基于室外风力因素外墙最优保温厚度

Optimum insulation thickness of exterior wall based on outdoor wind factor

采用TRNSYS瞬态系统模拟软件计算室外风速和风向对外墙传热的影响,对南京住宅建筑4个朝向采用2种保温材料计算全年加热和冷却负荷。基于现值因子最大程度减少加热冷却能耗和保温成本得到最优保温厚度。计算采用最优保温厚度20年生命周期节省经济成本和保温投资回收期。结果表明:对于EPS和XPS两种保温材料,最优保温厚度分别为10.5~12.1 cm和6.1~7.1 cm,生命周期节省经济成本分别为218.4~315.5元/m^2和196.8~284.2元/m^2,保温投资回收期分别为1.7~2.6年和2.1~3.2年。室外风力因素对最优保温厚度影响不大而对全年冷热负荷以及寿命周期节省经济成本影响较大。

TRNSYS transient simulation software is employed to investigate the effect of outdoor wind speed and wind direction on the external wall heat transfer process. Annual heating and cooling transmission load are calculated for residential building with four orientations and two type of insulation materials in Nanjing. The optimum insulation thickness is achieved by minimizing the heating and cooling energy consumption and insulation cost based on the present worth method. Life cycle economic cost savings over a lifetime of 20 years and insulation payback periods are calculated. The results indicate that for EPS and XPS these two kinds of insulation materials,optimum insulation thicknesses vary between 10.5 cm and 12.1 cm,6.1 cm and 7.1 cm：life cycle savings vary between 218.4 yuan/na2 and 315.5 yuan/m^2,196.8 yuan/m^2 and 284.2 yuan/m^2：payback periods vary between 1.7 years and 2.6 years,2.1 years and 3.2 years,respectively. Outdoor wind factor has a small effect on the optimum insulation thickness while it has a great influence on the annual heating and cooling transmission load and life cycle economic cost saving.