加压送风系统关闭风口漏风量计算的方法

Closed air outlet leakage calculation method for pressurization air supply system

根据流体力学的理论,建立了加压送风系统关闭风口漏风量的数学计算模型,并建立了关闭风口两侧静压差、各管段沿程阻力、静压复得量等6项中间参数的子项模型。以优化防烟方案为物理模型,按是否考虑静压复得、采用不同等级气密性风口、改变主风道断面积等条件,组合成5类范例,并进行了数值计算。结果表明:附加系数法和直接导用气密性标准的计算方法都有明显缺陷;当风口的气密性标准较高时,可采用忽略静压复得量的简化算法。

According to the fluid mechanics theory,establishes the leakage calculation mathematical model and six sub-models including the static pressure difference across the closed air outlet,the frictional resistance of each duct sections,the static pressure regain etc.Taking the optimizing smoke control scheme as the physical model,sums up five type of examples according to whether taking the static pressure regain into consideration,the outlets with different air tightness grades,and the main duct with different cross-section areas.The results from a numerical calculation made by the author indicate that the additional coefficient method and the method directly based on the air tightness standard have remarkable defects;the simplified calculation method is applicable to the outlets with higher air tightness grade.