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급기 예열 열교환기에서 에칭 표면 특성이 응축 열전달에 미치는 영향에 관한 연구

A Study on the Effects of Etching Surface Characteristics on Condensation Heat Transfer in Pre-heating Exchanger

  • 석성철 (국민대학교 대학원 기계공학과) ;
  • 황승식 (국민대학교 대학원 기계공학과) ;
  • 최규홍 (국민대학교 대학원 기계공학과) ;
  • 신동훈 (국민대학교 대학원 기계공학과) ;
  • 정태용 (국민대학교 기계공학과)
  • Seok, Sungchul (Dept. of Mechanical Engineering, Graduate School of Kookmin University) ;
  • Hwang, Seung Sik (Dept. of Mechanical Engineering, Graduate School of Kookmin University) ;
  • Choi, Gyu Hong (Dept. of Mechanical Engineering, Graduate School of Kookmin University) ;
  • Shin, Donghoon (Dept. of Mechanical Engineering, Graduate School of Kookmin University) ;
  • Chung, Tae Yong (Dept. of Mechanical Engineering, Kookmin University)
  • 투고 : 2014.01.06
  • 심사 : 2014.05.28
  • 발행 : 2014.06.30

초록

일반 가정용 보일러의 열효율을 증진시키기 위해서 콘덴싱 보일러에 부착되는 급기 예열 열교환기의 응축 열전달에 대한 실험을 수행하였다. 본 연구에서는 스테인리스의 표면에 대하여 에칭을 이용하여 표면 거칠기를 부과하였다. 그리고 열전달 성능 평가를 위해 대향유동 열교환기를 폴리카보네이트로 제작하였고 원판과 비교 실험을 수행하였다. 그 결과 에칭 처리한 모든 시편의 총괄열전달계수는 원판에 비해 증가하는 것을 확인할 수 있었고, 에칭 시간이 60초인 시편에서 평균 15%까지 증가하였다. 그리고 AFM 장비를 이용하여 표면 특성에 대한 분석을 통하여 열전달 증진 요인에 대해 연구하였다.

In order to improve the heat efficiency of the general residential boiler, we performed an experiment of condensation heat transfer to air pre-heating exchanger adhered to the condensing boiler. In this study, surface roughness was imposed on the surface of stainless steel by etching. And in order to evaluate the heat transfer performance on each plate, the counter flow heat exchanger fabricated with polycarbonate in used. As a result, on etching treated plate's overall heat transfer coefficient is higher than the original plate. And etching treated plate during 60 seconds with etchant is the to average 15% compared to bare stainless steel. And we studied the heat transfer enhancement factor through the analysis of surface characteristics using AFM.

키워드

참고문헌

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