本研究旨在探討高壓水刀除銹系統中，扇形噴嘴之間的流場干擾對衝擊力分佈的影響，並優化噴嘴間距、轉位角、前傾角與工作高度等參數，以提升鋼板表面除銹均勻性與系統效能，並降低實驗成本。參考中鋼提供之噴嘴型號與操作條件，使用 SolidWorks 建立三維幾何模型，並運用 OpenFOAM 建構三維兩相流模擬系統。模擬採用Volume of Fluid（VOF）模型處理氣液界面，結合Large Eddy Simulation（LES）紊流模型解析射流內部不穩定結構，並搭配 Adaptive Mesh Refinement（AMR）技術，根據體積分率與界面梯度動態加密網格，以兼顧整體流場與細部破裂行為。邊界條件設定入口質量流率為 1.392 kg/s，對應實際流量 83.5 L/min 與操作壓力340 bar。模擬結果有助於釐清破裂與衝擊特徵，提供除銹系統參數設計之理論依據。
模擬結果顯示，工作高度顯著影響液膜破裂行為與衝擊型態，當高度過低時水刀仍具連續性，能以完整射流形式衝擊基板，產生較高而集中的衝擊壓力，隨高度增加，流體因界面不穩定性破裂為液滴狀，導致壓力衰減與分佈不集中。在多噴嘴配置中，前傾角0度與轉位角0度可有效提升重疊區域壓力均勻性，並抑制沖蝕區（washout zone）的形成。整體而言，本研究所建立之高解析模擬可捕捉水刀破裂與壓力分佈細節，然而實際除銹行為仍須透過沖蝕實驗進行驗證。
整體而言，本研究所建立之高解析數值模擬模型，成功捕捉水刀破裂與衝擊壓力空間分佈細節，為未來進一步探討除銹效率、熱衝擊影響與實體試驗驗證提供理論基礎與參數設計依據。未來可整合金屬表面應力分析、熱傳行為與材料剝離機制進行跨尺度耦合模擬，進一步精準預測實際除銹行為。

This study investigates the effect of flow interference between fan-shaped nozzles in a high-pressure water jet descaling system. The objective is to optimize nozzle spacing, rotational angle, inclination angle, and standoff height to improve rust removal uniformity and system performance while reducing experimental cost. Based on operational parameters provided by China Steel Corporation, a 3D two-phase numerical model was developed using OpenFOAM. The simulation employs the Volume of Fluid (VOF) method to track the air–water interface, coupled with the Large Eddy Simulation (LES) turbulence model to resolve jet instability, and Adaptive Mesh Refinement (AMR) for local mesh refinement near the interface. At a mass flow rate of 1.392 kg/s and 340 bar pressure, the results show that standoff height significantly affects jet breakup and impact behavior. A short height maintains jet coherence and pressure intensity, whereas longer distances result in droplet breakup and dispersed impact. A 0° inclination and rotation angle improve pressure uniformity in the overlap region and suppress washout formation. This high-resolution model provides a theoretical foundation for future analysis of descaling efficiency, thermal shock effects, and material detachment mechanisms.

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