熱障塗層系統(TBCs)中氣膜孔冷卻技術在燃氣輪機葉片或是燃燒室的安全設計中起著重要作用，因為氣膜孔冷卻技術有效地降低了頂層周圍的溫度，然而氣膜孔周圍出現應力集中，縮短了使用壽命。因此，本文的目的是利用熱-流-固耦合分析流場、傳熱和熱應力，建立帶氣膜孔冷卻的熱障塗層三維模型，來預測冷卻階段的危險區域，並提供TBCs中冷卻技術的優化設計。溫度分析和應力分析可以通過不同的氣膜冷卻幾何參數和TBCs設計獲得。在本篇研究的前半段主要是在探討氣膜孔冷卻技術的幾何變化並探討美國專利設計優劣。飛機運行過程在高空中會受到火山灰-鈣-鎂-鋁-矽酸CMAS等化學雜質影響，在高溫中會使這些化學物質滲透TBCs。在後半段我們將具有氣膜孔冷卻技術的TBCs加入了CMAS滲透，使得在降溫的過程中發生相變化並探討降溫後的殘留應力。結果顯示傾角30度之氣膜孔為最佳設計，而類梯形孔洞設計確實會帶來良好的溫度與應力分佈。透過CMAS滲透的分析可以得到當滲透的程度越深時所造成的介面應力也越大，由這樣的模擬結果可以提出良好的設計模型建議。

The film cooling technology in thermal barrier coating system (TBCs) plays an important role in the safety design of gas turbine blade or combustion chambers. The film cooling technology effectively reduces the temperature around the top surface. However, larger stress concentration would occur around the cooling hole and then shortens the service life of TBCs. Therefore, this article aims to establish a three-dimensional model of the film cooling thermal barrier coating system to analyze flow field, heat transfer and thermal stress and provide the optimal design of the cooling technology in TBCs. Both temperature and stress distribution are evaluated for different geometric parameters and inclined angles of film cooling system. The residual stresses induced by the phase transformation of CMAS (calcium-magnesium- aluminum-silicate) penetration during the cooling process in the TBCs with film cooling technology are also investigated. The results show that the inclined angle 30°of the film cooling system and the trapezoid-like shaped hole design are shown to be an excellent cooling strategy. It is also found that the interfacial stress between the top coat and bond coat becomes larger when the depth of CMAS penetration is deeper. Based on this simulation result, this article provides the optimal design of film cooling technology of TBCs.

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