Analysis of the recuperative gas turbine cycle with a recuperator located between turbines

A recuperative gas turbine cycle with a recuperator located between a high-pressure turbine and a low-pressure turbine (alternative recuperative cycle) is analyzed and compared with the simple cycle and conventional recuperative cycle in detail. The result based on the ideal cycle analysis shows that the alternative recuperative cycle can achieve the highest efficiency among the abovementioned three cycles, but its specific work is much lower. When all irreversible factors are taken into account, however, the alternative recuperative cycle does not exhibit the highest efficiency. Subsequently, this conclusion was confirmed by conventional numerical calculations of the three cycles. In addition, the influences of some important cycle parameters, including the temperature ratio, the pressure ratio, the heat transfer temperature difference, the pressure drop through the recuperator, and the temperature at the inlet of the recuperator, on the alternative recuperation are analyzed. The possible improvements in the alternative recuperative cycle efficiency by optimizing the pressure distribution between the turbines are proposed. Finally, an exergy analysis also is conducted to gain understanding of the loss distribution.