ABSTRACT

 In this research work, a 100MW gas turbine (GT) plant simulated with a retrofitted compressor and intercooler was optimized using the particle swarm optimization (PSO) method. Exergetic and exergoecoflomic analysis of the GT components was also evaluated. The performance parameters considered include exergy efficiency, exergy destruction, compressor and turbine isentropic efficiency, and turbine inlet temperature (TIT). The GT data were obtained from the plant log sheet at base and operational conditions. Simulation was performed to obtain temperature and pressure at different state points for the two case scenario. The cost exergy streams was also attained by means of exergoeconomic balances with respect to plant components to provide a platform for cost rate optimization. The PSO algorithm was applied on an objective function modelled as a function of GT operating parameters, which formed the decision variables. The latter was used to determine an optimum configuration for reduced plant performance. Accordingly, the results obtained indicate a reduction in the overall exergy destruction rate and its associated cost. The values were between 75.938 MW and 564.84 $/hour respectively. In addition, the optimized results with PSO shows a reduction of 27 % and 24.5 %, correspondently for exergy destruction and total cost of exergy stream. Great potential for cost savings in plant operation with intercooling was highlighted with reduction in overall exergoeconomic factor from 0.53 to 0.1 73 and 8 % increase in the exergetic efficiency. The result also show a cost reduction from 4060 $/hour to 3421 $/hour at optimum, with 20 particles and 70 iterations while keeping the decision variables within accepted thermodynamic limits. In conclusion, the intercooling improves the power output by 3.5 % and the PSO method was found a good tool for GT optimization.