Heat transfer performance of internally finned tube

Abstract

Heat transfer performance of a T-seetion internal fin 111 a circular tube has been experimentally investigatcd. Thc T-seetinn linned tube was designed, fabricated and installed and was heatedclectrieally. The same was donc 1'01' a smooth tube in order to make comparison. Fully developed stcady state turbulent airflow acts as a heat sink in this study. Data were collected in the Reynolds number range "I' 2.0x I04 to 5.0x I04 for smooth tube and 2.2x 104 to 4.5x 104 for linned tube. Wall temperature. bulk fluid temperature, pressure drop along the axial distance of the finned and smooth tube were recorded for the above mentioned Reynolds number. From the measured data, heat transfer coefficient, Nusselt numher. Ii'ietion factor and pumping power variation were calculated and analyzed. Friction factor and pumping power arc substantially increased in the finned tube In comparison to the smooth tube. For linned tuhc, ii'iction factor is 3.0 to 4.0 times and pumping power is 3.5 to 4.5 times higher than those of smooth tube for the Reynolds numher range 2.0x I04 to 5.0x I04. Heat transfer coemcient for linned tuhe is about 1.5 to 2.0 times higher than that of smooth tubc in these Reynolds numbers. Higher heat transfer area may be one of the reasons for this hcat transfcr enhancement. The linned tube in this study produces significant heat transfer enhancement at the cost of increased pumping power.