基于射流扩散特性分析的静压箱结构参数优化研究*
摘要：
运用数值计算与实验验证相结合的方法,基于射流扩散特性分析,对防排烟及通风空调系统用静压箱结构参数进行了优化研究,分析了静压箱迎风面宽高比W/H 和箱体长度L 对流动与阻力分布特性的影响。研究表明,W/H 应根据气流受限度m 值不同分段设计,在0<<span class="emphasis_italic">m
Abstract：
Using a method combining numerical calculation and experimental verification, based on the analysis of jet diffusion characteristics, the structural parameters of plenum chambers for smoke control and ventilation and air conditioning systems are optimized. The influences of the width to height ratio (W/H) of the plenum chamber on the windward side and the chamber length (L) on the flow and resistance distribution characteristics are analysed.The research shows that W/H should be designed in stages according to different airflow confinement (m) values.Under the conditions of 0<m≤0.3 and 0.3<m≤0.6, W/H should be designed as 1 and 5, respectively. The jet expansion angle formula is used to judge the degree of airflow confinement in the chamber, and the optimal value of the chamber length is determined to be the greatest of 3.0-4.0 times the equivalent diameter of the windward surface of the plenum chamber, the critical restricted length of the horizontal jet and the critical restricted length of the vertical jet along the chamber, and the structural design method of a single channel plenum chamber is obtained.
Keywords:plenum chamber; jet diffusion; flow resistance characteristic; structural design; parameter optimization; width to height ratio; chamber length