Study on determination of interfacial resistance for moisture behavior in Multilayered Building Wall

多层建筑墙体吸湿性能界面阻力测定研究

• 批准号: 14550589
• 负责人: TERASHIMA Takane
• 金额: $ 1.79万
• 依托单位: Mie University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14550589/
• 关键词: multilayered wall; internal condensation; moisture content; interfacial resistance; simultaneous heat and moisture transfer equation; numerical calculation; calcium silicate; cellular concrete; 二層壁体; 結露・再蒸発

Specimens which consist of two layers of calcium silicate board / cellular concrete are made as a multilayered wall experimental model. The change of internal moisture content in specimen under the condensation and re-evaporation process was measured and then analyzed by numerical calculation using two calculation models. Lastly the interfacial resistance value is determined by sensitive analysis. And the followings are found.Measured values of average moisture content are influenced by the interfaces between two layers. The position of the interface in specimen influences the moisture content gradient in the initial condensation process and re-evaporation process. And the specimen which is consisted of different materials is more influenced than same materials. As for distribution, the internal moisture content shows the tendency to bipolarize.Measured values of average moisture content change is compared to the calculated values by two models. Model 1 is assumed that there is a continuous moisture transfer between two layers, and Model 2 is assumed that internal moisture flows through the interfacial resistance at the interface between two layers. Consequently, calculated values by Model 1 agree with measured average values. But the bipolarized tendency of moisture content distribution cannot be described. Calculated values by Model 2 do not agree with measured average values in re-evaporation process but the bipolarized tendency of moisture content distribution was described well.Sensitive analysis by calculation model 2 was conducted and the interfacial resistance values for heat and moisture flux was determined.

由两层硅酸钙板/多孔混凝土组成的试件作为多层墙体实验模型。采用两种计算模型对试样在冷凝和再蒸发过程中内部含水率的变化进行了测量和数值计算分析。最后通过灵敏分析确定界面电阻值。结果如下。平均含水率的测量值受两层界面的影响。试样中界面的位置影响了初始凝结过程和再蒸发过程中的含水率梯度。由不同材料组成的试样比由相同材料组成的试样受影响更大。在分布上，内部含水率呈两极化趋势。将两种模型的平均含水率变化实测值与计算值进行了比较。模型1假设两层之间存在连续的水分传递，模型2假设内部水分通过两层界面处的界面阻力流动。因此，模型1的计算值与实测平均值吻合。但含水率分布的双极化趋势无法描述。模型2的计算值与再蒸发过程的实测平均值不一致，但很好地描述了水分分布的两极化趋势。利用计算模型2进行了敏感性分析，确定了热湿通量的界面阻值。