Abstract
The reheat and regenerative Braysson cycle being an alternative for combined cycle power plants needs to be optimized for its efficient utilization of energy resources. Therefore, to obtain the best possible overall pressure ratio, regenerator effectiveness and pressure ratio across multi-stage compression in order to simultaneously maximize exergy efficiency, non-dimensional power density and ecological coefficient of performance for three different maximum temperature situations, multi-objective optimization of the above cycle is carried out using Non-dominated sorting genetic algorithm-II (NSGA-II). The optimal solutions given by the Pareto frontier are further assessed through widely used decision makers namely LINMAP, TOPSIS and Bellman-Zadeh techniques. The optimal solutions attained by the decision making process are further evaluated for their deviation from the non-ideal and ideal solutions. The optimal solution obtained through TOPSIS possess the minimum deviation index. Finally the results are authenticated by performing an error analysis. Such optimal scenarios achieved for the three maximum temperatures are further analysed to achieve the final objective of the most optimal solution which happens to be at 1200K. The simultaneous optimization of performance parameters which reflect the thermo-ecological criteria to be satisfied by a power plant has resulted in values of 0.479, 0.327 & 0.922 for exergy efficiency, non-dimensional power density and ecological coefficient of performance respectively. These optimized performance parameters are obtained for an overall pressure ratio of 7.5, regenerator effectiveness of 0.947 and pressure ratio across multi-stage compression of 1.311.
Enhancing the Profitability of Solar Tower Power Plants through Thermoeconomic Analysis Based on Multi-objective Optimization