已知大连某地区,室内温度为24oC,相对温度为60%;室外温度为
16.9oC,相对湿度为60%,试计算围护结构内部各层的温度及水蒸气
分压。 序号
材料层
dm WmK
SWm2K gmhPa
1 钢筋混凝土 0.20 1.74 17.20
0.0000158
双面经界面砂浆
2
处理的竖向凹槽 EPS板
抹面胶浆复合玻纤网格布
0.042 0.36
0.0000162
3 0.01 0.045 0.75
0.0004880 0.0000443
4 涂料或饰面砂浆 0.02 0.81 10.07
n1.00;解:由题意得ti21oC,查温差修正系数n值表得: te16.9oC;
查室内空气与维护结构内表面之间的允许温差t(oC)表得:t6.0;及内表面换热阻Ri0.11m2KW;外表面换热阻Re0.04m2KW。
R1d10.200.115m2KW11.74d30.010.222m2KW 30.045d40.020.025m2KW40.81计算各材料层热阻:R3R4根据最小总热阻公式:
RomintitenR2416.91.000.110.750m2Kti6.0W
所以保温层热阻应有:
R2RominRiR1R3R4Re0.7500.110.1150.2220.0250.040.238m2KW考虑到墙面的灰缝影响,2、S2应予修正,查表得修正系数1.25
2'20.0421.250.053WmKS2'S20.361.250.450WmK
所以保温层厚度d2R22'0.013m;因为大连地区室外温度为
16.9oC,该墙体为III型,且热惰性指标D的取值范围为:D:1.6~4.0取d20.013m,R2d20.0130.310m2KW;20.042DRS0.11517.20.2220.360.2380.750.02510.072.49 满足墙体结构且Ro0.750m2KW所以围护结构内部温度分布为:
iti2ti3ti4tiRitite240.112416.918.00oCRo0.750RiR1tite240.110.0152416.917.18oCRo0.750RiR1R2tite240.110.0150.2222416.95.08oCRo0.750RiR1R2R3tite240.110.0150.2220.0252416.93.71oCRo0.750
计算各层材料蒸汽渗透阻:
H1H2H3H4d10.2012658.22m2hPag10.0000158d20.013802.47m2hPag20.0000162d30.0120.49m2hPag30.0004880d40.02451.47m2hPag40.0000443HoH1H2H3H412658.22802.4720.49451.4713932.65m2hPag查表得:当
ti24oC时,Ps2983.7Pa,则PiPs2983.760%1790.22Pate16.9oC时,Ps138.7Pa,则PePs138.760%83.22Pa且i18.00oC时,Psi2062.5Pa217.18oC时,Ps21961.2Pa35.08oC时,Ps3878.6Pa43.71oC时,Ps4791.9PaP2PiP3PiH1.22PiPe1790.2212658(1790.2283.22)239.36PaHo13932.65H1H2.22802.47PiPe1790.2212658(1790.2283.22)141.04PaHo13932.65
因篇幅问题不能全部显示,请点此查看更多更全内容