• 설비공학논문집
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• 제18권1호
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• pp.7-16
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• 2006

Both the computational and experimental analysis have been conducted in this study to develop the high efficiency agriculture products dryer by the uniform thermal flow distribution in the drying room. It has been developed based on the results of the computation and experiment in the conventional dryer to improve the thermal flow distribution in drying room. The developed dryer can be prevented the local concentration of the heated wind and achieved the uniform flow distribution using the installation of vertical branch ducts, ribs, guide vanes and porous plates. As a result, the developed dryer reduced the fuel consumption up to $15\%$ and the electricity consumption up to $31.5\%$ compared with the conventional dryer.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.636-641
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• 2008

Heat pump drying has a great potential for energy saving due to its high energy efficiency in comparison to conventional air drying. The heat pump dryer is usually operated at the temperature less than $50^{\circ}C$ and the drying temperature is limited to the operating temperature of the heat pump system. In order to increase the drying temperature, the special box-type heat pump dryer has been developed. The dryer uses the two-cycle heat pump system which has the two heat pump cycles for high and low temperature heating. The high temperature cycle uses the refrigerant 124 to get the temperature greater than $80^{\circ}C$ and the low temperature cycle uses the refrigerant 134a. The drying experiment has been carried out to figure out the performance of the dryer with the selected drying material.

• Journal of Biosystems Engineering
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• 제8권2호
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• pp.62-68
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• 1983

This study was to examine the drying characteristics of barley and the effect of moisture content of barley on milling performance. A barley variety, Jogang, having 35.0% of initial moisture content was used for this experiment. Thermo-hydrostatic dryer which consists of blower, condensor, heater, humidifier, drying chamber and control box, etc., was used for the drying experiment. The change in the weight of a barley sample was continuously measured by means of the ring type load cell installed inside the drying chamber. Milling test runs the samples having the predetermined moisture content were taken from each drying test run. A laboratory type barley miller was used for the milling test. The results of the study are summarized as follows: 1. The drying constants (k) applied for the thin layer drying model, (M-Me)/(Mo-Me) = $Ae^{-kt}$ were 0.155, 0.259 and 0.548, respectively, at the three levels of drying temperatures, $40^{\circ}C$, $50^{\circ}C$ and $60^{\circ}C$. The drying constants complied with the Arrhenius Equation, K = Ko exp (-C/T), were determined as $Ko=1.901455{\times}10^8$ and C = 6563. 2. The laboratory milling test indicated that the highest milled and head barley recovery was resulted from the sample which was dryed at $40^{\circ}C$. In general, the increase in the drying temperature from $40^{\circ}C$ to $60^{\circ}C$ indicated a negative effect on milling yields. 3. Also, the sample having 15% M.C. presented the highest milled and head barley recovery among the five moisture content levels (12, 15, 18,21 and 24%).