Improvement of thermal-hydraulic performance of compact heat exchangers with multi-corrugated fin and oval tube arrays

Abstract

Compact heat exchanger (CHXs) is one of the top choices in residential and industrial applications for its higher thermal efficiency, lower pressure drop, low cost, light weight characteristics. Among various types of compact thermal devices, fin and tube compact heat exchangers are stimulating enormous interest in thermal engineering field. In the present study, airside performance of CHXs having corrugated fin and oval tube are evaluated using a CFD code ANSYS 12.0. Main motivation of this investigation is to find out the pattern of gradual improvement of thermal-hydraulic performance by showing the comparison between plane and corrugated fin geometry. This study has been performed for Reynolds number ranging from 200 to 1000. Here we have analyzed the performance among plane, one, two & three corrugated fin geometry. Also, the variation of tube shape changing the circular tube geometry to oval shape has also been studied. The significant increase of Nusselt number, Friction factor, Colburn factor has been found for the corrugated compact heat exchangers. Results indicate that incurring a moderate pressure loss the corrugated fin patterns can ensure more thermal efficiency. The pattern of gradual improvement of heat transfer rate and slacken pressure loss with the increase of corrugation in a fin with oval shaped tubes have been experienced.