الفهرس 
introduction
drying analysisOnly 14 pages are availabe for public view
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Abstract
In this study, The Indirect-mode forced convection solar dryer is investigated. The Indirect-mode forced convection solar dryer essentially consists of a solar air heater, drying chamber, and a blower to duct the heated air to the drying chamber. Since, the solar air heater is the most important component of the solar drying system, improvement of the design of the solar air heater would lead to better performance of the drying system. Therefore, three types of double pass solar air heaters with flat (DPFPSAH), v-corrugated (DPVCPSAH) and finned (DPFIPSAH) absorber plates are designed and constructed to compare their thermal performance experimentally. Transient mathematical models for the DPFPSAH, DPVCPSAF and DPFIPSAH operating under forced convection mode are presented. Suitable computer programs are prepared for the solution of the energy balance equations for different elements of the three heaters. To validate the proposed theoretical models, comparisons between experimental and theoretical results are performed. The theoretical predictions indicated that the agreement with the measured performance is fairly good. Comparisons between the measured outlet temperatures of flowing air, output power and overall heat losses of the flat, v-cormgated and finned plate solar air heaters are also presented. Moreover, a theoretical. study is carried out to optimize the thermal efficiency, pressure DROP and themo-hydraulic efficiency of the three types of solar air heaters. The results showed that the outlet temperature of the DPVCPSAH is higher than that of the DPFPSAH and DPFIPSAH by 2.1 -7.6 and 2.1-9.7%, respectively. The thermal efficiency of DPVCPSAH is higher than that of DPFPSAH and DPFIPSAH by 10.5-14.3 and 19.5-21.7%, respectively.