Design and Development of a Mixed-Mode Domestic Solar Dryer

Abstract

This work focuses on the design and development of a mixed-mode domestic solar dryer in which the slices of pepper, okra and yam were dried simultaneously by both direct radiation through the transparent glass roof of the drying chamber and by the heated air from the solar collector. The dryer was made up of the solar collector, the desiccant chamber and the drying chamber which contains a rack of three trays. The air comes in through the air inlet and heated up within the solar collector and then channeled through the drying chamber by natural convection where it is utilized for drying purposes. The development was done using locally sourced and readily available materials such as wood, transparent glass sheet, mild steel metal sheet, mosquito galvanized wire mesh and chicken galvanized wire mesh. The maximum temperature attained by the solar collector, drying chamber during test were 69 o C and 55 o C respectively, with a corresponding ambient temperature of 39 o C. The mass of water removal of 43g, 136g and 255g from pepper, okra and yam slices respectively was achieved making use of the passive solar food dryer as against the water removal of 39g, 126g and 218g from pepper, okra and yam slices respectively achieved using the sun drying method which indicates a difference of 4g, 10g and 37g for pepper, okra and yam slices respectively. The rapid rate of drying achieved with the use of this dryer shows that it has the ability to dry food items rapidly to an acceptable moisture content level.

Design and optimization of a domestic solar dryer: an analytical approach

“…, 2023b; Saleh and Badran, 2009; Singh et al. , 2006; Ugwuoke et al. , 2019) but none of them got the acceptance among household users.…”

“…The household sector is responsible for about 61% of global food loss and wastage followed by service and retail sectors (UNEP, 2021). In the past few years, several developments have been made in the field of solar drying (Dubey et al, 2022;Eltawil et al, 2012;Eustache, 2017;Ezekoye and Enebe, 2006;Haque et al, 2018;Kaur et al, 2023;Kumar et al, 2023b;Saleh and Badran, 2009;Singh et al, 2006;Ugwuoke et al, 2019) but none of them got the acceptance among household users. The lower thermal performance, higher heat losses, larger drying time and the obvious intermittent operating behavior are some of the limitations of the solar dryers developed for domestic and small-scale applications (Manchanda et al, 2019;Shimpy et al, 2019).…”

Experimental and simulation studies on the no‐load performance assessment of a domestic solar dryer

“…It was also reported that the higher values of drying temperature and time would result in lower quality product. Ugwuoke et al 19 developed and tested a mixed mode domestic solar dryer for the drying of pepper, okra and yam slices. The maximum dryer temperature was reported to be 55°C, 56°C, and 47°C for the drying of pepper (80 g), okra (190 g), and yam slices (310 g), respectively.…”

Performance assessment of solar dryer integrated with heat energy storage system for food preservation

“…The inclination angle of solar collector (β) from the horizontal surface was found by using the following formula as calculated by Ugwuoke et al (2019).…”