本研究針對迴轉式壓縮機中的油分離器設計進行深入探討，旨在簡化油分離器外型設計減少裝配程序降低作業錯誤率並保持油分離效率。冷凍油在壓縮機運行中發揮潤滑、冷卻等作用，但部分油隨冷媒進入系統會降低整體性能，特別是影響蒸發器的效率。
為此，本研究採用CFD-DEM數值模擬方法結合實驗測試，探討不同結構設計的油分離器對壓縮機性能的影響。模擬與實驗數據顯示，旋轉式油分離器經優化後能有效提升油滴分離效率，尤其是在冷媒氣流經過排出口前。通過對比形式C1、C3、C4的端板油分離器設計，發現優化引出口截面積及氣流方向的設計能顯著減少油滴排出，提升系統能源效率比（EER）。實驗進一步證實，這些設計方案在不顯著增加系統壓降的情況下，實現了油循環率的顯著降低。本研究為迴轉式壓縮機的油循環問題提供了可行的設計優化方案，並為未來相關系統的節能設計提供了參考依據。

This study focuses on the design optimization of the oil separator in rotary compressors, aiming to simplify the external structure, reduce assembly procedures, minimize operational errors, and maintain effective oil separation efficiency. Refrigerant oil plays essential roles such as lubrication and cooling during compressor operation. However, a portion of the oil inevitably flows with the refrigerant into the system, which can degrade overall system performance—particularly the efficiency of the evaporator.
To address this issue, a combination of CFD-DEM numerical simulation and experimental testing was employed to investigate the impact of various oil separator structural designs on compressor performance. Both simulation and experimental results reveal that an optimized rotating-type oil separator can effectively enhance the separation efficiency of oil droplets, especially before the refrigerant exits through the discharge outlet. By comparing three end-plate oil separator configurations (C1, C3, and C4), it was found that designs featuring optimized discharge outlet area and flow direction significantly reduce oil droplet discharge and improve the system’s Energy Efficiency Ratio (EER). Further experimental validation confirms that these optimized designs achieve a notable reduction in oil circulation rate without substantially increasing system pressure drop.
This research presents a practical design optimization approach for managing oil circulation in rotary compressors and provides valuable references for future energy-saving designs in related refrigeration and air-conditioning systems.

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