Comprehensive correlations for heat transfer during condensation in conventional and mini/micro channels in all orientations

• Two correlations are presented for condensation heat transfer in plain channels.
• Excellent agreement with 4063 data points for 33 fluids from 67 sources.
• Include channels of many shapes, diameters 0.1 to 49 mm, all orientations.
• Data include pressures very low to near critical, flow 1.1 to 1400 kg m−2s−1.
• These are the only correlations applicable to all channel sizes and orientations.

Two alternative correlations are presented for heat transfer during condensation in plain conventional channels as well as mini/micro channels in all orientations. These have been validated by comparison with a database that includes 33 fluids, diameters 0.10 to 49.0 mm, reduced pressures 0.0008 to 0.946, mass flux from 1.1 to 1400 kgm−2s−1, various shapes (round, rectangular, triangular, etc.), all orientations (horizontal, vertical up and down, and angles in between). The data are from 136 data sets from 67 sources. While both correlations predict the 4063 data points with mean absolute deviation (MAD) of about 17%, their accuracy varies somewhat in different ranges. The same data are also compared to other correlations.