的Maxwell模块进行管件建模及仿真,分别设计同轴式与垂直式检测线圈,保持提离距离、材料一致及其他条件一致下,模拟脉冲涡流对平底缺陷的检测能力。选取核电厂样管进行同轴式与垂直式脉冲涡流测试,将脉冲涡流(Pulsed Eddy Current Testing,PECT)测试结果与超声测厚进行复核,对比两种线圈放置方式对脉冲涡流检测的影响。[结果]研究表明:垂直式线圈相对于同轴式线圈对缺陷检出效果更佳。[结论]核电厂脉冲涡流技术的应用对脉冲涡流技术在核电领域实施具有重要意义。展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.51178075)the Fundamental Research Funds for the Central Universities(Grant No.DUT17RW118)
文摘Nowadays,people still rely on traditional heating methods in rural areas of northern China,such as Kang(bed-stoves) and burning caves in cold winter.Field measurements of indoor environment were carried out in several rural houses with burning-cave-coil-Kang coupling heating system in northern China.The results show that this system is able to realize the graded use of internal energy of burning cave.The temperature of supply pipe water ranged from 30 ℃ to 50 ℃ which met the demands in 74.7% of time.The surface temperature of Kang maintained at above 25 ℃.Compared with traditional burning cave,using burning-cave-coil-Kang coupled with heating system has a higher thermal efficiency of 48.9%,which is 8.32% higher than the traditional one.
文摘[目的]核电厂汽水管线一般在管道外壁加装保温层,从而提高换热效率。目前对于铁磁性管道的检测手段主要为常规超声及超声导波,检测前需要将管道外壁保温层拆除,导致检测工期延长,人力成本增加,无法达到核电厂高质量发展的要求。核电厂脉冲涡流技术的应用可以省去保温层的拆装,实现不停机在线筛查。检测线圈的放置方式对缺陷的检出能力是脉冲涡流技术重要指标。[方法]文章利用ANSYS中的Maxwell模块进行管件建模及仿真,分别设计同轴式与垂直式检测线圈,保持提离距离、材料一致及其他条件一致下,模拟脉冲涡流对平底缺陷的检测能力。选取核电厂样管进行同轴式与垂直式脉冲涡流测试,将脉冲涡流(Pulsed Eddy Current Testing,PECT)测试结果与超声测厚进行复核,对比两种线圈放置方式对脉冲涡流检测的影响。[结果]研究表明:垂直式线圈相对于同轴式线圈对缺陷检出效果更佳。[结论]核电厂脉冲涡流技术的应用对脉冲涡流技术在核电领域实施具有重要意义。