Study and Feasibility of a Flat Collector Cooker using Vegetal Heat Transfer Fluid

Solar cookers currently produced are solar systems that use parabolic heat transfer to concentrate sun rays on a cooker. The new trend is focus on the cooker that uses a flat collector operating as a thermosiphon where the heat transfer fluid (oil) flows by natural convection. They are developed to address household needs at a lower cost, making them popular both in terms of research and use. Some of vegetable oils were previously investigated and which could be used as heat transfer fluids in such systems. A digital study using vegetable oil called "Kibi oil", an artisanal oil produced in Côte d’Ivoire, as a coolant, was conducted under poor weather conditions to calculate temperatures that could be reached in these cases. In the Sahelian zone, conditions are much better than these, and we can expect fairly excellent results.

This study focused on temperature variation at different areas (1, 2, 3 and 4 specified in the diagram) of the cooker, on the mass flow of the fluid throughout the study day and to some quantities which enable to follow the performance of the solar collector of the stove. Sunlight measurements used are those of the city of Abidjan made in September, a very cloudy day with poor weather conditions. Temperature T3, very close to that of the hot plate, was around 110 °C between 10:30 am and 12:30 pm, which enables to cook certain dishes during this period. It should be noticed that at the exit of the flat panel collector, over the same period, the temperature is around 120 ° C. At that same time, the collector efficiency varies around 30%.