Effect of Waffle Height on the Air-Side Performance of Wavy Fin-and-Tube Heat Exchangers under Dehumidifying Conditions

An experimental study was carried out to examine the effect of the waffle height on air-side performance of typical fin-and-tube heat exchangers under dehumidifying conditions. The waffle heights examined in the present study are 1.18 and 1.58 mm, respectively. A total of 12 samples of heat exchangers, including eight having wavy fin and four having plain fin configurations were tested. The test results indicated that the effect of waffle height on the heat transfer enhancement ratio, compared to the plain-fin counterpart, is pronounced only for smaller fin pitch and larger waffle height, while its effect on the pressure drop is very pronounced throughout the test range, and is almost two times higher than in dry conditions.