الفهرس 
Direct solar cookersOnly 14 pages are availabe for public view
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Abstract
Two thermal applications are designed, manufactured and studied in this work which are a box type solar cooker with different types of top glass covers and a passive solar fruit drier with a cabinet of multi-interior sizes integrated with a flat plate collector as a heater for the drier. The solar cookers were tested under various conditions using water as a cooking fluid with single glass cover, double glass cover and honeycomb glass cover to minimize the top losses and the solar drier was tested under some parametric and weathering conditions using grapes as a drying product. Temperature measurments at different parts from the cookers were determined through connected thermocouples in cooporated with digital muitimater. Also the convection and radiation heat losses coefficients were calculated and the thermal power losses in each cooker in horizontal and tilted (30•‹) positions. The maximum calculated values of the convective heat losses coefficients, h,, in horizontal position for the single glass cover cooker was 4.2 w/m2.K, while that in the case of double glass cover cooker (SC1) and honeycomb glass cover solar cooker (SC2) were 3.5 WI~~.K3 ,w /m2.~re spectively. Also the maximum caiculated values ofthe radiative heat losses coefficient, h, for single glass cooker was 9.7 w/m2.K, while that for (SC1) and (SC2) were 7.2 IV/rn2.~a nd 7.7 wlrn2.K respectively. The maximum calculated values of the thermal power losses due to convection, &.maa. in the three cookers models (Single glass cover cooker, (SC1) and (SC2)) were 79 W, 36.5 W and 24 W respectively. While the thermal power losses due to radiation (maximum values) reduced from 163 W for single glass model to 71 W and 60.8 W for (SC1) and (SC2). We have found that the variation of the top cover from single glass to double glass to honeycomb cover has been minimized the top radiative and convective heat losses. where double glass cover cooker (SC1) performed 16%.