Jet cooling enhancement on a heated flat surface with optimized staggered fins

Abstract

This paper investigates the influence of staggered fins configuration on the flow and heat transfer characteristics of a single impinging jet on a heated flat plate. A numerical study, utilizing the v²f model, was conducted across a broad range of jet Reynolds numbers (8000–40,000) and jet aspect ratios (z/d = 0.5–8). The optimal staggered fins design for maximizing heat transfer was identified through systematic variation of fin dimensions: number of rows (n), height, thickness, spacing, and pitch. The performance of the optimized staggered fins configuration was then compared to both flat plate and straight in-line fins arrangements to assess its efficacy. Additionally, an experimental facility was fabricated to validate the priority of using staggered fins in cooling the heated flat plates. The results revealed that the optimized staggered fins configuration, featuring five rows, height ratio (h/R) of 0.2, and thickness ratio (t/R) of 0.053, spacing ratio (S/R) of 0.048 and pitch ratio (p/R) of 0.30, allows better heat dissipation compared to the other arrangements. At a jet Reynolds number of 8000, a 13.87 % increase in average Nusselt number was observed compared to the flat plate, and a 9.67 % increase over straight in-line fins. This advantage becomes even more pronounced at a Reynolds number of 30,000, with enhancements of 27.36 % and 13.64 % over flat plate and straight in-line fins configurations, respectively.