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This study explores the potential of hybrid nanofluids (HNFs) in enhancing the efficiency of thermal management systems, particularly in medical engineering applications where precise temperature control is critical. Motivated by the need for innovative and sustainable cooling solutions, this research examines the infusion of carbon nanostructures (CNS) into HNFs to improve thermal exchange performance. The study applies the non-Newtonian Maxwellian model and the Cattaneo–Christov thermal flow framework to simulate their behavior in specialized curved channels analogous to heat exchangers in medical devices such as imaging equipment or cryogenic systems. Hypothetical trials and computerized simulations evaluate the heat transfer rate and flow dynamics of nanotube-infused HNFs. Key factors, including heat radiation, fluid resistance, sliding velocity, and permeable substances, are assessed to determine efficiency improvements. By utilizing similarity transformation to simplify the governing partial differential equations (PDEs) and employing the finite element method (FEM) alongside Akbari–Ganji’s method (AGM) for precise solutions, the study highlights the potential of multi-layered carbon nanotube–single-layered carbon nanotube with engine oil mixed nanofluids to significantly enhance heat transfer. The findings demonstrate a 1.65% improvement in thermal performance, suggesting promising implications for advanced thermal management systems in medical devices and healthcare technologies.

In this paper, we prove the convergence of the numerical approximations of a scalar parabolic equation modeling a non-Newtonian fluid. We use finite-difference schemes and the well-known method of external approximations.

This paper is devoted to studying the well-posedness and optimal solution techniques for a full discretization scheme, proposed by Lee and Xu (2006), for a large class of viscoelastic flow models. By using some special properties of the scheme such that it is stable in the energy norm and it preserves the positivity of the conformation tensor, the global existence and uniqueness of the solution of the discrete scheme is established. Furthermore, it is shown that the solution of the discrete scheme at each time step can be obtained by an iterative procedure that only requires operations (with N being the number of nodes of the underlying finite element grid).

Hemodynamic factors such as velocity distribution, pressure gradient and wall shear stress are thought to play an important role in the prognosis of symptomatic carotid occlusion. Although there are many studies about modeling the blood flow behavior in carotid, hemodynamic characteristics of blood flow in a stenosed carotid artery is still debatable. In this study a three-dimensional (3D) model of a symmetric stenosed common carotid artery (CCA) is developed and the simulation results of it are compared to the experimental data where subsequent agreement is confirmed. To study the accuracy of two-dimensional (2D) axisymmetric model, the result of it is compared to the result of the 3D model. Two non-Newtonian rheological models, namely Carreau and modified Power-law, as well as Newtonian model are used to realize the hemodynamical differences of 2D-axisymmetric and 3D models in pulsatile blood flow. Comparing the 3D simulated results with 2D-axisymmetric modeling results that were published in recent years indicates that the assumption of 2D-axisymmetric model cannot adequately predict the velocity profiles even for a symmetric stenotic artery. Although a symmetric stenotic artery is considered, the results indicate a nonsymmetric flow in poststenosis region that is detected by the presence of extensive secondary flows particularly at diastole. The existence of secondary flows that can only be detected in 3D modeling is the main reason for the differences in hemodynamic factors in 3D and 2D results.