• 한국산학기술학회논문지
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• 제22권3호
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• pp.30-35
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• 2021

본 연구는 다양한 가이드 핀 구조와 경계 파라미터가 폐열 회수 열전발전용 열교환기의 열적 성능에 미치는 영향에 대하여 다룬다. 가이드 핀 구조의 영향을 확인하기 위하여 ANSYS 19.1 소프트웨어를 사용하여 핀이 없는 유형, 삼각형 핀, 원형 핀, 원형 핀과 삼각 핀 조합 열교환기의 열전달율 및 압력 강하 특성을 수치해석 하였다. 원형 핀과 삼각 핀 조합 열교환기는 핀이 없는 열교환기, 원형 핀 또는 삼각 핀이 있는 원형 핀 또는 삼각 핀 열교환기와 비교하여 각각 27.0%, 5.2% 및 1.5% 높은 열전달율을 나타내었다. 그리고 복합 핀 열교환기의 압력강하는 핀이 없는 열교환기와 비교하여 28.3% 높았지만, 복합 핀 열교환기와 비교하여 9.2% 및 10.5% 낮은 압력강하 특성을 나타내었다. 최적모델로서 복합 핀 열교환기는 최대 고온 가스 및 냉각수 질량 유량, 최고 고온 가스 온도 그리고 최저 냉각수 온도 조건에서 최대 열전달율 5664.9 W 및 최대 압력강하 1454.02 Pa을 나타내었다.

• 설비공학논문집
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• 제19권12호
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• pp.874-882
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• 2007

The effects of a guide fin blade on the flow characteristics in a ventilating axial fan were investigated experimentally. The guide fins were setup onto the pressure surface of the blade, and their effects on the flowrate were evaluated. Two types of the guide fin blade were designed. One is the stem fin blade, and the other is the radial fin blade. The stem fin is designed normal to the circumference of a circle, and the radial fin is designed along the circumference of a circle. The results from the guide fin blade fans are compared with that of the blade without guide fins. The position and the geometry of the radial fin setting up on the blade have an effect on the increase of flowrate with the minor sacrifice of rotational speed of the blades. The radial fin positioning at 0.84 times blade diameter shows highest performance in the flowrate. The increase of the blade weight resulting from applying the guide fins shows minor effect on the variation of rotational speed of the blades.

• 대한기계학회논문집B
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• 제22권6호
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• pp.849-859
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• 1998

The heat generated in an induction motor is mostly dissipated through the frame. The study on the heat transfer characteristics of a newly manufactured finless TEFC(Totally Enclosed Fan Cooled) induction motor showed/that it had an unsuitable structure in view of the heat transfer. The angle of the cooling air flow was very large and the ribs disturbed the air flow and partially generated the wake region on the frame. In the wake region the temperature was very high. Thus the heat transfer coefficients were lower than those of the frame with fins. Also was investigated the heat transfer characteristics of the motor frame by installing various guide vanes in the fan-side end cap. An optimum heat transfer case was found and the average heat transfer coefficient of the frame was 70% higher and the average coil temperature measured by the resistance method was 9 deg. C lower than that of the frame which had no guide vanes.