Open Access

ARTICLE

Numerical Simulation of Turbulent Heat Transfer in Concentric Annular Pipes

Jinping Xu^1,2, Zhiyun Wang¹, Mo Yang^1,*

1 School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
2 School of Energy and Power Engineering, Northeast Electric Power University, Jilin, 132012, China

* Corresponding Author: Mo Yang. Email:

(This article belongs to the Special Issue: Advances in Heat and Mass Transfer: Integrating Numerical Methods with Artificial Intelligence, Machine Learning, and Data-Driven Approaches)

Frontiers in Heat and Mass Transfer 2025, 23(4), 1151-1163. https://doi.org/10.32604/fhmt.2025.067925

Received 16 May 2025; Accepted 14 July 2025; Issue published 29 August 2025

Abstract

In concentric annular pipes, the difference in curvature between the inner and outer wall surfaces creates significant variations in the heat transfer characteristics of the two surfaces. The simplifications of the Dittus-Boelter equation for circular pipes make it unsuitable for the complex flow induced by the geometry and heat transfer coupling effects in annular pipes. This prevents it from accurately predicting the turbulent heat transfer in concentric annular pipes. This paper used realizable κ–ε and low Reynolds number models to conduct numerical simulations of turbulent convective heat transfer in concentric annular pipes and circular pipes. The results indicated that the local heat transfer coefficient and Nusselt number of the inner wall surface of the annular pipe were both higher than those of the outer wall surface. The Darcy resistance coefficient decreased upon increasing the Reynolds number and increased with the inner diameter-to-outer diameter ratio. When using the equivalent diameter as the characteristic scale, the turbulent heat transfer correlation obtained from circular pipes produced significant errors when used to approximate the turbulent convective heat transfer in concentric annular pipes. This error was greater for the inner wall surface, especially when the inner and outer diameters were relatively small, as the Nusselt number error on the inner wall surface reached 60.62%. The error of the Nusselt number on the outer wall surface reached 19.51%.

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Keywords

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