本研究旨在透過仿生魚鱗結構控制壓縮機葉柵中的角分離及渦可視化的流場現象，從而提升性能和穩定性。由於壓縮機葉片吸力面與端壁交界處的角分離仍是氣動效率降低的主要原因，其導致通道堵塞、全壓損失增加及穩定性下降。為應對此挑戰，本研究提出受生物魚鱗幾何排列啟發的被動流動控制策略。魚鱗狀表面結構被應用於葉片吸力面以減少黏性阻力並控制二次流行為。通過風洞實驗與數值模擬評估壓縮機氣動效應。為評估其效果，我們使用二維投影流線、軸向速度密度（AVD）和渦可視化技術分析二次流結構。結果表明，仿生魚鱗構型誘導爬升渦，為端壁附近的低動量流體提供能量，有效抑制通道渦與角渦。這促使展向穿透深度減少，全壓損失降低高達5.69%，低能流體體積減少18.36%。此外，AVD等值面在識別低能流體區域方面具有關鍵作用，這些區域與全壓損失分佈密切相關。仿生結構對二次流的增強控制也有助於改善端壁區域的流動均勻性。這些發現顯示了仿生啟發設計在渦輪機械系統中抑制角渦與提升氣動效率的潛力。此外，該設計在效能表現與可製造性方面的優勢，且在實際應用於航太壓縮機上具有可行性，特別適用於追求高效率、穩定性與製造簡易性的工程需求。

This study investigates controlling corner separation and visualizing flow field phenomena in compressor cascades using a bio-inspired fish scale structure, thereby enhancing performance and stability. Corner separation at the junction of the compressor blade suction surface and end-wall remains a primary cause of aerodynamic inefficiency, leading to passage blockage, increased total pressure loss, and reduced stability. To address this challenge, this study proposes a passive flow control strategy inspired by the geometric arrangement of biological fish scales. A fish scale-like surface structure is applied to the blade suction surface to reduce viscous drag and modulate secondary flow behavior. Wind tunnel experiments and numerical simulations evaluated compressor aerodynamic effects. To assess its effects, secondary flow structures were analyzed using 2D projected streamlines, axial velocity density (AVD), and vortex visualization technique. The results indicate that the bio-inspired scale structure induces climbing vortices that shrink low-energy fluid region near the end-wall, effectively suppressing both passage and corner vortices. This leads a decreased the spanwise penetration depth, a reduction total pressure loss by up to 5.69%, and an 18.36% decrease in the volume of low-energy fluid. Additionally, the AVD iso-surface serves as a critical tool for identifying low-energy fluid regions that exhibit a strong correlation with the distribution of total pressure loss. Moreover, the biomimetic structure’s enhanced regulation of secondary flows contributes significantly to the improved uniformity of flow in the end-wall region. These findings highlight the potential of biologically inspired designs for corner vortex suppression and aerodynamic efficiency improvement in turbomachinery systems. Furthermore, the demonstrated effectiveness and manufacturability of the proposed design suggest promising opportunities for practical implementation in aero-engine compressors where efficiency, stability, and ease of fabrication are essential.

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