基于CFD模型的双膜大跨度拱棚热环境模拟

Thermal environment simulation in a double‐film large‐span greenhouse based on CFD model

为探明多层覆盖对大跨度拱棚典型季节热性能的影响,采用计算流体力学(CFD)方法构建双膜大跨度拱棚模型,探究夏季无风和冬季有风2种较为极端环境下拱棚内热环境的分布规律,并与单膜大跨度拱棚进行对比。结果表明:拱棚内温度模拟值与实测值的平均相对误差为1.53%,均方根误差0.75℃,构建的CFD模型可准确模拟双膜大跨度拱棚内的温度分布;夏季工况下双膜大跨度拱棚在缓冲区域会产生高温积聚,导致双膜大跨度拱棚平均温度比单膜大跨度拱棚高约1℃;冬季工况下双膜大跨度拱棚内外层空间温差较大,双膜大跨度拱棚平均温度比单膜大跨度拱棚高5.1~10.6℃。综上,双膜大跨度拱棚更适用于寿光地区的气候环境。

To investigate the influence of multi-layer coverage on the typical seasonal thermal performance of large-span greenhouse,a double-film large-span greenhouse model was constructed based on computational fluid dynamics(CFD)model.The distribution law of the internal heat environment in the greenhouse under two extreme environments of no wind in summer and wind in winter was investigated and were then compared and analyzed with the thermal environment distribution of a single-film greenhouse.The results show that:The constructed CFD model accurately represents the temperature distribution inside the double-film large-span greenhouse,with an average relative error of 1.53%and a root mean square error of 0.75.During summer conditions,the double-film large-span greenhouse shows higher temperature accumulation in the buffer area,leading to an average temperature of about 1°C higher than that of the single-film greenhouse.Moreover,during winter conditions,the double-film large-span greenhouse achieves a larger winter difference inside and outside,with an average temperature 5.1°C to 10.6°C higher than that of the single-film greenhouse.To sum up,the double-film large-span greenhouse is more suitable for the climatic environment of the Shouguang area.