环形通风口参数对圆形煤仓气体和粉尘运移的影响

摘 要：根据通风安全理论与基于组分输运模型的CFD方法，探讨圆形煤仓通风安全特性及合适的性能评价指标。以100 m直径圆形煤仓为例，研究环形通风口开口方式、位置及几何尺寸等因素对煤粉尘和气体分布和运移特性及去除效率的影响规律，得到最优的通风口设计参数。研究结果表明：单环形开口情况下，通风口由水平改为侧向，可改善内部环境，提高煤粉尘和有害气体的去除效率，推荐侧向环形通风口高度为2 m；在穹顶中部增设环形开口，能够有效减少煤仓上方30~35 m高度处的悬浮污染物量；双环形开口最优位置分别为15，31 m，可使煤仓内部大部分区域粉尘质量浓度低于10 mg/m3，CO2气体质量浓度低于30 mg/m3；排污效率最高均接近80%。研究成果可为超大空间圆形煤仓通风安全设计提供参考。

Influence of annular opening parameters on harmful gas and dust migration in large space circular coal storage dome

Abstract: Simulation models were developed for an aircraft fire extinguishing system using Amesim software. The influence of the parameters such as the filling pressure, the temperature of the fire extinguishing agent, the roughness of the pipe, the diameter of the nozzle, and the diameter of the branch pipe of the pipeline were studied. It is found that under the filling mass of 5.34 kg of fire-extinguishing agent, the spray mass curves of fire-extinguishing agent under the filling pressure of 4, 5, and 6 MPa are similar. The lower the temperature of the extinguishing agent, the slower the spray rate. The spray time of -50 ℃ fire extinguishing agent is about 2.5 times that of -10 ℃. Roughness also has a significant effect on the amount of fire extinguishing agent sprayed. The lower the roughness, the faster the spray amount. The quality curve of fire extinguishing agent under the roughness of 0.13 mm and 0.20 mm is similar. The nozzle diameters of 16 mm, 17 mm and 18 mm have little effect on the overall fire extinguishing agent spray quality of the system, but the flow distribution between the nozzles will be affected by the change of the nozzle diameter. When the diameter combination of the long branch pipe connecting 3 nozzles and the short branch pipe connecting 2 nozzles is (16, 14 mm) and (20, 12 mm), the ratio of the amount of fire extinguishing agent sprayed from the two branch pipes is close to 1.