基於飛行安全之重要性，機翼積冰是適航審定中一複雜過程，需要高效率且精密度及精確度高的工具。目前電腦計算能力提供之可能性日益漸增，本文將探討機翼上三維積冰之熱力學平衡模型發展。
本文使用之CFD軟體為OpenFoam C++ toolbox，並成功建立一新求解器-icingFoam，此求解器源自於rhoPimpleFoam。利用典型的RANS PIMPLE algorithm求解空氣流場，此演算法可應用於可壓縮流之各種現代化紊流模型計算。本文使用Eulerian建立一可觀察液滴流動之求解器，並在二維及三維情況下，進行測試和驗證。模擬結果顯示與實驗結果具有良好的一致性。此外，OpenFOAM之網格變形應用，可用於探討模擬積冰過程。
由於網格品質因素，模擬結果雖無法與文獻中七分鐘後之積冰結果做比較。但積冰過程所獲得之訊息，是值得令人探討的。在未來，或許可使用更先進的網格變形工具來克服問題。最後觀察獲得以下結果，以熱力學平衡模型為基礎進行測試及應用於Messinger model；本研究對於傳統的smooth wall functions無法適用於準確預測對流之熱通量，故必須採用rough wall function；由於需模擬固體昇華之影響，建立之新模型，將不使用heat transfer coefficient；對於熱通量而言，停滯點之外的區域，由於無缺乏物理意義，結果非令人滿意，但在停滯點上與預期相符。
結論，本研究建立完整的open source finite volume求解器及積冰模型。此研究項目，在未來上仍有許多地方需改進和探討，本文已完成此模擬之基礎之建立，可供日後發展模擬積冰之依據。

Fundamental to the safety of an aircraft, the icing certification is a complex process that requires efficient and accurate tools. The growing computer power offers increasingly possibilities and so the current work aims to set up the bases of a thermodynamic equilibrium finite volume rime ice accretion model.
The OpenFoam C++ toolbox has been successfully used to create a new solver, icingFoam, that is derived from the existing air solver rhoPimpleFoam. The air flow is calculated through a typical RANS PIMPLE algorithm that is able to handle compressible flow with various modern turbulence models. A custom Eulerian droplet motion solver has then been implemented and validated on both 2D and 3D cases with good agreement with experiments. Next, the mesh morphing abilities of OpenFoam have been used to simulate the ice growth. Although it has not been possible to reach the seven minutes of icing required by the validation case due to the mesh quality degradation, the results are encouraging. Indeed, this problem might be overcome in the future by the use of more advanced morphing tools. Finally, a rime ice thermodynamic equilibrium model based on Messinger model has been implemented and tested. The use of a rough wall function soon appeared to be a necessity as the traditional smooth wall functions are unable to predict accurately the convective heat flux. In order to simulate the sublimation effect, an alternative model that doesn’t use the heat transfer coefficient is proposed in this work.
Concluding, this work led to the establishment of a fully functional open source finite volume solver able to simulate the rime ice accretion process. Even though many improvements are still to be done, all the fundamental bricks are set up and ready to use.

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