严寒地区超低能耗建筑女儿墙优化设计OA

Taking the heat transfer coefficient of the thermal bridge line and the minimum temperature of the inner surface of the external wall(ensuring no condensation on the inner surface)as the evaluation indexes,the two-dimensional heat transfer model is used to calculate the change of the minimum tempera-ture of the inner surface of the external wall with the height of the inner insulation layer of the parapet,so as to determine the conditions for canceling the top insula-tion layer of the parapet.The three-dimensional heat transfer simulation method is used to determine the minimum thickness of the insulation layer of the exter-nal wall that meets the minimum temperature require-ments of the inner surface of the external wall under different outdoor temperature conditions.Under the same conditions,compared with the canceling of the top insulation layer of the parapet,retaining the top insula-tion layer of the parapet results in a lower heat transfer coefficient of the thermal bridge line,a higher minimum temperature on the inner surface of the external wall,and better insulation performance.When the height of the inner insulation layer of the parapet is 1 100 mm or more,the top insulation layer of the parapet can be canceled.When the height of the insulation layer on the inner side of the parapet wall is 1100 mm and there is no insulation layer on the top of the parapet:when the outdoor temperature is-26.9 ℃,the EPS board and PU board for external wall insulation can ensure that the minimum temperature of the inner surface of the ex-ternal wall is higher than the limit of 12 ℃ within their respective thickness ranges.When the outdoor temper-ature is-36.3 ℃,in order to ensure that the minimum temperature of the inner surface of the external wall is higher than 12℃,the minimum thickness of EPS board for external wall insulation is 340 mm,and the minimum thickness of PU board for external wall insu-lation is 260 mm.