Usability of parabolic trough type solar energy systems for obtaining hot water

In this study, a new parabolic trough solar collector is designed and its performance in obtaining hot water. Aluminium reflector with 1 m2 aperture area having high reflection property is used. As focus pipe, two different types of receiver pipe made of aluminium and copper are used. Each focus pipe material is tested for five different mass flow rates being 0.0017, 0.0033, 0.0050, 0.0067 and 0.0083 kg/s. In both two test setups, the highest efficiency is seen in 0.0083 kg/s and the highest temperature is obtained in 0.0017 kg/s mass flow rate with copper focus pipe. The highest temperature difference between input and output temperature values is measured to be 73.1 °C. The highest efficiency value for copper focus pipe is found as 74.5%, and for aluminium focus pipe, this value is seen to be 72.7%. Exergy efficiencies of the system are calculated. The highest energy efficiency for 0.0017 kg/s mass flow rate is found as 14.7% for aluminium focus pipe and 15.6% for copper focus pipe. System was modeled with CFD module of ANSYS program, output temperatures of water in the system, fluid velocities, heat distributions, pressure distributions and temperature distributions are modeled. In the simulation made using the program, it was determined that the water outlet temperatures were 5.4% different for the copper tube set and 6% for the aluminium tube set from the experimental results.