• 대한기계학회논문집B
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• 제26권1호
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• pp.66-73
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• 2002

Fin effectiveness and efficiency of a thermally asymmetric triangular fin are represented as a function of the ratio of fin lower surface Biot number to upper surface Biot number and the non-dimensional fin length. For this analysis, two dimensional separation of variables method is used. When fin effectiveness is 2 and efficiency is 90%, the relationship between the non-dimensional fin length and the ratio of fin lower stir(ace Biot number to upper surface Biot number is shown. The relationship between the non-dimensional fin length and the upper surface Biot number for the same condition is also presented.

• 한국물환경학회지
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• 제22권4호
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• pp.614-618
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• 2006

The purpose of this paper, was to compare its result with both the settler of inclination plate and the settler of stick fin through the pilot test to know optimized interval of fin. According to intervals of fin, We get most optimized interval of fin in laboratory is inclination plate with $60^{\circ}$ and wide of fin with 50 mm, interval of fin with 150 mm. The result of laboratory showed 67.6~70.6%, 70.4~74.2% for the settler of inclination plate, the settler of inclination plate stick fin. The sedimentation efficiency of the settler of inclination plate stick fin showed 2.8% higher than the sedimentation efficiency of the settler of inclination plate. From now on, Inclination plate settler stick fin requirement in study.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 학술대회
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• pp.137-142
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• 2008

The purpose of the present study is to investigate the convective heat transfer characteristics and the validity of fin efficiency of the circular finned-tube heat exchanger by using commercial CFD code. The heat transfer coefficient obtained by using the laminar model was 22% overestimated to the experimental data. The fin surface temperature compared with the experimental data measured by the liquid crystal method. The fin efficiency by the present numerical experiment, defined as normalized and averaged fin surface temperature, was greater than the theoretical fin efficiency and the difference is increased at high value of the factor m.

• 한국전산유체공학회지
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• 제14권4호
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• pp.7-12
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• 2009

The purpose of the present study is to investigate the convective heat transfer characteristics and the validity of fin efficiency of the circular finned-tube heat exchanger by using commercial CFD code. The heat transfer coefficient obtained by using the laminar model was 22% overestimated to the experimental data. The fin surface temperature compared with the experimental data measured by the liquid crystal method. The fin efficiency by the present numerical experiment, defined as normalized and averaged fin surface temperature, was greater than the theoretical fin efficiency and the difference is increased at high value of the factor $mr{\phi}$.

• 상하수도학회지
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• 제12권4호
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• pp.106-111
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• 1998

In this paper,to know sedimentation efficiency compared with sedimentation efficiency's experiment result by general and inclination plate settler, its and fin stick of inclination plate. Experiment result is inclination plate settler increase sedimentation efficiency's 6.96% than general settler, When fin stick of inclination plate is the optimum condition of one side, inclination plate's angle $60^{\circ}$, fin's width 67mm, fin's interval 200mm, sedimentation efficiency of many experimental condition increase 6.63% than inclination plate settler. A studdy on the site plottage through the result, Water inclination plate settler of the present's application reduce 30% of its than general settler. According to the above statements, fin stick of inclination plate's sedimentation efficiency is 0.95 times of inclination plate settler's. Concluding remarks, Fin stick of inclination plate reduce 28.5% of its than inclination plate settler.

• 한국자동차공학회논문집
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• 제19권4호
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• pp.24-31
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• 2011

Performance of the asymmetric trapezoidal fin with various upper lateral surface slopes is investigated by using the two-dimensional analytic method. For a fin base boundary condition, convection from the inner fluid to the inner wall, conduction from the inner wall to the fin base and conduction through the fin base are considered. Heat loss and fin efficiency are represented as a function of the fin base thickness, base height, inner fluid convection characteristic number, fin tip length and fin shape factor. One of the results shows that heat loss increases while fin efficiency decreases as the fin shape factor increases.

• 대한기계학회논문집B
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• 제27권5호
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• pp.579-588
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• 2003

Optimum fin effectiveness of geometrically and thermally asymmetric trapezoidal fins is represented as a function of the ratio of the fin bottom to top Biot numbers, the ratio of the fin tip to top Biot numbers and fin shape factor. Optimum fin effectiveness is taken as 98% of the maximum fin effectiveness by comparing the increasing rate of fin effectiveness with that of dimensionless fin length. For this analysis, two dimensional separation of variables method is used. Also, the value of the slope of upper surface of the fin and fin efficiency corresponding to optimum effectiveness are presented.

• 한국자동차공학회논문집
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• 제16권6호
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• pp.81-87
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• 2008

A geometrically asymmetric trapezoidal fin with variable fin base thickness and height is optimized based on the fixed fin base height using a one-dimensional analytic method. The temperature profile along the normalized X position in the fin is presented. For the fixed fin base height, the optimum heat loss, fin length and efficiency as a function of inside fluid convection characteristic number, fin base thickness and height, fin shape factor, convection characteristic numbers ratio and ambient convection characteristic number are represented. One of the results shows that the effect of fin base height and ambient convection characteristic number on the optimum values is remarkable.

• 산업기술연구
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• 제20권B호
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• pp.21-26
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• 2000

Heat loss, fin effectiveness and efficiency of a plate fin are investigated as a function of non-dimensional fin length and Biot number using a two-dimensional separation of variables method. The value of temperature of the left side is set to be different from that of the right side for this plate fin to satisfy the real physical condition. Also temperature distribution within this plate fin is listed. One of the results shows that the fin can be considered to be useful in view of fin effectiveness on the given range of Biot number when non-dimensional fin length is larger than 3.

• 설비공학논문집
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• 제6권2호
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• pp.140-154
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• 1994

Experimental studies were performed to determine the characteristics of flow structure and pressure drop in 15 : 1 scale models of multi-louvered fin heat exchanger in a wide range of variables($L_P/F_P=0.5{\sim}1.23$, ${\theta}=27^{\circ}{\sim}37^{\circ}$, $Re_{LP}=50{\sim}2000$). Flow structure inside the louvered fin was analyzed by smoketube method and new correlations on flow efficiency and drag coefficient were suggested. The new definition for flow efficiency, which modifies the existing flow efficiency, can predict the flow efficiency in the range above mentioned and is represented as a function of Reynolds number, louver pitch to fin pitch ratio, louver angle at low Reynolds number. Drag coefficient which is defined here is a function of Reynolds number, louver pitch to fin pitch ratio, louver angle below critical Reynolds number, and can be represented by a function of louver pitch to fin pitch ratio only above the critical Reynolds number.