• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.5
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• pp.14-22
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• 2007

A reversed trapezoidal fin with variable lateral surface slope is optimized using a two-dimensional analytic method. For a fin base boundary condition, convection from the inside fluid to the inside wall and conduction from the inside wall to the fin base are considered. Heat loss from the fin tip surface is not ignored. The maximum heat loss at the practical fin length, the corresponding optimum fin efficiency, fin length and fin base height are presented as a function of the fin inside and outside convection characteristic numbers. One of the results shows that the optimum fin shape becomes 'fatter and shorter' as the ratio of fin tip height to base height increases.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.10 s.253
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• pp.987-995
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• 2006

A reversed trapezoidal fin with the fluid in the inside wall is analyzed and optimized in this study. As a fin base boundary condition, the heat transfer from inside wall fluid to the fin base is considered. The values of fin base temperature with the variations of inside wall fluid convection characteristic number and fin base length are listed. The heat transfer, fin effectiveness, fin length and fin base height are optimized as a function of fin base length, convection characteristic number ratio, fin shape factor and fin volume.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.7
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• pp.455-461
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• 2008

A reversed trapezoidal fin with variable fin base thickness is optimized using a two-dimensional analytical method. For the fin base boundary condition, instead of a constant temperature, heat transfer from the inside fluid to the fin base is considered. Heat loss from the fin tip is not ignored. The maximum heat loss, corresponding optimum fin effectiveness, fin length and base height are presented as a function of the fin base thickness, shape factor and volume.

• New & Renewable Energy
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• v.2 no.1 s.5
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• pp.46-55
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• 2006

The performance enhancement of heat exchanger in the drying system using solar collector with evacuated tubes is analyzed. First, for this analysis, the heat loss from a reversed trapezoidal fin attached at the pipe is calculated as a function of convection characteristic number ratio, fin base length and fin tip length. Also, the optimum heat loss and fin tip length of the fin under certain conditions are presented. The overall surface effectiveness of the cylinder with reversed trapezoidal fins in the heat exchanger are shown as a function of half fin base height, fin lateral slope and fin tip length.