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Direct Expansion plate finned tube coils (DX) are extensively used in air conditioning systems. If
the air flowing over the coil is humid and the coil temperature is below the dew point, condensation
will occur on the fins.
In this paper a two-row unit (DX) in which the tubes are arranged triangular, has been selected for analysis of sene sible and latent heats.By applying
a tow-dimensinal analysis on an individual cell of the coil, the governing equations have been
derived. These equations have been solved numerically using a finite difference method. The
temperature distribution and fin efficiency variation for both wet and dry surface conditions,
versus the fin pitch, fin material, temperature and humidity of the inlet air flow and Reynolds
number, have been determined.