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Öğe The efficiency of Al2O3 water nanofluid on a flat plate solar collector(SETCOR publications, 2015) Budak Ziyadanoğulları, Neşe; Yıldız, Cengiz; Argunhan, Zeki; Tekalp, Selen; Yücel, Halit LutfiSolar collectors are particular kind of heat exchangers that transform solar radiation energy into internal energy of the transport medium. One of the most effective methods is replacing the working fluid (water, ethylene glycol, engine oil…) by developing a new class of fluids with a higher thermal conductivity for thermal systems. In the present work the effect of Al2O3-water, as working fluid, on the efficiency of a flat plate solar collector is investigated experimentally. The mass flow rate of nanofluid is 150 Lit/h. The volume fraction of the nanoparticles is 0.2 %, 0.4 % and 0.8 % respectively. The results reveal the impact and importance of each of these parameters. Experimental results reveal that utilizing the nanofluid increases the collector efficiency in comparison to water as an absorbing mediumÖğe Experimental investigation of solar stills integrated with solar water heating collectors(Türk Isı Bilimi ve Tekniği Derneği, 2017-10-31) Argunhan, Zeki; El, Emin; Yıldız, Cengiz; Çakmak, GülşahSolar still is a more practical way of obtaining clean water. In this study, we aimed to improve the efficiency of solar still systems and obtain distilled water at the same time. For this purpose, 5 different solar still systems were designed. Type 1; conventional solar still, Type 2; conventional solar still integrated with solar water heating collector and run via natural convection, Type 3; conventional solar still integrated with solar water heating collector and tubular heat exchanger and run via natural convection, Type 4; conventional solar still placed with plate heat exchanger and integrated with solar water heating collector and run via natural convection, Type 5; conventional solar still placed with plate heat exchanger and integrated with solar water heating collector and run via forced convection. In this study, the experiments were carried out on the parameters influencing the performance, the amount of distilled water obtained, and the efficiency of experiment settings designed in different types; and finally the results were presented. The amount of distilled water and efficiency of conventional solar still were 2389 ml and 51.47%, respectively. Maximum total amount of water and efficiency from natural convection systems were obtained from Type 4, and the values calculated were found as to be 5788 ml and 55.91%. Maximum amount of distilled water and the efficiency were obtained by utilizing forced convection system were found as to be 6068 ml and 58.99%, respectively.Öğe The experimental study of nanofluids on a flat-plate solar collector(Fırat Üniversitesi, 2017) Budak Ziyadanoğulları, Neşe; Yücel, Halit Lutfi; Yıldız, Cengiz; Işık, Mehmet KemalSolar collectors are particular kind of heat exchangers that transform solar radiation energy into internal energy of the transport medium. One of the most effective methods is replacing the working fluid (water, ethylene glycol, engine oil…) by developing a new class of fluids with a higher thermal conductivity for thermal systems. In the present work the effect of Al2O3 -water, as working fluid, on the efficiency of a flat plate solar collector is investigated experimentally. The mass flow rate of nanofluid is 250 l/h. The volume fraction of the nanoparticles is 0.2 %, 0.4 % and 0.8 % respectively. The results reveal the impact and importance of each of these parameters. Experimental results reveal that utilizing the nanofluid increases the collector efficiency in comparison to water as an absorbing medium.Öğe Thermal performance enhancement of flat-plate solar collectors by means of three different nanofluids(Elsevier, 2018-12) Budak Ziyadanoğulları, Neşe; Yıldız, Cengiz; Yücel, Halit LutfiSolar energy, which comes first among renewable energy sources, enables efficient use of energy with many applications due to its low operating cost and environmental friendliness. In this study, we experimentally investigated the effects on thermal efficiency of nanofluid and water as working fluids in flat-plate solar collector hot water solar energy systems. Nanofluids were prepared by adding Al2O3, CuO, and TiO2 nanoparticles at 0.2, 0.4, and 0.8 vol% into distilled water, and then the thermophysical properties (thermal conductivity, viscosity) of the prepared nanofluids were determined. Flow rate was adjusted to 250 l/h at given concentrations for each nanofluid in the experimental setups and data such as collector inlet and outlet temperatures, ambient and tap water temperatures; radiation, humidity, and wind speed were measured and recorded. The obtained data were used to calculate efficiencies according to ASHRAE 93-2003 standards. When compared with water, the results indicated that the use of nanofluid increased collector efficiency.