CFD模式應用於防風網特性分析

Effectiveness Analysis of Windbreak Using the CFD Models

陳智霖(Jhih-Lin, Chen) ； 楊素絲(Su-Szu Yang) ； 姚銘輝(Ming-Hwi Yao)

《作物、環境與生物資訊》 14卷1期 (2017/03) Pp. 31-39

https://doi.org/10.30061/CEB.201703_14(1).0004

摘要

農作物生產過程遭受強風吹襲而造成損失，防風網的利用是一種低成本及施作簡易之防災策略。本研究擬建立由計算流體力學(CFD) 評估最適化防風網架設條件，作為提供農作物防風技術之參考依據。試驗結果顯示，試驗田區架設不同網目及高度之防風網，由實測風速變化以驗證CFD 模擬能力，結果顯示CFD模擬值與實際風場通過防風網之減弱趨勢相符，可準確掌握風速流場，做為評估防風網效能之有效工具。另由評估結果，防風網最佳阻風有效長度，水平距離為防風網高度之6 倍，有效高度為防風網高度之1.3 倍。另由實際防風網在颱風期間之阻風效果案例分析，以70%百吉網阻風率可將18m s^(-1) 最大陣風降至4 m s^(-1)，防風效果顯著。

關鍵字

災害 ； 颱風 ； 防風網 ； 計算流體力學

並列摘要

The use of windbreak net is a low-cost and easy-to-use disaster mitigation strategy for crop production. In this study, we set up an evaluation process for the optimum conditions of windbreak net by computational fluid dynamics (CFD) model, which can be used as a reference for crop protection. The results show that CFD simulation can be validated by different mesh size and height of the windbreak net from the experimental area. The results of CFD simulation can be used as an efficient tool to evaluate the effectiveness of the windbreak net, and according to the evaluation results, the effective wind protection length is 6 times the height of the windbreak net, and the effective wind protection height is 1.3 times the height of the windbreak net. In the actual case of a typhoon, the maximum gust of 18 m S^(-1) can be reduced to 4 m S^(-1) by using the windbreak net which caused the 70% blocking rate. The case suggested that wind-proof effect is significant.

並列關鍵字

Disaster ； Typhoon ； Windbreak net ； Computational fluid dynamics (CFD)