本研究分析壓力比、間隙、齒距、齒厚及齒長分別對迷宮式軸封性能的影響。利用CFD軟體ANSYS FLUENT對迷宮式軸封內流場進行模擬計算，Navier-Stokes方程式是應用有限體積法配合紊流模型來求解，本文選擇使用k-ε紊流模型，由計算所得之排放係數、速度、壓力及壓降與不同軸封參數進行比較。數值分析結果顯示壓力比及間隙為主要影響軸封性能的參數，其次為齒距及齒厚，齒長幾乎不影響，並且越小的壓力比及間隙、越大的齒距及齒厚，其軸封密封能力會越好。

This study analyzed the effects of pressure ratio, clearance, tooth pitch, tooth thickness and tooth height on the performance of labyrinth seals. The CFD software ANSYS FLUENT is used to predict the flow field in the labyrinth seal. Navier-Stokes equations are solved using finite volume method by employing turbulence model. This study used k-ε turbulence model. The discharge coefficient, velocity, pressure and pressure drop obtained from the calculation are compared with different seal parameters. Numerical analysis results show that the pressure ratio and clearance are the main parameters that affect the performance of the seal, followed by the tooth pitch and tooth thickness, and the tooth height has almost no effect. Finally, the seal leakage performance becomes better as pressure ratio and clearance decrease and as tooth pitch and tooth thickness increase.

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