Investigation on cooling the hot tube surfaces of vortex tube at different pressure and fraction with comprehensive thermal performance analysis

The Raque Hilsch Vortex Tube (RHVT) is a heat pump system that uses the phenomenon of compressed vortex airflow in a tube for cooling and heating. This study aims to determine the effect of pressure and fraction on RHVT by cooling the surface of the hot tube naturally and forcefully. Tube type testing was conducted with a pressure variation of 0.5–1.5 bar and a fraction of 30%–70%. The results of the analysis show that forced cooling on the surface of the hot tube decreases the heating performance (Th, ΔTh, Q˙h, ηish, and COPh) and improves the cooling performance (Tc, ΔTc, Q˙c, ηisc and COPref). The higher pressure increases the performance of Th ΔTh, Q˙h, Tc ΔTc, and Q˙c, and decrease the performance of ηish, COPh, ηisc, and COPref. The fraction 40% is the most optimal parameter for the performance of Tc ΔTc, Q˙c. The 60% fraction works best for Th, ΔTh, Q˙h, ηish, and COPh, while the fraction 70% works best for Q˙c and COPref. The most optimal performance values include Th (41 °C), ΔTh (14 °C), Q˙h (2.369kJ/s), ηish(24.21%), COPh (0.092), Tc (13.450 °C), ΔTc (13.550 °C), Q˙c (3.280kJ/s), ηisc (20.84%), and COPref (0.123).