Proposal and evaluation of two innovative combined gas turbine and ejector refrigeration cycles fueled by biogas: Thermodynamic and optimization analysis

Energy enhancement and utilization of renewable energy sources have become inevitable solutions for the concerns of fossil fuel depletion and global warming. Two different cogeneration systems are pro-posed for cooling and power generation. A gas turbine and an ejector refrigeration cycle are employed in the configurations, in which gas turbine cycle uses biogas as the required fuel. First, these two config-urations are analyzed from energy and exergy perspectives. A comprehensive parametric study is also performed by decision variables for the optimization. Results reveal that both energy and exergy effi-ciencies of conventional combined gas turbine/ejector refrigeration cycle can be improved up to 44.6% and 33.54%, respectively. Besides, the outcomes of the parametric study point out that the combustion chamber has a significant effect on energy and exergy efficiencies and can increased them about 10%. Also, it is found that the vapor generator accounts for the highest exergy destruction among all com-ponents. Moreover, by using a genetic algorithm as an optimization method, the thermal and exergetic efficiencies of the base system improves. In the best operating condition, the thermal and exergetic efficiencies of the system reach 57.11% and 36.68%, respectively. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study investigates energy enhancement and utilization through the use of a gas turbine and ejector refrigeration cycle. Comprehensive analysis and parametric study were conducted from energy and exergy perspectives. Results show significant improvements in energy and exergy efficiencies, indicating promising engineering applications.