# CFD 코드의 기포류 유동 예측을 위한 기포크기모델 평가

Bak, Jin-yeong;Yun, Byong-jo
박진영;윤병조

• Accepted : 2016.01.29
• Published : 2016.03.31
• 22 4

#### Abstract

Bubble size is a key parameter for an accurate prediction of bubble behaviours in the multi-dimensional two-phase flow. In the current STAR CCM+ CFD code, a mechanistic bubble size model $S{\gamma}$ is available for the prediction of bubble size in the flow channel. As another model, Yun model is developed based on DEBORA that is subcooled boiling data in high pressure. In this study, numerical simulation for the gas-liquid two-phase flow was conducted to validate and confirm the performance of $S{\gamma}$ model and Yun model, using the commercial CFD code STAR CCM+ ver. 10.02. For this, local bubble models was evaluated against the air-water data from DEDALE experiments (1995) and Hibiki et al. (2001) in the vertical pipe. All numerical results of $S{\gamma}$ model predicted reasonably the two-phase flow parameters and Yun model is needed to be improved for the prediction of air-water flow under low pressure condition.

#### Keywords

two-phase flow;air-water flow;bubbly flow;bubble size model

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#### Acknowledgement

Grant : BK21플러스

Supported by : 부산대학교