Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.
Condensation processes inside tubes are widely used in air
conditioning and refrigeration industry, since they promote an
improvement of the heat transfer, reducing the equipment size.
The distribution of the liquid and vapour phases inside the
tubes is crucial in the heat transfer process. Several studies have
been carried out for flow regime maps and flow regime
prediction techniques, in order to predict which flow pattern is
expected according to parameters such as the geometry of the
tubes, the flow rate and refrigerant properties. In this work, an
experimental research was conducted to obtain different
condensation flow patterns inside an 8 mm inner diameter
smooth copper tube. Experiments were carried out for mass
fluxes of 100, 200, 300, 400 and 600 kg/m2s, a saturation
temperature of 40 ºC and varying the vapour quality from 0.20
to 0.80 at 0.15 intervals. Experimental photographs and videos
are presented, discussed and compared against the results
provided by some flow pattern maps and prediction techniques
found in the literature.