Condensation heat transfer of a pure fluid and binary mixture outside a bundle of smooth horizontal tubes. Comparison of experimental results and a classical model

Condensation of R-134a on horizontal integral-fin titanium tubes

“…Gstoehl and Thome [9] reported a mean deviation of 2.2% of their own experimental data under the Nusselt predictions for the condensation of R-134a at 31 ºC saturation temperature on plain tubes with 18.91 mm outer diameter. These authors also discussed the discrepancies found by Belghazi et al [5] and Kumar et al [6,8] in the paper. The results aforementioned support the reliability of the experimental facility and the experimental data since the deviations from the Nusselt model are within the ranges reported by other authors.…”

“…Belghazi et al [5] reported a mean deviation of +5% between their experimental data and the Nusselt predictions for condensation of R-134a at 40 ºC saturation temperature on a tube with 16.8 mm outer diameter. Kumar et al [6,8] reported that the Nusselt model over predicted their experimental data for the condensation of R-134a at 40 ºC saturation temperature on a tube with 23.6 mm outer diameter with an average value of -15%.…”

“…Generally, these tubes are made of copper or copper-nickel alloys. The condensation heat transfer of HFC-134a on plain and different types of enhanced tubes is reported in several papers, Jung et al [2], Honda et al [3,4], Belghazi et al [5], Kumar et al [6][7][8], Gstoehl and Thome [9], Zhang et al [10] or Kang et al [1].…”

Experimental study of dropwise condensation on plasma-ion implanted stainless steel tubes

“…(11), it is assumed that the condensate flow forms a continuous film on the bottom part of the tube. This part of the tube is then associated with an infinite thermal resistance resulting in a decrease in the average heat transfer coefficient [12]. Visual observations inside the condenser cell have shown that at lower subcooling the condensate film does not cover the whole surface of the tube.…”

“…evaporator feed water pump, (7) water tank, (8) electric heater, (9) steam feed to the condenser, (10) condensate from the condenser tube, (11) condensate from the condenser shell, (12) venting, (13) condensate cooler, (14) condensate collection tank, (15) condensate pump, (16) level controller, (17) cooling water into the condenser, (18) cooling water out of the condenser, (19) cooling water into the plate heat exchanger, (20) cooling water out of the plate heat exchanger, (Ti) resistance thermometer Pt100-X, (Fi) flow meter, (mi) mass flow measurement.…”