A Novel Vortex-Tube-Based Combined Cycle for Simultaneous Power and Cooling Production

Abstract In this work, a vortex tube is integrated to a combined cooling and power cycle. The vortex tube is a passive thermofluidic device that induces thermal energy separation in a compressed gas stream, producing two outlet flows at substantially different temperatures. The phenomenon occurs in the absence of moving components and is governed by complex turbulent swirling flow, pressure gradients, and viscous dissipation. The internal flow structure facilitates the redistribution of kinetic and thermal energy, leading to concurrent temperature rise in the peripheral region and cooling in the core region. The combined cycle is simulated by using carbon dioxide as the working fluid. A parametric study is conducted to examine the effects of vortex tube inlet pressure, vortex tube inlet temperature, and vortex tube internal pressure on the net power output, cooling capacity, combined performance factor (CPF), and exergetic efficiency. In addition, a normalized sensitivity analysis is performed to identify the most influential parameters. The results show that vortex tube inlet pressure and temperature strongly affect system performance, whereas the internal pressure has a relatively minor impact within the investigated range. Under optimal operating conditions, the system delivers 367 kW of net power, 561.5 kW of cooling capacity, a CPF of 18.70%, and an exergetic efficiency of 9.929%. The proposed configuration demonstrates strong potential for efficient and low-emission energy.