课件：第四章空调间.pptVIP

因此： 正确、科学、合理的使用空调 适当增加户外活动和体育锻炼 合理膳食、劳逸结合 特殊人群尽量少吹空调，多吹自然风，保持良好的生活方式 在充分享受空调给我们带来的凉爽舒适和快乐的同时避免空调病的入侵 后面内容直接删除就行 资料可以编辑修改使用 资料可以编辑修改使用 资料仅供参考，实际情况实际分析 The total refrigeration load, in terms of Btu per hour, is then calculated using the following formula, where the supply airflow is expressed in cfm, h1 is the entering-air enthalpy in Btu/lb, and h2 is the leaving-air enthalpy in Btu/lb. Realize that 4.5 is not a constant! It is the product of density of air and the conversion factor of 60 minutes per hour. The density of air at “standard” conditions (69.5°F DB dry air at sea level) results in the value 4.5. Air at other conditions and elevations will cause this factor to change. Density = 0.075 lb/cu ft 0.075 x 60 min/hr = 4.5 The space cooling load is the rate at which heat must be removed from a space in order to maintain the desired conditions in the space, generally a dry-bulb temperature and relative humidity. The cooling load for a space can be made up of many components, including: Conduction heat gain from outdoors through the roof, exterior walls, skylights, and windows. (This includes the effects of the sun shining on these exterior surfaces.) Solar radiation heat gain through skylights and windows. Conduction heat gain from adjoining spaces through the ceiling, interior partition walls, and floor. Internal heat gains due to people, lights, appliances, and equipment in the space. Heat gain due to hot, humid air infiltrating into the space from outdoors through doors, windows, and small cracks in the building envelope. In addition, the cooling coil in the building HVAC system has to handle other components of the total building cooling load, including: Heat gain due to outdoor air deliberately brought into the building for ventilation purposes. Heat generated by the fans in the system and possibly other heat gains in the system. Throughout this period, we will assume that the space has no plenum (the space between the ceiling and roof). Therefo