| Title |
Friction and Heat Transfer Characteristics of Enhanced Tubes with Internal Ribs |
| Keywords |
거친 표면 ; roughened surface ; 마찰계수 ; friction factor ; 열전달계수 ; heat transfer coefficient ; 상사함수 ; similarity function |
| Abstract |
The objectives of this paper are to study the heat transfer characteristics on enhanced surfaces, to develop experimental correlations of friction factor and Nusselt number, and to provide a guideline for optimum operation conditions at low temperature boiling for practical refrigeration applications. The working fluid(water, EG 30%) flows inside the enhanced tube and R134a boils on the outer surface. Two different types of Turbo-B tubes (Tube I and Tube II) are tested in the present study. The results show that Tube I gives a higher heat transfer coefficient with higher friction factor than Tube II. The present study provided experimental correlations for friction factor and heat transfer coefficient with error bands of ±5% and ±15%, respectively. |