Experimental Study of the Thermal Contact Resistance in Fin and Tube

Abstract

In this paper, experimental study has been done to show the effect of the Thermal Contact Resistance (1/hc) in fin and tube. Three types of fin-tube design Embedded, Welded and L-footed are used in the test. Vacuum chamber with dimensions (45 cm length, 35 cm height, and 15 cm width) has been used for testing the sample of fin-tube, that’s placed inside the vacuum chamber. Vacuum pump is used to provide surrounding approximate emptied from air. The sample of fin-tube consists of hot water tube and cold water tube, the fin is fitted between themes. The experimental results showed that the thermal contact resistance decreases as the heat supply (source) increase. And the thermal contact resistance decreases when temperature drop at interface contact surfaces decreases. The results obtained of (1/hc) are least for embedded type and greatest for L-footed type. The thermal contact resistance (1/hc) of L-footed finned tube is higher than the others, by (250%) than the Embedded fin- tube type, and by (160%) of welded fin-tube type.

Keywords

• thermal contact resistance
• nature contact at interface surface
• fin and tube