超高中庭烟气自然充填的数值模拟分析

Numerical simulation of smoke natural filling in super-high atriums

基于Tanaka的普通中庭全尺寸热烟实验结果,采用FDS软件进行了中庭数值模拟边界条件的验证研究。基于验证后的中庭数值模型,扩展为3个超高中庭,研究了横截面面积相同、高度不同的超高中庭的烟羽流充填现象。结果表明:采用数值模拟方法预测中庭烟层高度可行;数值模拟结果与实验结果之间存在一定误差,但烟层下降的趋势一致;超高中庭横截面面积相同、高度不同时,触顶前烟羽流自由上升过程的形态一致,中庭的烟气充填方式与中庭高度有关,较低的中庭烟气主要为沉降式充填方式(先触顶、后沉降),较高的中庭烟气主要为竖直蔓延式充填方式(先触壁、再填充、最后触顶)。

Based on the results of full-scale hot smoke experiment by Tanaka in common atrium, verifies the boundary conditions of numerical simulation of atrium by FDS software. Applies three superhigh atrium models based on the verified atrium numerical model, and studies the filling of the plume flow in the atriums with same cross-section area and different heights. The results show that the numerical simulation method is feasible to predict the height of the smoke layer in the atrium. There is a certain error between the numerical simulation results and the experimental results, but the downward trend of the smoke layer is consistent. With the same cross-section area of the super-high atriums and the different height, the shape of the free rising process of the smoke plume before the touching top is consistent. The smoke filling mode of the atrium is related to the height of the atrium. The filling of lower atrium smoke is mainly in descending mode (firstly touching the top and then settling), and the higher atrium smoke is mainly in spread up filling mode (firstly touching the wall and then filling, finally touching the top).