Numerical Analysis of Tube Heat Exchanger with Perforated Star-Shaped Fins

• Main Authors: Mladen Bošnjaković, Simon Muhič
• Format: Article
• Language: English
• Published: MDPI AG 2020-12-01
• Series: Fluids
• Subjects: star-shaped fin; perforation; heat exchanger; extended surfaces
• Online Access: https://www.mdpi.com/2311-5521/5/4/242

This article discusses the possibility of further reducing the mass of the heat exchanger with stainless steel star-shaped fins while achieving good heat transfer performance. For this purpose, we perforated the fins with holes Ø2, Ø3, and Ø4 mm. Applying computational fluid dynamics (CFD) numerical analysis, we determined the influence of each perforation on the characteristics of the flow field in the liquid–gas type of heat exchanger and the heat transfer for the range of <i>Re</i> numbers from 2300 to 16,000. With a reduction in the mass of the fins to 17.65% (by Ø4 mm), perforated fins had greater heat transfer from 5.5% to 11.3% than fins without perforation. A comparison of perforated star-shaped fins with annular fins was also performed. Perforated fins had 51.8% less mass than annular fins, with an increase in heat transfer up to 26.5% in terms of Nusselt number.