Experimental study of thermohydraulic characteristics and irreversibility analysis of novel axial corrugated tube with spring tape inserts

• Published in: European physical journal. Applied physics Vol. 92; no. 3; p. 30901
• Main Authors: Bhattacharyya, Suvanjan, Sarkar, Debraj, Mahabaleshwar, Ulavathi Shettar, Soni, Manoj K., Mohanraj, M.
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences 01.12.2020
• Subjects: Aerodynamics; Corrugation; Finite volume method; Fluid dynamics; Fluid flow; Friction; Friction factor; Heat exchanger tubes; Heat transfer; Inserts; Numerical analysis; Reynolds number; Swirling; Turbulence models; Working fluids
• ISSN: 1286-0042; 1286-0050
• DOI: 10.1051/epjap/2020200192

The current study experimentally investigates the heat transfer augmentation on the novel axial corrugated heat exchanger tube in which the spring tape is introduced. Air ( Pr  = 0.707) is used as a working fluid. In order to augment the thermohydraulic performance, a corrugated tube with inserts is offered. The experimental study is further extended by varying the important parameters like spring ratio ( y  = 1.5, 2.0, 2.5) and Reynolds number ( Re  = 10 000–52 000). The angular pitch between the two neighboring corrugations and the angle of the corrugation is kept constant through the experiments at β  = 120 0 and α  = 60 0 respectively, while two different corrugations heights ( h ) are analyzed. While increasing the corrugation height and decreasing the spring ratio, the impact of the swirling effect improves the thermal performance of the system. The maximum thermal performance is obtained when the corrugation height is h  = 0.2 and spring ratio y  = 1.5. Eventually, correlations for predicting friction factor ( f ) and Nusselt number ( Nu ) are developed.