Effects of Relative Position between a Stator and a Rotor on Steam Condensing Flow in Rotating Machinery

다국어 초록 (Multilingual Abstract)

Flow of steam is different from other gas flows and involves droplet generation in the flow field. This phase-transition affects not only flow aspects, but also machine performance in a negative way. These days, CFD is widely used in machine design and optimization processes, so phase-transition phenomena in steam flows should be considered in CFD to predict the internal flows precisely. In the past, non-equilibrium wet-steam model was implemented on in house code T-Flow and it was applied to steady calculations of a steam turbine model with changing stator/rotor interface. The results showed that mixing plane method is not appropriate to simulate steam condensing flow and frozen rotor method can be affected by relative position between a stator and a rotor. Therefore, steady wet-steam flows with non-equilibrium phase-transition were simulated for a steam turbine model in this study with 4 different stator-rotor positions and their effects on the wet-steam flow fields were investigated in detail.

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