Thermo-Hydraulic Performance of Natural Convection in a Triangular Enclosure with a Vertically Displaced Heat Source

Abstract:

Natural convective in enclosures are very important topics in thermal engineering because they find versatile industrial applications. An internal circular cylinder's vertical position and heat source on fluid flow and heat transfer in a triangular cavity are investigated. Numerical simulations were carried out to analyze variations in the average Nusselt number, streamline topology, temperature distribution, and velocity fields by using ANSYS Fluent. The results show that the Nusselt number rises from approximately 0.91–0.94 at lower positions (Y = 0.1–0.3) to a maximum of about 0.97 near Y = 0.4 driven by intensified thermal gradients and buoyancy-induced circulation. Within the upper-to-mid region (Y = 0.2–0.4) the formation of large adjacent vortices enhances macro-scale mixing, resulting in nearly a 4% improvement in heat transfer relative to the reference case. At mid-level positions (Y = 0.4–0.6) quasi-steady symmetric circulations are sustained, maintaining effective convection with Nu values of 0.95–0.97. In contrast, at higher locations (Y = 0.7–0.9), the weakening of vortex strength leads to flow stagnation and localized deterioration in heat transfer, reducing Nu to about 0.90–0.92. Overall, the findings underscore the critical importance of internal component placement in improving natural cooling performance, and further suggest that the most efficient thermal behavior is achieved when the cylinder and heat source are positioned within 0.2 < Y < 0.4, offering practical guidance for optimizing the thermal design of triangular enclosures.

• Periodical: Advanced Engineering Forum (Volume 58)
• Pages: 69-80
• DOI: https://doi.org/10.4028/p-J5vgA5
• Online since: February 2026
• Authors: Farah Ibrahim Abdalsalam*, Ruslan Sabah Abdulrahman, Tahseen A. Jabbar, Safaa Hameed Faisal
• Keywords: Natural Convection, Nusselt Number, Rayleigh Number, Triangular Cavity

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