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This study aims to perform three-dimensional numerical computations for blood flow through a double stenosed carotid artery. Pulsatile flow with Womersley number (Wo) of 4.65 and Reynolds number (Re) of 425, based on the diameter of normal artery and average velocity of inlet pulse, was considered.

Finite volume method based ANSYS Fluent 20.1 was used for solving the governing equations of three-dimensional, laminar, incompressible and non-Newtonian blood flow. A high-quality grid with sufficient refinement was generated using ICEM CFD 20.1. The time-averaged flow field was captured to investigate the effect of severity and eccentricity on the lumen flow characteristics.

The results show that an increase in interspacing between blockages brings shear layer instability within the region between two blockages. The velocity profile and wall shear stress distribution are found to be majorly influenced by eccentricity. On the other hand, their peak magnitude is found to be primarily influenced by severity. Results have also demonstrated that the presence of eccentricity in stenosis would assist in flow development.

Variation in severity and interspacing was considered with a provision of eccentricity equal to 10% of diameter. Eccentricity refers to the offset between the centreline of stenosis and the centreline of normal artery. For the two blockages, severity values of 40% and 60% based on diameter reduction were permuted, giving rise to four combinations. For each combination, three values of interspacing in the multiples of normal artery diameter (D), viz. 4D, 6D and 8D were considered.

The purpose of this paper is to study haemodynamic flow characteristics and entropy analysis in a bifurcated artery system subjected to stenosis, magnetohydrodynamic (MHD) flow and aneurysm conditions. The findings of this study offer significant insights into the intricate interplay encompassing electro-osmosis, MHD flow, microorganisms, Joule heating and the ternary hybrid nanofluid.

The governing equations are first non-dimensionalised, and subsequently, a coordinate transformation is used to regularise the irregular boundaries. The discretisation of the governing equations is accomplished by using the Crank–Nicolson scheme. Furthermore, the tri-diagonal matrix algorithm is applied to solve the resulting matrix arising from the discretisation.

The investigation reveals that the velocity profile experiences enhancement with an increase in the Debye–Hückel parameter, whereas the magnetic field parameter exhibits the opposite effect, reducing the velocity profile. A comparative study demonstrates the velocity distribution in Au-CuO hybrid nanofluid and Au-CuO-GO ternary hybrid nanofluid. The results indicate a notable enhancement in velocity for the ternary hybrid nanofluid compared to the hybrid nanofluids. Moreover, an increase in the Brinkmann number results in an augmentation in entropy generation.

This study investigates the flow characteristics and entropy analysis in a bifurcated artery system subjected to stenosis, MHD flow and aneurysm conditions. The governing equations are non-dimensionalised, and a coordinate transformation is applied to regularise the irregular boundaries. The Crank–Nicolson scheme is used to model blood flow in the presence of a ternary hybrid nanofluid (Au-CuO-GO/blood) within the arterial domain. The findings shed light on the complex interactions involving stenosis, MHD flow, aneurysms, Joule heating and the ternary hybrid nanofluid. The results indicate a decrease in the wall shear stress (WSS) profile with increasing stenosis size. The MHD effects are observed to influence the velocity distribution, as the velocity profile exhibits a declining nature with an increase in the Hartmann number. In addition, entropy generation increases with an enhancement in the Brinkmann number. This research contributes to understanding fluid dynamics and heat transfer mechanisms in bifurcated arteries, providing valuable insights for diagnosing and treating cardiovascular diseases.

The purpose of this study is to analyze the two-dimensional blood flow in the artery slant from the axis at an angle with mild stenosis under the joint effects of the electro-osmotic, magnetic field, chemical reaction and porosity using a new analytical method. In addition, the mathematical model presented by the researchers Tripathi and Sharma (2018c) was successfully developed by adding the effect of electro-osmosis and studying the impact of the new addition in the developed model on blood flow.

A new analytical method was used to find the analytical approximate solutions of two-dimensional blood flow in artery slant from the axis at an angle with mild stenosis. This technique is based on integrating the Akbari-Ganji and the homotopy perturbation methods.

The results of axial velocity, concentration, temperature and the wall shear stress for blood flow were analyzed in the cases of the absence and presence of electro-osmosis. Furthermore, in these two states of electro-osmosis, a contour plot was created to show the difference in the profile of velocity to the flow of blood when the magnetic field was increased and the altitude of stenosis was increased. The results showed that the new technique is effective and has high accuracy to determine the analytical approximate solutions of two-dimensional blood flow in artery slant from the axis at an angle with mild stenosis. The validity, utility and necessity of the new method were illustrated from the graphs of the new solutions; in addition, there is an excellent agreement with the results of previous studies.

