The Effect of Different Absorber Configurations On The Exergy and The Energy of Parabolic Solar Dish


Abstract: The solar energy is the most important type of energy. The parabolic dish solar collector (PDSC) is the best type among other solar collectors because it is always tracking the sun movement. The exergy and the energy performances of a PDS were analyzed experimentally and numerically. The effect of different coil geometries and different mass flow rates of heat transfer fluid (HTF) were investigated. The PDS has parabolic dish and receiver with diameter (1.5) m and (0.2) m respectively. Concentration ratio is 56.25. The parabolic polar dish was supported by a tracking system with two axes. The types of the copper absorber were used which are: (spiral –helical) coil (SHC) and spiral-conical coil (SCC). The results showed that the useful energy and thermal efficiency are varying with solar radiation variation. The useful energy varying between (480-765) W for (SHC), the thermal efficiency varying between (35.2-39.8) % for (SHC). Exergy efficiency varying between (6.9 –8.6) %. It was shown that the higher values of useful energy for (spiral – helical) absorber was 0.1L/min flow rate.