• 산업기술연구
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• 제28권B호
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• pp.3-7
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• 2008

A cylindrical pin fin with variable fin base thickness is optimized based on fixed outer radius by using the one dimensional analytic method. Heat loss from the pin fin with fixed outer radius is presented as a function of the fin length. The ratio of in length for optimum heat loss to that for the maximum heat loss is listed. The maximum heat loss and effectiveness and the fin length for the optimum heat loss are presented as a function of fin base thickness and outer radius. One of the results presents the maximum effectiveness decreases rapidly first and then decreases slowly as the fin outer radius increases.

• 신재생에너지
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• 제5권1호
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• pp.40-46
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• 2009

Optimization of a rectangular profile annular fin with variable pipe inside radius is presented. This optimum procedure is based on fixed fin height and is made by using variables separation method. The optimum heat loss, corresponding optimum fin length and optimum fin efficiency are presented as a function of pipe inside radius, fin half height, inside fluid convection characteristic number and ambient convection characteristic number. One of results shows that the optimum fin length increases linearly with increase of pipe inside radius for fixed fin height and fin base radius.

• 대한기계학회논문집B
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• 제34권3호
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• pp.229-235
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• 2010

원관 내부반경이 변하는 사각형상 환형 훤의 최적 값들이 변수 분리법에 의하여 제시된다. 최적의 열손실이 존재할 수 있는 주위 대류특성계수의 범위가 나열된다. 최적 열손실, 그와 관련된 최적의 훤 유용성, 훤 길이 그리고 훤 높이가 원관 내부반경, 내부유체 대류특성계수, 훤 체적, 그리고 주위 대류특성계수의 함수로 표현된다. 결과 중 하나는 훤 체적과 훤 바닥반경이 고정되었을 때 최적 열손실, 유용성 그리고 훤 길이는 원관 내부반경의 증가에 따라 선형적으로 증가함을 보여준다.

• 대한기계학회논문집B
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• 제32권11호
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• pp.817-823
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• 2008

A pin fin with variable fin base thickness is optimized based on the ratio of heat loss to the maximum heat loss using a two-dimensional analytic method. The temperature profile along the normalized radius position in the fin is presented. For fixed fin outer radius, the optimum heat loss, fin length and efficiency as a function of fin base thickness, outer radius, convection characteristic numbers ratio and ambient convection characteristic number are presented. One of the results shows that the effect of fin outer radius and ambient convection characteristic number on the optimum fin length is remarkable.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.642-645
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• 2008

A pin fin with variable fin base thickness is analysed by using the one dimensional analytic method. Heat loss and fin thermal resistance are presented as a function of the fin base thickness, pin fin outer radius and convection characteristic numbers ratio. The relationship between the fin outer radius and fin base thickness for the same amount of heat loss is shown. One of the results indicates the fin thermal resistance decreases as the fin outer radius and/or convection characteristic numbers ratio increase whereas the fin thermal resistance is independent on the variation of fin base thickness.

• 산업기술연구
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• 제29권B호
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• pp.3-7
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• 2009

A cylindrical pin fin with inside fluid is optimized based on fixed fin volume by using the one dimensional analytic method. Heat loss from the fin and the pin fin radius for fixed fin volume is presented as a function of the fin length. Temperature variation of the fin with the variation of ambient and inside fluid convection characteristic numbers and fin base thickness is listed. The maximum heat loss at the practical fin length and corresponding optimum fin length and radius are presented as a function of fin base thickness, inside convection characteristic number, fin volume and ambient convection characteristic number. One of the results shows that the optimum pin fin shape becomes relatively fatter as the fin volume increases.

• 산업기술연구
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• 제36권
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• pp.17-22
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• 2016

A circular pin fin (CPF) and a half circular pin fin (HCPF) are by using the one-dimensional analytic method. For these two fins, 90% of the maximum heat loss, Corresponding fin length for 90% of the maximum heat loss, fin effectiveness and fin efficiency are compared as functions of convection characteristic number and fin radius. Also, the ratio of heat loss from the HCPF to that from CPF listed with variation of fin length when the fin volumes are the same. One of the results shows that the efficiency of a CPF is larger than that of a HCPF while the effectiveness of a CPF is smaller than that of a HCPF when convection characteristic number, fin length and fin radius are the same.

• 한국추진공학회지
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• 제7권1호
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• pp.1-9
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• 2003

체적이 일정할 때 복사열을 고려하지 않은 직각 형상 환형 휜을 2차원 해석적 방법을 사용하여 최적화한다. 휜 바닥 경계 조건을 위하여 파이프 내의 유체로부터 파이프 내벽까지의 대류와 파이프 내벽으로부터 휜 바닥까지의 전도를 고려한다. 휜 끝 반경을 통한 열손실은 무시되지 않는다. 최대 열손실, 최대 열손실이 일어날 때의 최적의 휜 끝 반경 그리고 최적의 휜 두께의 반이 휜 바닥 반경, 휜 표면 주위의 Biot 수 그리고 파이프 내의 Biot 수의 함수로 나타내어진다. 결과들은 1) 파이프 내의 Biot 수와 휜 주위의 Biot 수가 증가함에 따라, 휜 바닥 반경이 감소함에 따라 최대 열손실은 증가하며 2) 파이프 내의 Biot 수가 감소하거나 휜 바닥 반경과 횐 주위의 Biot 수가 증가함에 따라 최적의 휜 두께는 증가한다.

• 산업기술연구
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• 제31권A호
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• pp.21-25
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• 2011

A comparison of temperature distributions along the fin length coordinate between two different fin tip boundary conditions for a circular pin fin is made by using the one-dimensional analytic method. One tip boundary condition is the actual fin tip boundary condition and fin tip temperature is arbitrarily given for another fin tip boundary condition. The value of the fin base temperature is depend on the fin base thickness and fin radius. One of the results shows that the temperature distribution along the fin length coordinate for the actual fin tip boundary condition and that for the arbitrarily given fin tip temperature are the same if the arbitrarily given fin tip temperature and the fin tip temperature for the actual fin tip boundary condition are the same.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제12권1호
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• pp.25-32
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• 2008

A pin fin is optimized based on the increasing rate of heat loss by using a two-dimensional analytic method. The optimum heat loss, corresponding optimum thermal resistance and fin length are presented as a function of the fin base thickness, convection characteristic numbers ratio, fin outer radius and ambient convection characteristic number. One of the results shows that both the optimum heat loss and fin length decrease linearly whereas the optimum thermal resistance increases very slightly with increase of the fin base thickness.