Effect of EHD on heat transfer enhancement during two-phase condensation of R-134a at high mass flux in a horizontal smooth tube

摘要: In this study, effect of electrohydrodynamic (EHD) on the condensation heat transfer enhancement and pressure drop pure R-134a are experimentally investigated. The test section is a 2.5 m long counterflow double tube exchanger with refrigerant flowing in inner cooling water annulus. made from smooth horizontal copper tubing 9.52 mm outer diameter. electrode stainless steel wire 1.47 runs performed at average saturated temperatures ranging between 40 60°C, mass flux 200 600 kg/m2 s, 10 20 kW/m2 applied voltage kV. For presence electrode, experimental results indicate that maximum ratio around 30% while increase about 25%.