Thermal Performance Assessment of a Tubular Heat Exchanger Fitted with Flower Baffles

Abstract

This paper presents a numerical study of the hydrothermal air-side performance of a tubular heat exchanger fitted with flower baffles (FBs). The investigation was done by testing in-line and staggered FB arrangements for various baffles’ pitch ratios (, 1.5, 2, 2.5, and 3) with Reynolds number Re ranging from 3000 to 15,000. The results indicate that the use of the leads to stirring the stagnated zones downstream of the baffles, and improving the air mixture close to the tube walls, which, by consequence, presents an efficient solution to improve the thermal transfer coefficients. Also, the PR rise with a fixed blockage ratio of 0.5 leads to an increase of both the Nusselt number and friction factor values. The highest thermal performance factor η of 1.77 is achieved by using the in-line baffle arrangement at , , and . Finally, and for other useful applications, reliable correlations have been developed to predict Nusselt number and friction factor.