| Title |
An Experimental Study on the Local and Overall Heat Transfer Characteristics of a Fin-Flat Tube Heat Exchanger |
| Keywords |
Fin-tube heat exchanger ; 핀-관 열교환기 ; Flat tube ; 납작관 ; Naphthalene sublimation technique ; 나프탈렌승화법 ; Vortex generator ; 와류발생기 ; Heat transfer enhancement ; 열전달촉진 |
| Abstract |
Local and overall heat transfer characteristics of fin-flat tube heat exchangers with and without vortex generators are investigated. Local heat transfer coefficients are measured with the heat exchanger model using naphthalene sublimation technique. In case of a fin-flat tube heat exchanger without vortex generators, only the horseshoe vortices formed around tubes augment the heat transfer. On the other hand, longitudinal vortices created artificially by vortex generators enhance heat transfer dramatically in case of a fin-flat tube heat exchanger with vortex generators. Overall heat transfer coefficients are measured with the prototype of the fin-flat tube heat exchanger with and without vortex generators in a wind tunnel and results are compared with those of a fin-circular tube heat exchanger with wavy fin. Friction losses for heat exchangers are also measured and compared. The fin-flat tube heat exchanger with vortex generators is found to be more effective than the fin-circular tube heat exchanger with wavy fin. |