氫氣是一種極具潛力的無碳內燃機燃料。然而，其高度反應性帶來了與異常燃燒及爆震相關的挑戰，因此界定安全操作界限顯得至關重要。本研究在嚴格控制的熱力學條件下，利用定容燃燒室（Constant Volume Combustion Chamber, CVCC）探討氫氣燃燒之緩燃與爆震特性。實驗在初始壓力為 4、6 及 8 bar，初始溫度為 423、473 及 523 K，以及當量比（ER）為 0.6、0.8 及 1.0 的條件下進行。由燃燒室內壓力歷程中推導點火延遲（ID）、CA50 與燃燒持續時間（BDUR），並進一步用以估算有效火焰傳播速度，以辨識燃燒型態於不同熱力學條件下的轉換。結果顯示，燃燒行為由稀薄條件 ER = 0.6 下之緩慢且穩定的緩燃，隨當量比提升至 ER = 0.8–1.0，轉變為高度反應性且近似爆震的燃燒行為，其特徵包括劇烈的壓力上升、高熱釋放量，以及接近或超過當地音速的火焰傳播速度，而初始壓力與溫度的增加進一步強化上述效應。隨後，將由 CVCC 所獲得的燃燒特性應用於氫氣引擎實驗平台，並以指示平均有效壓力變異係數（CoV IMEP）評估燃燒穩定性。引擎實驗結果顯示，稀薄燃燒操作（λ ≥ 1.6）可提供穩定且可重複的燃燒行為，而較濃的操作條件則呈現明顯的不穩定性與爆震傾向。整體而言，本研究建立了 CVCC 基礎燃燒行為與實際氫氣引擎安全操作界限之間的直接關聯，並為氫氣引擎之穩定與安全運轉提供指引。

Hydrogen is a promising carbon free fuel for internal combustion engines. However, its high reactivity poses challenges related to abnormal combustion and detonation, making the identification of safe operating limits essential. This study investigates the deflagration and detonation characteristics of hydrogen combustion using a constant volume combustion chamber (CVCC) under well controlled thermodynamic conditions. Experiments were conducted at initial pressures of 4, 6, and 8bar, initial temperatures of 423, 473, and 523K, and equivalence ratios (ER) of 0.6, 0.8, and 1.0. Ignition delay (ID), CA50, and burn duration (BDUR) were derived from in-chamber pressure histories and used to estimate effective flame propagation speed, enabling identification of combustion regime transitions. The results show a clear progression from slow, stable deflagration at lean conditions ER = 0.6 to highly reactive, detonation behavior at ER = 0.8-1.0, characterized by sharp pressure rise, elevated heat release, and flame speeds approaching or exceeding the local sound speed, with increasing pressure and temperature further intensifying these effects. The CVCC derived combustion characteristics were subsequently applied to a hydrogen engine experimental platform, where combustion stability was evaluated using the coefficient of variation of indicated mean effective pressure (CoV IMEP). Engine results indicate that lean operation (λ ≥ 1.6) provides stable and repeatable combustion, while richer conditions exhibit pronounced instability and detonation prone behavior. Overall, this study establishes a direct link between fundamental CVCC combustion behavior and practical hydrogen engine safety limits, providing guidance for stable and safe hydrogen engine operation.

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