论文部分内容阅读
居住性民用建筑室内温度一般在14～18℃范围内,相对湿度约50％～70％。设计规范考虑了卫生要求、经济技术因素规定在冬季建筑围护物采暖耗热量计算或其他有关计算中,建筑内表面换热系数采用α_n=7.5千卡/小时·米~2·度。相应地规定建筑内表面温度允许低于室内空气温度4～6℃,对于相对温度较大的房间,通常规定建筑内表面温度不低于室内空气露点温度。 现代猪舍建筑由于使用功能不同,舍内环境条件与居住性民用建筑有显著的差异。肥猪集约饲养,猪体表面与建筑内灰面之间具有强烈的辐射热交换,导致猪舍建筑内表面温度接近于舍内空气温度;其次,在猪舍实际使用过程中,肥猪还散发大量水分。舍内相对湿度偏高也要求建筑内表面温度不低于舍内空气露点温度。居住性民用建筑内表面换热系数α_n=7.5千卡/小时·米~2·度,不适用于猪舍建筑。 本文在如下条件之下以北京地区为例,对采暖的和非采暖的双列式育肥猪舍建筑内表面换热系数α_n进行核算: 1.猪舍建筑内表面温度低于舍内空气1℃。 2.认为猪群的体表面积大约有一半参与和屋顶、外墙内表面之间的辐射热交换。 3.运用与猪舍内辐射等价的平行六面体封闭系统并划出肥猪控制区来求解辐射角系数ψ_(i-l)。 计算过程中还考虑了猪舍内二氧化碳,水蒸汽吸收辐射热能的影响
Residential building civil indoor temperature is generally in the range of 14 ~ 18 ℃, relative humidity of about 50% to 70%. Design specifications take health requirements into consideration. Economic and technical factors stipulate that the heat transfer coefficient of the building’s internal surface should be α_n = 7.5 kcal / hm -2 · ° C in the calculation of heating energy consumption of building envelope during winter or other relevant calculation. Correspondingly, it is stipulated that the temperature inside the building should be lower than the indoor air temperature by 4 ~ 6 ℃. For the room with relatively large temperature, the inner surface temperature of the building is usually stipulated not to be lower than the dew point of the indoor air. Modern pigsty buildings due to the use of different functions, the environment within the homes and residential buildings have significant differences. Intensive pig raising, the pig body surface and the gray surface of the building has a strong radiation heat exchange, resulting in pig building interior surface temperature close to the air temperature inside the house; Second, the pig in the actual use of the process, the pig is also distributed A lot of water. High relative humidity inside the building also requires that the building surface temperature not lower than the dehumidification air temperature. Residential building heat exchange coefficient α_n = 7.5 kcal / h · m ~ 2 · degrees, not suitable for pig building. In this paper, under the following conditions in Beijing as an example, heating and non-heating double row fattening pig building heat exchanger coefficient α_n accounting: 1 building interior surface temperature is lower than 1 ℃ . 2. Consider that about half of the herd’s surface area is involved in the radiative heat exchange between the roof and the inner surface of the façade. 3. Solve the radiation angle coefficient ψ_ (i-1) by using the radiation-equivalent parallelepiped closed system in the pig house and draw the control area of the pig. The calculation also takes into account the carbon dioxide in the pig house, water vapor to absorb the impact of radiant heat