Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi

Yazarlar: Selahattin ÇELİK, Mahmut ALKAN

Konular:Mühendislik, Makine

DOI:10.28948/ngumuh.445434

Anahtar Kelimeler:Solid oxide fuel cells,Fuel utilization efficiency,Performance

Özet: Solid oxide fuel cells (SOFCs) are energy generators with high energy conversion efficiencies.  Increasing the amount of hydrogen and air sent to the fuel cells improves performance. However, since the amount of unused fuel increases as a result of the increase in the hydrogen supply, the fuel utilization efficiency decreases. In this study, the fuel utilization efficiency of a solid oxide fuel cell at different flow rates is investigated. It is found that the change in flow rate has a significant effect on the fuel utilization efficiency and the fuel utilization is also affected by operating voltage at constant flowrates. The literature on SOFCs do not generally describe the voltage and flowrate values where the resultant fuel utilization is obtained. This situation is based on the power but it can cause the results to be misleading. In this study, the power based fuel cell efficiencies are compared. It is observed that up to 85% of the fuel utilization efficiency can be achieved in the high operating voltage range and 90 mW.cm-2 peak power density is obtained at this efficiency. At high operating power densities (225  mW.cm-2), on the other hand, the fuel utilization efficiency was found to be very low (30%).

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