INVESTIGATION OF THE EFFECT OF OPERATING PARAMETERS ON NERNST VOLTAGE IN HYDROGEN-OXYGEN FUEL CELLS

Authors : Muhittin Bilgili, Yunus Emre Gönülaçar

Pages : 59-69

Doi:10.47480/isibted.1494033

View : 61 | Download : 94

Publication Date : 2024-06-03

Article Type : Research Paper

Abstract :In hydrogen-oxygen fuel cells, operating parameters have an influence on the maximum expected open circuit (Nernst) voltage. Even though fuel cells have been the subject of many research, none of them have theoretically investigated the impact of various operating parameters, particularly concerning Nernst voltage and maximum thermodynamic efficiency. In this study, a computer program was developed to theoretically determine the effect of various operating parameters on the Nernst voltage in hydrogen-oxygen fuel cells. This computer program was developed in MATLAB to mathematically examine the effects of hydrogen and oxygen mole ratios, anode and cathode pressures, and operating temperatures on the maximum expected open circuit voltage. When calculating Nernst voltages and maximum thermodynamic efficiency for fuel cell reactions containing water as a by-product, the effects of higher heating value (HHV) and lower heating value (LHV) are also considered in the solutions. As a result, it was also concluded that temperature increase reduces the fuel cell Nernst voltage and maximum thermodynamic efficiency. Therefore, it was observed from the figures that the best conditions for the Nernst voltage occur when HHV is assumed, the temperature is 353 K, the mole ratios of hydrogen and oxygen are 1.0, the anode and cathode pressures are 5 atm and 6 atm, respectively. In terms of thermodynamic efficiency, it was determined that there was a maximum increase of 92.2% in the LHV assumption compared to the HHV assumption at the temperature of 1000 K, provided that other operating parameters were kept constant.
Keywords : Nernst voltajı, Yakıt hücresi, Termodinamik verim, Hidrojen oksijen