Browsing by Author "Kamil, Nuredin"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Computational and Experimental Analysis of Ice Thermal Storage with Solar Refrigerator
    (Addis Ababa University, 2020-06) Kamil, Nuredin; Yilma, Tadesse (PhD)
    In rural areas of Ethiopia the grid electricity supply coverage is very low, which is about 2%. As result of this dairy product preservation before supply to local market is difficult especially for night time collected milk. However, utilization of direct coupled PV powered solar refrigerator incorporated with Ice thermal storage able to preserve the products until market. The use of Ice thermal storage can avoid the use of solar batteries. The study includes the design, manufacture the prototype and experimental testing and computational modeling of PV powered solar refrigerator. As a case study Adama city Ethiopia is selected for the experimental test, the solar radiation of the site is analyzed. The minimum daily average solar radiation is determined at a month of August which is . To preserve 5L milk, MT3.5DC compressor and 140W PV panel are selected. The operating point of compressor is obtained and the minimum solar radiation required for the solar refrigerator is Computational simulations using ANSYS-Fluent is conducted to determine the amount of ice produced as a thermal storage for night time preservation and the average temperature of waterice during solidification process. The system produced nearly 1kg solid ice with a mean temperature of . During night time which is the discharging process of the ice the milk got chilled from and maintained this temperature for more than 12hours. Then, the model is manufactured and tested for its performance. During the experimental test solar radiation was simulated virtually with DC power supply due to frequent intermittent nature of the radiation. From the experiment, it was observed that the average water-ice temperature was -12.5 o C. In the discharging process the milk temperature was reduced from 310K to 274K within 12 hours. Also, the milk temperature is reached to a range of to with in 4hours duration and satisfies the FAO standard. CFD simulation was validated by experimental test, with 6% maximum deviation.