In this study,based on the established heat transfer and mechanical stress models,thermal stress distribution of glazing unit filled with paraffin was studied for various temperature differences between indoor and out...In this study,based on the established heat transfer and mechanical stress models,thermal stress distribution of glazing unit filled with paraffin was studied for various temperature differences between indoor and outdoor conditions.The strain produced on the surface of glazing unit filled with paraffin varies greatly in the outdoor temperature range of-30℃-40 ℃.Furthermore,phase change material(PCM) layer between the glass panes significantly affects the strain values at different temperatures,which can respectively reach up to about 250×10^(-6) and down to-300×10^(-6) for tensile and compressive strains once the paraffin is in liquid state.Additionally,impacts of boundary conditions on the strain values are more pronounced within the distance of 0.01 m from the edges of the glazing window.The presented model and outcomes can be used as a guide to simulate thermal stress in glazing units filled with paraffin.展开更多
中空玻璃幕墙合理设计的一个关键环节是合理确定玻璃面板的荷载分配,而现阶段不同国家和地区对于中空玻璃幕墙设计的相关规定有较大差别。为了明确其差异性,对比了中、美和欧现行中空玻璃幕墙设计规范、标准和基于功的互等定理的理论研...中空玻璃幕墙合理设计的一个关键环节是合理确定玻璃面板的荷载分配,而现阶段不同国家和地区对于中空玻璃幕墙设计的相关规定有较大差别。为了明确其差异性,对比了中、美和欧现行中空玻璃幕墙设计规范、标准和基于功的互等定理的理论研究在荷载分配机理、适用范围的异同,并以某工程实例的三玻两腔幕墙为例,对荷载分配结果进行对比和参数化分析。研究结果表明:EN 16612-2019是目前考虑影响荷载分配因素最为全面的标准;JGJ 255—2012与《Code of practice for structure use of glass》考虑了放大系数使分配结果偏保守;在初始空腔体积V=0.021 m3的中空玻璃幕墙中,考虑气体压缩性影响的玻璃分配的荷载比例较具有更大初始空腔体积的中空玻璃幕墙提高10%以上;两空腔气温为70℃的极端环境下,空腔气温变化引起的外侧外片玻璃的温度荷载为-0.3 kPa,远小于玻璃分配的风荷载±1.76 kPa。此外,基于现有规范、标准的适用范围,对完善中空幕墙设计需进一步考虑的问题提出了建议,包括考虑不同玻璃的几何外形及外荷载类型等。展开更多
基金Project(52078110) supported by the National Natural Science Foundation of ChinaProject(2018KYQD15) supported by Beibu Gulf Universityt,China。
文摘In this study,based on the established heat transfer and mechanical stress models,thermal stress distribution of glazing unit filled with paraffin was studied for various temperature differences between indoor and outdoor conditions.The strain produced on the surface of glazing unit filled with paraffin varies greatly in the outdoor temperature range of-30℃-40 ℃.Furthermore,phase change material(PCM) layer between the glass panes significantly affects the strain values at different temperatures,which can respectively reach up to about 250×10^(-6) and down to-300×10^(-6) for tensile and compressive strains once the paraffin is in liquid state.Additionally,impacts of boundary conditions on the strain values are more pronounced within the distance of 0.01 m from the edges of the glazing window.The presented model and outcomes can be used as a guide to simulate thermal stress in glazing units filled with paraffin.
文摘中空玻璃幕墙合理设计的一个关键环节是合理确定玻璃面板的荷载分配,而现阶段不同国家和地区对于中空玻璃幕墙设计的相关规定有较大差别。为了明确其差异性,对比了中、美和欧现行中空玻璃幕墙设计规范、标准和基于功的互等定理的理论研究在荷载分配机理、适用范围的异同,并以某工程实例的三玻两腔幕墙为例,对荷载分配结果进行对比和参数化分析。研究结果表明:EN 16612-2019是目前考虑影响荷载分配因素最为全面的标准;JGJ 255—2012与《Code of practice for structure use of glass》考虑了放大系数使分配结果偏保守;在初始空腔体积V=0.021 m3的中空玻璃幕墙中,考虑气体压缩性影响的玻璃分配的荷载比例较具有更大初始空腔体积的中空玻璃幕墙提高10%以上;两空腔气温为70℃的极端环境下,空腔气温变化引起的外侧外片玻璃的温度荷载为-0.3 kPa,远小于玻璃分配的风荷载±1.76 kPa。此外,基于现有规范、标准的适用范围,对完善中空幕墙设计需进一步考虑的问题提出了建议,包括考虑不同玻璃的几何外形及外荷载类型等。
