Insight Into Recompression Brayton Cycle

Recompression cycles have the potential to offer high performance when design parameterssuch as feasibility, performance, and compactness are considered. These cycles haverecently gained attention especially in nuclear and concentrating solar power plantsbecause of their high efficiency and environmentally friendly. A study has been done toinvestigate and learn more about recompression cycles. In this paper, a recompressionBrayton cycle has been analyzed by performing parametric studies on the effectiveness ofrecuperators, pressure ratio, and split ratio as well as other input variables. To understandthe relations between these factors and the performances of the cycle, argon was used as aworkingfluid because of its constant specific heat. The solution to temperatures at eachstate has been derived analytically, which is presented as a function of independent inputvariables. Thermal efficiency and exergy efficiency of this cycle have been determined inthese analyses. The model indicates following results: entropy generation of recuperatorsis lower at a minimum split and decreases with increasing effectiveness. When the cycleis optimized for maximum efficiency it does not operate on maximum specific net work.The energy and exergy efficiencies of the cycle increase with increasing pressure ratioreaching a maximum value at the optimum pressure ratio. The effect of split ratio on tem-perature difference around recuperators shows that energy recovered at low temperature ishigher at a minimum split which yields a higher efficiency in the cycle. The performance ofthe cycle is strongly affected by turbine inlet temperature.