رحيم مطر كوبانأ.د. رافد معلك حنو ن2024-11-052024-11-052021-02-08https://dspace.utq.edu.iq/handle/123456789/188The solar cooker is one of the best, easiest and cheapest ways to use the solar energy to cook food or boil water for sterilization, heating and other uses is to use a solar cooker. The technical solutions of solar cookers will be of great value to solve the problem of the effect of the use of fossil fuel and its high prices, the increase of desertification and the elimination of environmental and health problems. The present work was done using four parabolic solar concentrators manufactured using a parabolic dish, three of them with diameters (96 cm, 120 cm, and 140 cm) with a reflector made of aluminum foil. The fourth solar concentrator was (96 cm) in diameter with a reflector from pieces of mirrors. Metal tin cans with four volumetric capacities (1 liter, 2 liters, 3 liters, and 4 liters) were used as a thermal receiver coated with black paint were used to increase the absorption of concentrated sunlight falling on the surface of the thermal receiver. Seven experiments were conducted on each thermal receiver, four experiments were conducted using the four concentrators separately, while the remaining three experiments were conducted by collecting the solar concentrator of a diameter of (96 cm) with a reflector of aluminum foil with the rest of the solar concentrators, where the data for each experiment are measured and recorded (the experiment time (t), the beam solar intensity (𝐼𝑏) falling on the concentrator aperture area (𝐴𝑎), the water temperature (𝑇𝑤), the surface temperature of the thermal receiver in the place of the concentrated solar incident on it (𝑇𝑎𝑏𝑠), the ambient air temperature (𝑇𝑎𝑚𝑏) and ambient air velocity (𝑉𝑎𝑖𝑟) for calculating the important parameters of the parabolic solar cooker, which are (the optical efficiency (𝜂𝑜) of the solar concentrator, the amount of heat received by the aperture of the solar concentrator (𝚀𝑠), the heat losses from the receiver by radiation and convection (𝚀𝑙𝑜𝑠𝑠), the amount of useful heat used by the receiver (𝚀𝑢𝑠𝑒𝑓𝑢𝑙), the collector efficiency (𝜂𝑐), overall thermal efficiency (𝜂𝑢) and cooking power (P)). The experiments were conducted from the roof of the house in Nasiriyah city, southern Iraq, from September 2020 until April 2021. The following results were reached : The optical efficiency of the solar cooker depends on the quality of the reflective material used in the concentration dish, the quality of the surface of the receiver, and the quality of its coating, in addition to the area of the receiver shade reflected on the concentration dish. The amount of concentrated heat reflected by the concentration dish affected by the diameter of the dish, its optical efficiency, the quality of the reflector used, and the accuracy of tracking the sun. It was observed that the thermal losses increased with the increase in the focus area on the surface of the receiver, the increase in the velocity of the ambient air, and the increase in the temperature of the receiver surface, meaning that the ambient conditions greatly affect at the increase in thermal losses. As for the amount of useful heat used by the receiver, it increased with an increase in the diameter of the concentration dish, the quality of the reflective material, and the reduction of thermal losses. It was the highest possible when combining two solar concentrators. The collector efficiency or concentration efficiency was high by increasing the diameter of the concentration dish, combining two concentration dishes, increasing the optical efficiency, reducing thermal losses and accurate tracking the sun, and it was highest possible when combining two solar concentrators. The overall thermal efficiency was affected by the cooking period, the mass of water used, the combination of two concentration dishes, the diameter of the concentration dish, the amount of solar radiation captured by the reflector and the accuracy of tracking the sun too, and the overall thermal efficiency was greater when combining two solar concentrators. The cooking power increased by increasing the mass of water or food prepared for cooking and reducing the cooking time. Despite the low overall thermal efficiency and cooking power of the solar cooker, it is recommended for its easy manufacture, low financial costs, and no harm to humans and the surrounding environment.text::thesis::master thesis