| Title |
The Effect of Water Contact Angles of the Fin Surfaces of the Fin-and-Tube Heat Exchangers on the Water Hold-up |
| Keywords |
Fin-and-tube heat exchanger ; 핀-관 열교환기 ; Surface characteristics ; 표면특성 ; Water hold-up ; 잔수량 ; Hydrophilicity ; 친수성 ; Contact angle ; 접촉각 ; Condensation ; 응축 |
| Abstract |
An experimental study on the behavior of the water hold-up by condensation of a fin-and-tube heat exchanger with regard to the surface characteristics, i.e., contact angles, was conducted. The static and dynamic contact angles were measured, and condensation experiments were conducted. Flow patterns on the fins with different surface characteristics were visualized. Results showed that the static contact angle is proportional to the dynamic contact angle within the range of this study. The water hold-up of the heat exchanger increases as the static or dynamic contact angle of its surfaces increases. Existence of transition of flow patterns was found as the static or dynamic angle increase. Due to the transition in the flow patterns, changes in the gradient of the water hold-up is occurred around the static angle of 80 . |