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Understanding the behavior of subsonic, sonic, and supersonic methane jet flames is crucial for safety engineering, especially in the gas industry.Knowledge and assessment of jet flame dynamics, particularly regarding stability and blow-out in various incident scenarios, can equip engineers with engineering solutions on prevention and mitigation.A Computational Fluid Dynamics model was developed and applied to reproduce the experimentally determined critical diameter and flame stability limits for methane non-premixed flames.The critical diameter denotes the minimum nozzle diameter size at which a flame remains stable at all driving pressures.Sustained flames exist for diameters equal to or larger than the critical diameter while diameters less than critical exhibit two pressure limits for sustained flames.At lower pressures, the flame is initially attached, but as pressure increases, it becomes lifted, leading to blow-out.Then, with significant increase of the storage pressure above the upper pressure limit, the sustained flame restabilizes.The blow-out zone spans the pressure range between the lower and upper pressure limits, shaping the stability curve of the flame.Blow-out and stable flame behavior in the region of the key points defining a flame stability curve are simulated here and compared to experiments, specifically the critical diameter and the two limits (points to the furthest left side of the curve).The realizable k- turbulence model, along with the Eddy Dissipation Concept for combustion and Discrete Ordinates model for radiation were employed.The critical diameter was predicted as 42 mm which aligns with that measured experimentally by McCaffrey and Evans (1988).The limits of the stability curve are predicted here numerically for the first time.The numerically predicted stability curve is in close agreement with the experimental study (McCaffrey and Evans, 1988).The validated model is shown to accurately predict methane flame behavior.