Design and Thermodynamic Analysis of an SOFC System for Naval Surface Ship Application

WOS: 000326097500006Diesel-fueled fuel cell systems can be more clean and efficient energy solutions than internal combustion engines for electric power generation on-board naval surface ships. NATO Navy steam and gas turbine and diesel ships are powered by a naval distillate fuel (NATO symbol F-76). In this study, a 120 kW F-76 diesel-fueled solid oxide fuel cell system (SOFC) as an auxiliary engine on-board a naval surface ship was designed and thermodynamically analyzed. A diesel-fueled SOFC system was compared to diesel-electric generator set in a case naval surface ship

Sustainability and performance analysis of a solar and wind energy assisted hybrid dryer

In this study, energy, exergy and sustainability analysis of the solar and wind energy assisted hybrid drying system were discussed. The drying process was carried out by solar dryer. Wind energy was used to provide the electrical energy required for the operation of the fan in the drying unit. So, no external energy source was required for the drying process. The main purpose of the study was to contribute to the development of an economical and environmentally friendly drying system that was operated using only two different renewable energy sources. The drying characteristics of banana slices were determined in the experiments. It was found that the exergy efficiency of the dryer was in the range of 68.04-83.89%, as a result of the experiments. The system was also examined in terms of waste exergy rate, improvement potential and environmental sustainability. The evaluations showed that the hybrid dryer had 57.7% and 21.52% higher exergy efficiency compared to other conventional solar dryers and solar assisted-hybrid dryers, respectively. Moreover, the energy payback period was determined as 1.36 years. This result clearly indicated that the system can recover the energy it consumed in approximately 38.18% shorter time compared to other solar dryers.(c) 2022 Elsevier Ltd. All rights reserved.This study was promoted by Scientific Research and Projects Unit of Yozgat Bozok University, Turkey with the project number of 6602b-MUEH/20-362.Scientific Research and Projects Unit of Yozgat Bozok University, Turkey [6602b-MUEH/20-362

Numerical investigation of inward solidification inside spherical capsule by using temperature transforming method

In this study, a numerical analysis of the inward solidification of phase change material inside spherical capsule is carried out. The spherical capsule that is subjected to convection from the outside surface initially is not at its melting temperature. The control volume approach and temperature transforming method are applied to solve the dimensionless energy equation. The model solution results are validated through a comparison with published experimental data for similar case and it shows a considerably good agreement. The analysis results show that the larger diameter spherical capsules have significantly greater solidification time compared to those with smaller diameters of spherical capsules. In addition, the entropy generation inside spherical capsule is analyzed. It is found that the entropy generation increases with increasing sphere capsule diameter, attains a maximum and then decreases. Keywords: Entropy generation, Phase change material, Solidification, Spherical capsule