This paper focuses on developing the mathematical model which was presented by the researchers Tripathi and Sharma (2018c), by adding the effect of the electro-osmosis to it, which has been successfully developed. According to the authors’ modest information, the new system has not been studied before. This current problem is solved by using an innovative approach known as the Akbari-Ganji homotopy perturbation method (AGHPM) which has not been used before in two cases: the presence and absence of the effect of electro-osmosis. This new technique afford new with effective and has high accuracy results. Furthermore, the new study (i.e. adding effect of electro-osmosis) with the applications of (variable viscosity, magnetic field, chemical reaction and porosity) illustrated the importance of applying electro-osmosis and how doctors can benefit from it during surgeries through proper use.

Atherosclerosis tends to occur in the distinctive carotid sinus, leading to vascular stenosis and then causing death. The purpose of this paper is to investigate the effect of sinus sizes, positions and hematocrit on blood flow dynamics and heat transfer by different numerical approaches.

The fluid flow and heat transfer in the carotid artery with three different sinus sizes, three different sinus locations and four different hematocrits are studied by both computational fluid dynamics (CFD) and fluid-structure interaction (FSI) methods. An ideal geometric model and temperature-dependent non-Newtonian viscosity are adopted, while the wall heat flux concerning convection, radiation and evaporation is used.

With increasing sinus size, the average velocity and temperature of the blood fluid decrease, and the area of time average wall shear stress (TAWSS)with small values decreases. As the distances between sinuses and bifurcation points increase, the average temperature and the maximum TAWSS decrease. Atherosclerosis is more likely to develop when the sinuses are enlarged, when the sinuses are far from bifurcation points, or when the hematocrit is relatively large or small. The probability of thrombosis forming and developing becomes larger when the sinus becomes larger and the hematocrit is small enough. The movement of the arterial wall obviously reduces the velocity of blood flow, blood temperature and WSS. This study also suggests that the elastic role of arterial walls cannot be ignored.

The hemodynamics of the internal carotid artery sinus in a carotid artery with a bifurcation structure have been investigated thoroughly, on which the impacts of many factors have been considered, including the non-Newtonian behavior of blood and empirical boundary conditions. The results when the FSI is considered and absent are compared.

The development of new advanced materials, such as photopolymerizable resins for use in stereolithography (SLA) and Ti6Al4V manufacture via selective laser melting (SLM) processes, have gained significant attention in recent years. Their accuracy, multi-material capability and application in novel fields, such as implantology, biomedical, aviation and energy industries, underscore the growing importance of these materials. The purpose of this study is oriented toward the application of new advanced materials in stent manufacturing realized by 3D printing technologies.

The methodology for designing personalized medical devices, implies computed tomography (CT) or magnetic resonance (MR) techniques. By realizing segmentation, reverse engineering and deriving a 3D model of a blood vessel, a subsequent stent design is achieved. The tessellation process and 3D printing methods can then be used to produce these parts. In this context, the SLA technology, in close correlation with the new types of developed resins, has brought significant evolution, as demonstrated through the analyses that are realized in the research presented in this study. This study undertakes a comprehensive approach, establishing experimentally the characteristics of two new types of photopolymerizable resins (both undoped and doped with micro-ceramic powders), remarking their great accuracy for 3D modeling in die-casting techniques, especially in the production process of customized stents.

A series of analyses were conducted, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, mapping and roughness tests. Additionally, the structural integrity and molecular bonding of these resins were assessed by Fourier-transform infrared spectroscopy–attenuated total reflectance analysis. The research also explored the possibilities of using metallic alloys for producing the stents, comparing the direct manufacturing methods of stents’ struts by SLM technology using Ti6Al4V with stent models made from photopolymerizable resins using SLA. Furthermore, computer-aided engineering (CAE) simulations for two different stent struts were carried out, providing insights into the potential of using these materials and methods for realizing the production of stents.

This study covers advancements in materials and additive manufacturing methods but also approaches the use of CAE analysis, introducing in this way novel elements to the domain of customized stent manufacturing. The emerging applications of these resins, along with metallic alloys and 3D printing technologies, have brought significant contributions to the biomedical domain, as emphasized in this study. This study concludes by highlighting the current challenges and future research directions in the use of photopolymerizable resins and biocompatible metallic alloys, while also emphasizing the integration of artificial intelligence in the design process of customized stents by taking into consideration the 3D printing technologies that are used for producing these stents.