Contemporary Engineering Sciences, Vol. 11, 2018, no. 44, 2149 - 2156 HIKARI Ltd, www.m-hikari.com https://doi.org/10.12988/ces.2018.85220 Second Law Analysis of Supercritical   Partial Cooling Brayton Cycle with Recompression Moisés D. Herrera 1 , Edgardo Castro 2 , Jorge Duarte 3 , Guillermo E. Valencia 4 and Luis G. Obregón 5 1 Mechanical Engineer, Simulation, Automation and Process Control – DIMER Research Group, Universidad del Atlántico Carrera 30 Número 8 - 49, Puerto Colombia, Colombia 2 Mechanical Engineer, Simulation, Automation and Process Control – DIMER Research Group, Universidad del Atlántico Carrera 30 Número 8 - 49, Puerto Colombia, Colombia 3 Design of Mechanical and Robotic Systems for Industrial Production – DIMER Research Group, Universidad del Atlántico Carrera 30 Número 8 - 49, Puerto Colombia, Colombia 4 Mechanical Eng., Efficient Energy Management Research Group – Kaí Universidad del Atlántico, Carrera 30 Número 8 – 49 Puerto Colombia, Colombia 5 Sustainable Chemical and Biochemical Processes Research Group Universidad del Atlántico, Carrera 30 Número 8 – 49 Puerto Colombia, Colombia Copyright © 2018 Moisés D. Herrera et al. This article is distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium provided the original work is properly cited. Abstract In the present study, energetic and exergetic analyses and optimization of a supercritical  2 ( −  2 ) Partial Cooling with recompression (PC) cycle, using reheat and without this, have been performed to study the effect of operating parameters on the optimum pressure ratio, energetic and exergetic efficiencies and component irreversibilities. Optimization is carried out using a Particle Swarm Optimization (PSO) genetic algorithm, and optimum operating conditions based on maximum first law efficiencies are determined. The result shows that the thermal