本研究針對Gamma型史特靈引擎中移動再生器之孔洞幾何參數進行分析，探討孔洞面積比與孔洞數量對引擎性能之影響。由於Gamma型史特靈引擎之動力活塞與移氣器分別配置於不同汽缸內，工作流體在冷熱端之間的往復流動會受到移動再生器運動及其孔洞配置影響，因此移動再生器之孔洞設計將改變工作流體通過再生器時之流速分布、噴流型態與熱交換行為，進而影響引擎之輸出淨功率、再生器有效度與熱效率。
本研究使用計算流體力學（Computational Fluid Dynamics, CFD）建立Gamma型史特靈引擎之三維暫態數值模型，並模擬動力活塞與移動再生器於週期性運轉下之流場與熱傳行為。為比較不同幾何配置之影響，本研究採用參數分析法，選定兩項控制因子，分別為移動再生器單一板面之孔洞總面積與該板總面積之比值，以及移動再生器孔洞數量。其中，孔洞面積比設定為14%、17%、20%與23%，孔洞數量設定為15、30、50、75與105個，共建立20組試驗條件，並分別進行CFD模擬分析。
在20組案例中，輸出淨功率與再生器有效度之最佳配置皆為孔洞面積比23%且孔洞數量50個，其最大輸出淨功率為69.86 W，最高再生器有效度為62.28%；熱效率之最佳配置則為孔洞面積比23%且孔洞數量15個，其最高熱效率為18.80%。綜合而言，本研究透過CFD模擬結合參數分析法，建立移動再生器孔洞幾何參數之分析流程，其結果可作為後續Gamma型史特靈引擎性能優化與幾何設計之參考。

This numerical study investigates the effects of two geometric parameters of a moving regenerator on the performance of a Gamma-type Stirling engine. Computational fluid dynamics (CFD) was used to conduct the parametric analysis. The geometric parameters are: the ratio of the total hole area on one moving-regenerator plate to the total area of that plate, and the number of holes on a moving regenerator plate. The hole area ratios were set to 14%, 17%, 20%, and 23%, while the numbers of holes were set to 15, 30, 50, 75, and 105. The four area-ratio levels and five hole-number levels were fully combined, yielding 20 cases. CFD simulations were then performed for each case to calculate the net output power, regenerator effectiveness, and thermal efficiency of the engine.
The simulation results show that the configuration with the hole area ratio of 23% and 50 holes produces the highest net power output within the investigated cases, reaching 69.86 W. The same configuration also yields the highest regenerator effectiveness of 62.28%. For thermal efficiency, the configuration with a hole area ratio of 23% and 15 holes achieves the highest value of 18.80%.
By combining CFD simulations with parametric analysis, this study not only effectively reduces the time and cost required for traditional experimental investigations but also enables a detailed examination of the internal heat transfer mechanisms, flow field structures, and temperature distributions within the engine under different geometric configurations. Furthermore, the effects of these parameters on engine performance, including net output power, regenerator effectiveness, and thermal efficiency, can be systematically analyzed. Therefore, the analysis procedure and results presented in this study provide valuable information for future geometric design and performance optimization of similar Stirling engines.

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