Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Preventing Freezing of Condensate inside Tubes of Air-Cooled Condenser

공랭식 응축기 관내 응축수 동결 방지에 관한 연구

  • Joo, Jeong-A (Dept. of Mechanical Design Engineering, Chonbuk Nat'l Univ.) ;
  • Hwang, In-Hwan (Dept. of Mechanical Design Engineering, Chonbuk Nat'l Univ.) ;
  • Cho, Young-Il (Mechanical Engineering and Mechanics, Drexel Univ.) ;
  • Lee, Dong-Hwan (Dept. of Mechanical Design Engineering, Chonbuk Nat'l Univ.)
  • 주정아 (전북대학교 기계설계학과) ;
  • 황인환 (전북대학교 기계설계학과) ;
  • 조영일 (미국 드렉셀대학교 기계공학과) ;
  • 이동환 (전북대학교 기계설계학과)
  • Received : 2012.01.30
  • Accepted : 2012.05.22
  • Published : 2012.08.01
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Abstract

An air-cooled condenser is a device that is used for converting steam into condensate by using ambient air. The air-cooled condenser is prone to suffer from a serious explosion when the condensate inside the tubes of a heat exchanger is frozen; in particular, tubes can break during winter. This is primarily due to the structural problem of the tube outlet of an existing conventional air-cooled condenser system, which causes the backflow of residual steam and noncondensable gases. To solve the backflow problem in such condensers, such a system was simulated and a new system was designed and evaluated in this study. The experimental results using the simulated condenser showed the occurrence of freezing because of the backflow inside the tube. On the other hand, no backflow and freezing occurred in the advanced new condenser, and efficient heat exchange occurred.

공랭식 응축기는 대기중의 공기를 이용해 스팀을 응축수로 전환시키는 발전용 냉각설비이다. 추운 겨울철, 공랭식 응축기는 열교환부 관내의 응축수가 동결되어 튜브 자체가 터지는 심각한 동파 문제를 수반한다. 이는 기존 공랭식 응축기 시스템이 가지는 튜브 출구의 구조적 문제로 인한 응축되지 않은 스팀 및 비응축성 기체의 역류가 주요 원인이 된다. 따라서 본 연구에서는 유사 모의 공랭식 응축기 시스템을 설계 및 제작하여 기존의 공랭식 응축기 시스템이 가지고 있는 문제점을 구현하고, 이를 해결하기 위한 설계가 가능함을 실험적으로 증명하였다. 기존 공랭식 응축기 시스템의 작동 원리와 유사한 조건에서 실시한 실험에서 역류에 의한 튜브 동결을 관찰할 수 있었다. 반면 신개념 공랭식 응축기 시스템을 적용한 실험에서는 역류 및 동결 발생없이 열교환이 잘 이루어짐을 확인할 수 있었다.

Keywords

References

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