A comparative analysis of two mid-sized oxyfuel combustion combined cycles is performed. The two cycles are the semiclosed\noxyfuel combustion combined cycle (SCOC-CC) and the Graz cycle. In addition, a reference cycle was established as the basis for\nthe analysis of the oxyfuel combustion cycles. A parametric study was conducted where the pressure ratio and the turbine entry\ntemperature were varied.The layout and the design of the SCOC-CC are considerably simpler than the Graz cycle while it achieves\nthe same net efficiency as the Graz cycle. The fact that the efficiencies for the two cycles are close to identical differs from previously\nreported work. Earlier studies have reported around a 3%points advantage in efficiency for the Graz cycle, which is attributed to the\nuse of a second bottoming cycle. This additional feature is omitted to make the two cycles more comparable in terms of complexity.\nThe Graz cycle has substantially lower pressure ratio at the optimum efficiency and has much higher power density for the gas\nturbine than both the reference cycle and the SCOC-CC.
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