Effect of elliptical winglet on the air-side performance of fin-and-tube heat exchanger

• Published in: International journal of heat and mass transfer Vol. 123; pp. 583 - 599
• Main Authors: Chimres, Nares, Wang, Chi-Chuan, Wongwises, Somchai
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.2018; Elsevier BV
• Subjects: CFD; Elliptical winglet; Fin and tube heat exchanger; Fluid dynamics; Heat exchangers; Heat transfer; Heat transfer coefficients; Heat transfer enhancement; Pressure; Tube heat exchangers; Vortex generator; Vortices; Winglets; Heat transfer enhancement; CFD; Vortex generator; Fin and tube heat exchanger; Elliptical winglet
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2018.02.079

•The study of thermal performance of fin with elliptical winglet is presented.•The 3D-numerical evaluations of the fin with elliptical winglet are proposed.•Attack angle of elliptical winglet is the most impacts on the thermal performance.•The optimum designs of parameters for the elliptical winglet are reported.•CFD images inside the flow channel between fins are presented. This study numerically examines the elliptical winglets (EW) on the overall performance of fin-and-tube heat exchanger. The major geometrical parameters characterizing the EW has been investigated thoroughly, including the winglet location, attack angle and the trailing angle of the elliptical winglets with two different winglet lengths which are 1.0 mm and 1.5 mm. The numerical results indicate that the elliptical winglets with the 30° attack angle, 0 mm horizontal distance, 6 mm vertical distance and 120° trailing angle of both winglet lengths shows the highest performance. The heat transfer coefficients and pressure drops obtained by both winglet sizes are larger than that of the plain fin by about 13% and 35%, respectively. In term of the performance efficiency index, the 1.5 mm winglet length indicates about 1.8–2.9% improvement relative to plain fin geometry and the efficiency index of 1.0 mm winglet length is comparable with that of the plain fin.