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기포 저감 장치의 기포입자 유동특성에 따른 수치해석에 관한 연구

Numerical Study on the Flow Characteristics of Bubble Particles in Bubble Reduction Device

  • 문현식 (공주대학교 일반대학원 기계공학과) ;
  • 유영철 (공주대학교 일반대학원 기계공학과) ;
  • 박성영 (공주대학교 기계자동차공학부)
  • Mun, Hyun-Sik (Mechanical Engineering, Graduate School, Kongju National University) ;
  • Yoo, Young-Cheol (Mechanical Engineering, Graduate School, Kongju National University) ;
  • Park, Sung-Young (Div. of Mechanical & Automotive Engineering, Kongju National University)
  • 투고 : 2020.06.25
  • 심사 : 2020.10.05
  • 발행 : 2020.10.31

초록

기포 저감 장치는 기름의 정량 공급과 관련된 문제 해결의 목적을 둔 장치이다. 따라서 본 연구에서는 기포 저감 장치의 작동 중 기포 입자의 크기별 유동특성을 확인하고자 수치해석을 진행하였다. 기초해석을 진행한 결과, 기포의 상승과 하강이 가장 활발하게 나타나는 영역을 발견하였고, 그 지점을 중심으로 수치적 계산을 수행하였다. 수치적 계산에 앞서 각 변수들 간의 동차성을 확보하기 위하여 무차원 유도를 수행하였다. 무차원 유도를 수행한 데이터를 바탕으로 각 입자의 크기별, 유체의 속도별 25개의 변수 조건을 설정하여 별도의 계산을 통해 기포 상승과 하강의 대한 수식을 도출하였다. 각 변수별로 항력과 부력의 비를 계산하여 기포에 작용하는 항력이 부력보다 큰 경우 기포가 하강하며 기포는 저감되지 않는다고 판단하였고, 부력이 항력보다 큰 경우 기포는 상승하며 기포가 저감된다고 판단하였다. 수치 계산 데이터를 바탕으로 유동 해석을 진행하였다. 유동 해석을 통하여 기포의 상승과 하강을 확인하였고, 수치 계산의 결과와도 일치하는 것을 확인하였다.

Bubble reduction devices are intended to solve problems related to the quantitative supply of oil. Therefore, in this study, numerical analysis was conducted to verify the flow characteristics of bubble particles during the operation of a bubble reduction device. As a result of the basic analysis, the area where the rise and fall of bubbles were most active was found, and numerical calculations were performed focusing on the points. Before the numerical calculations, a non-dimensional derivation was performed to secure homogeneity among the variables. Based on the data obtained from non-dimension derivation, 25 variable conditions for each particle size and fluid velocity were set. Through separate calculations, the equation for bubble rise and fall was derived. By calculating the ratio of drag and buoyancy for each variable, if the drag force acting on the bubble was greater than buoyancy, the bubble falls, and bubbles are not reduced. If the buoyancy is larger than drag, the bubble rises, and the bubble is reduced. Through the analysis, the rise and fall of the bubble were confirmed, and the results were consistent with the separate numerical calculations.

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참고문헌

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