Analysis of Solar Radiation and Heat-Efficiency in Semi-Greenhouse Type Solar-Dehumidification Lumber Dryer

반온실형(半溫室型) 제습(除濕).태양열(太陽熱) 목재(木材)드라이어의 일사량(日射量)과 열효율분석(熱效率分析)에 관(關)한 연구(硏究)

Semi-greenhouse type solar-dehumidification drying of oak was carried out to investigate the possibility to dry wood using solar energy in Korea. The energy balance equation was set up, considering all the energy requirements, and the solar radiation was calculated to analyze the efficiencies of solar dryer with and without the dehumidifier. The average temperature inside dryer and collector rose up to $52^{\circ}C$ and $70^{\circ}C$, respectively. The average daily total beam, diffuse, and ground-reflected radiations were 7.27MJ, 8.70MJ, and 0.33MJ on the roof and 2.08MJ, 4.84MJ, and 5.37MJ on the south wall collector, respectively. Heat efficiency of solar dryer was 14.04% with dehumidifier and 13.13% without dehumidifier. The energy required to remove 1g of water from wood was 0.0289MJ/g in solar-dehumidification drying and 0.0310 MJ/g in semi-greenhouse type solar drying.