Abstract Evaluation of the thermal comfort is essential for complex ventilation systems design. Assessment of thermal indices requires representative velocity and pressure fields' values. When simulating the air flow in large facilities such as stadium, the effect of crowds' geometrical features needs to be captured. Using porous models approximations to simulate the aerodynamic effect of detailed spectators' geometry reduces the required mesh size and associated processing time. This paper investigates the use of different porous media models approximations for capturing the effect of large crowds inside complex building systems, such as stadiums. Their efficiency of capturing the effect of spectators on the air flow were compared to the simulation of the exact spectators' geometry. The exact spectators' geometrical model was of a stadium tiers section with 28 spectators. Using a wind tunnel, the exact spectator's model results were validated against a 1:10 scaled physical model. The experiments included PIV and hot-wire velocity measurements. The results of the pressure drop were used to obtain the coefficients needed to utilize the porous models. Compared to the exact spectators' case, the three-dimensional porous volume model approximation yielded an average absolute error of 24.5% in velocity, while the two-dimensional porous jump model yielded results with an average error of 1.5%. In comparison to the exact model cooling load, the results yielded a difference of 6% for the 2D porous jump and 6.5% for the 3D porous volume. Nevertheless, both models yielded more representative results than the case of simulation of empty bleachers.

中文翻译：

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使用多孔模型近似模拟观众的气动阻力

摘要 热舒适性评估对于复杂的通风系统设计至关重要。热指数的评估需要具有代表性的速度和压力场值。在模拟体育场等大型设施中的气流时，需要捕捉人群几何特征的影响。使用多孔模型近似值来模拟详细观众几何形状的空气动力学效果可减少所需的网格尺寸和相关的处理时间。本文研究了使用不同的多孔介质模型近似来捕捉复杂建筑系统（如体育场）内大量人群的影响。它们捕捉观众对气流影响的效率与精确观众几何形状的模拟进行了比较。准确的观众 几何模型是一个有 28 名观众的体育场层部分。使用风洞，准确的旁观者模型结果与 1:10 比例的物理模型进行了验证。实验包括 PIV 和热线速度测量。压降的结果用于获得利用多孔模型所需的系数。与确切的旁观者情况相比，三维多孔体积模型近似产生了 24.5% 的速度平均绝对误差，而二维多孔跳跃模型产生的结果平均误差为 1.5%。与精确的模型冷却负载相比，结果产生了 2D 多孔跳跃的 6% 和 3D 多孔体积的 6.5% 的差异。尽管如此，这两种模型都比模拟空看台的情况产生了更具代表性的结果。