MU-KFTA01
一般建筑热损失主要通过传输、渗透/渗出和通风发生（图3）。屋顶变速器20°F通风管渗漏门窗盛行风渗透70°F C2701图3。建筑物的热量损失。建筑物所需的加热能力取决于设计温度、使用的室外空气量和居住者的体力活动。盛行风影响热损失率和渗透程度。加热系统的尺寸必须能够在建筑物可能经历的冷室外温度（室外设计温度）下加热建筑物。传输是能量通过外表面进入或离开空间的过程。通过从室内温度中减去室外温度并将结果乘以表面材料的传热系数，计算能量传输速率。传输速率随外表面的厚度和结构而变化，但对所有外表面的计算方式相同：单位面积和单位时间的能量传输=（TIN-TOUT）x HTC，其中：TIN=室内温度TOUT=室外温度HTC=传热系数=Btu单位时间x单位面积x单位温度

GENERAL Building heat loss occurs mainly through transmission, infiltration/exfiltration, and ventilation (Fig. 3). ROOF TRANSMISSION 20°F VENTILATION DUCT EXFILTRATION DOOR WINDOW PREVAILING WINDS INFILTRATION 70°F C2701 Fig. 3. Heat Loss from a Building. The heating capacity required for a building depends on the design temperature, the quantity of outdoor air used, and the physical activity of the occupants. Prevailing winds affect the rate of heat loss and the degree of infiltration. The heating system must be sized to heat the building at the coldest outdoor temperature the building is likely to experience (outdoor design temperature). Transmission is the process by which energy enters or leaves a space through exterior surfaces. The rate of energy transmission is calculated by subtracting the outdoor temperature from the indoor temperature and multiplying the result by the heat transfer coefficient of the surface materials. The rate of transmission varies with the thickness and construction of the exterior surfaces but is calculated the same way for all exterior surfaces: Energy Transmission per Unit Area and Unit Time = (TIN - TOUT) x HTC Where: TIN = indoor temperature TOUT = outdoor temperature HTC = heat transfer coefficient = Btu Unit Time x Unit Area x Unit Temperatur