Numerical simulation study of heat transfer enhancement in a tube based on an eccentric structure

Abstract

Enhancing the heat transfer performance of heat exchangers is crucial for solving energy shortage and environmental pollution problems. Eccentric structure tube, with the advantages of small volume ratio, large heat transfer area, compact structure, and cleanliness, was used in this work to strengthen the heat transfer performance. A three-dimensional numerical simulation method was used to investigate the flow and heat transfer characteristics of the working medium in an eccentric tube under the laminar flow condition. The results display that the Nusselt (Nu) number, friction factor, and comprehensive performance evaluation coefficient (PEC) of the eccentric tube decreased with the increase of lead (s). With increasing eccentric distance, the Nu number and friction factor increased and the PEC first increased and then slightly decreased. At an s of 50 mm and eccentric distance of 4 mm, the PEC could reach 2.43.

Keywords

• Eccentric tube
• Heat transfer enhancement
• Longitudinal vortex
• Lead
• Eccentricity