Experimental Analysis of Heat Transfer and Friction Factor Characteristics in Turbulent Flow through a Tube Fitted with Screw Tape

The methods of augmentation heat transfer are widely utilized in many applications in the heating process to enable reduction in weight and size or increase the efficiency of heat exchangers. These methods are classified as passive, active and combination of (active & passive) these two techniques. For implementing active technique it is required external power such as electric or acoustic fields and surface vibration, whereas while adopting the passive techniques required special surface geometries, fluid additives, swirl/vortex flow devices, that is various types of tape inserts. The passive techniques are better the active techniques because the manufacturing process swirl formation inserts is simple and can be easily implemented in an existing heat exchanger. Moreover the passive techniques can play an important role in the intensification of heat transfer. According to working conditions a proper configuration of the insert is being selected .A Copper tube of 21 mm internal diameter and 25 mm outer diameter and 1000 mm test length was used. The heat transfer parameters was carried out by conducting an experimental study in tube with twisted tape and Screw tape with different diameters for Reynolds number range of 12,000 to 25000. The heat transfer coefficient, friction factor, Nusselt number, Thermal Performance Factor and enhancement efficiency of the twisted tape and Screw tape with different diameters have been obtained and compared with the plain tube. The comparisons showed that, compared with the twisted tape, the Screw tape with different diameters has further improved convective heat transfer performance by about 15 to 20 % and whereas lowered flow friction. The Screw tape with different diameters shows about 25% greater thermal performance than twisted tape at a cost of very low friction factor values. citation: Ganesh R. Ghodake, JSPM's Imperial College of Engineering & research, Wagholi Pune (M.S.); Dr. Rahulkumar S. Hingole, JSPM's Bhivrabai Sawant Institute of Technology and Research Wagholi; Dr. Kishore P. Kolhe ,JSPM's Imperial College of Engineering & research, Wagholi Pune (M.S.). "Experimental Analysis of Heat Transfer and Friction Factor Characteristics in Turbulent Flow through a Tube Fitted with Screw Tape ." Global Research and Development Journal For Engineering 17 2016: 112 - 121.