TY - JOUR
TI - Thermal and exergetic investigation of a solar dish collector operating with mono and hybrid nanofluids
AU - Pavlović Saša R
AU - Bellos Evangelos A
AU - Stefanović Velimir P
AU - Djordjević Milan M
AU - Vasiljević Darko M
JN - Thermal Science
PY - 2018
VL - 22
IS - 15
SP - 1383
EP - 1393
PT - Article
AB - The use of solar dish thermal collectors is a promising choice for designing  sustainable energy systems. The use of nanofluids is a new way for enhancing  the thermal performance of solar collectors because of their improved thermal  properties. The objective of this study is to investigate the use of mono and  hybrid nanofluids in a solar dish collector in order to determine which kind  of nanofluids leads to higher performance enhancements. The analysis is  conducted with a developed thermal model in Engineering Equation Solver and  the collector is studied thermally and exergetically. The examined hybrid  nanofluid has as base fluid syltherm 800 with 1% Cu and 1% TiO2. Moreover,  the examined mono nanofluids are the syltherm 800 with 2% Cu and syltherm 800  with 2% TiO2. The investigated solar dish collector has a spiral absorber and  it is examined for inlet temperatures from 25°C up to 300°C with a flow rate  of 200 L/h. According to the final results, the use of hybrid nanofluid leads  to higher thermal efficiency enhancement compared to the mono nanofluids  because of the higher increase in the Nusselt number in the flow. More  specifically, the use of the hybrid nanofluids leads to 0.99% mean thermal  efficiency enhancement compared to the pure oil case, while the use of Oil/Cu  and Oil/TiO2 lead to 0.42% and to 0.56% mean thermal efficiency enhancement,  respectively. Moreover, the exergy efficiency is found enhanced with the use  of all nanofluids. The mean exergy efficiency enhancement is 1.21% with the  hybrid nanofluid, while it is 0.73% with Oil/TiO2 and 0.53% with Oil/Cu.  [Project of the Serbian Ministry of Education, Science and Technological  Development, Grant no. III42006: Research and development of energy and  environmentally highly effective polygeneration systems based on renewable  energy resources]