Danışmaz, MerdinAkdağ, Ünal2025-07-182025-07-18202510407782https://dx.doi.org/10.1080/10407782.2025.2525315https://hdl.handle.net/20.500.12451/13389This study focuses on investigating the thermal performance of elliptical tubes in heat transfer applications with three different working fluids, namely water, CuO-water nano fluid, and Al2O3-water nano fluid. The research emphasizes the role of channel cross-sectional geometry and the utilization of nano fluids in enhancing heat transfer for four different elliptical aspect ratios with the same hydraulic diameter. To ensure fully developed hydrodynamic flow conditions and eliminate pipe outlet effects, a test section for flow analysis was identified at the midsection of the designed pipe geometry. Numerical simulations were conducted using ANSYS 2020 R2 commercial software for low Reynolds numbers, which yield laminar flow, to analyze the impact of the elliptical cross-sectional geometry and heat transfer characteristics on the flow. The effects of nano fluids and the use of elliptical pipes on heat transfer were validated against empirical formulas based on Nusselt numbers. The results indicate that nano fluids exhibit superior heat transfer performance compared to water across all elliptical aspect ratios investigated. Although the best thermal performance belongs to the CuO nanoparticle fluid, it was understood that the use of Al2O3 fluid would also be beneficial due to its accessibility and being more economical. Moreover, it was determined that increasing the ellipticity under the specified flow conditions improved the heat transfer efficiency. Overall, this research provides a comprehensive analysis of the interaction between channel geometry, nano fluid selection, and heat transfer performance, offering valuable insights for designing more effective heat transfer systems in various engineering applications.eninfo:eu-repo/semantics/closedAccessElliptical Pipe FlowFluid Flow in A ChannelLaminar FlowNano Fluid FlowArticle10.1080/10407782.2025.2525315105009478169WOS:001518367900001Q2