THERMAL SCIENCE

International Scientific Journal

Shuguang Li

,

Zhuoran Zhuang

,

Xiaoyi Ma

SIMULATION ON NATURAL CONVECTION OF CARREAU FLUIDS IN A LOCALLY HEATED TRAPEZOIDAL CAVITY

ABSTRACT
The laminar natural convection of non-Newtonian Carreau fluids in a trapezoidal cavity with a local heat source at the bottom is numerically investigated. A stabilized streamline-upwind/Petrov-Galerkin (SUPG) finite element algorithm is proposed, in which equal low-order finite elements are used. Effects of Rayleigh number (i.e., Ra = 104 and 105), power-law index (i.e., 0.6 ≤ n ≤ 1.4), Prandtl number (i.e., 0.1 ≤ Pr ≤ 100), and local heat source length (i.e., 0.1 ≤ η ≤ 1.0) are researched. Results show that for different power-law indexes, as Prandtl numbers increase, the convective heat transfer is enhanced; as power-law indexes increase, influences of Prandtl numbers decrease, as local heat source length increase, the convective heat transfer is enhanced.
KEYWORDS
Stabilized finite element, Carreau fluids, natural convection, trapezoidal cavity, Local heat source
PAPER SUBMITTED: 2025-06-01
PAPER REVISED: 2025-07-27
PAPER ACCEPTED: 2025-08-08
PUBLISHED ONLINE: 2025-09-13
DOI REFERENCE: https://doi.org/10.2298/TSCI250601160L
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2026, VOLUME 30, ISSUE No. 2, PAGES [1439 - 1451]
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Simulation on natural convection of Carreau fluids in a locally heated trapezoidal cavity

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