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During the course of recent studies on wings at low Reynold number, it was observed that wing corrugation is often assumed to play an important role as well. However, studies show that corrugation of the wing is intended for structural purposes, and not aerodynamics. Corrugated wings have the advantage of being light and sturdy. Therefore, the main aim of this study is to understand the flow behaviour of the corrugated insect-scale wing; by conducting, a geometric parametric study during a non-oscillatory flight at a particular low Reynolds number and at two different angles of attack. In this computational study, a 3-D section of the corrugated wing along the chord is considered. The lattice Boltzmann method offers an alternative framework compared to the Navier-Stokes simulations. An open-source Parallel Lattice Boltzmann Solver on a high-performance computing platform is used for this computational analysis. The present study shows that the flow-related performance of the corrugated wing in terms of forces and kinetic energy is predominantly governed by the geometric variations that can largely affect the formation of vortices and their mutual interaction. The study reveals that the presence of corrugation does not affect the enhancement of forces and corrugation near the leading edge generally affects the performance due to large flow separation affecting the suction.

Advances in today's technology have led to the use of composite materials with their advantages of significant high strength with lightweight structure in aircraft design worldwide. With the aid of simulation, ANSYS, two main common problems in designing the aircraft composite wing, which is the aerodynamic loading on the wing and composite modeling; whereby both can be coupled to solve the aforementioned problems. The paper addresses with the use of fluid Structure Interaction (FSI) simulation and developed a standard numerical approach by integrating the aerodynamic loading from fluid domain with Finite Element (FE) analysis from structural domain in the application of hybrid composite laminates of aircraft wing structure. In this study, the Computational Fluid Dynamics (CFD) is conducted on the selected wing model of Selig 1223 in order to obtain the pressure loading from fluid domain before transferring it as an input to FE composite of structural domain. The FSI simulation was performed for two parametric conditions, namely Composite Wing Skin without Honeycomb (CWS) and Composite Wing skin with Honeycomb (CWSwH). From the result, CWSwH has lower total deformation with 3.06% percentage difference compared to CWS. However, the shear stress and strain values of CWSwH showed higher value than those of CWS due to the effect of the elasticity of honeycomb core. Therefore, the numerical approach of FSI with the application composite material has proven to be feasible and significant of current research on the behavior of fluid flow and structural for the wing skin, which replicates the real conditions of the aircraft wing during take-off or cruise. [ABSTRACT FROM AUTHOR]

Objective: The nasal cavity effectively captures the particles present in inhaled air, thereby preventing harmful and toxic pollutants from reaching the lungs. This filtering ability of the nasal cavity can be effectively utilized for targeted nasal drug delivery applications. This study aims to understand the particle deposition patterns in three age groups: neonate, infant, and adult. Materials and methods: The CT scans are built using MIMICS 21.0, followed by CATIA V6 to generate a patient-specific airway model. Fluid flow is simulated using ANSYS FLUENT 2021 R2. Spherical monodisperse microparticles ranging from 2 to 60 µm and a density of 1100 kg/m3 are simulated at steady-state and sedentary inspiration conditions. Results: The highest nasal valve depositions for the neonate are 25% for 20 µm, for infants, 10% for 50 µm, 15% for adults, and 15% for 15 µm. At mid nasal region, deposition of 15% for 20 µm is observed for infant and 8% for neonate and adult nasal cavities at a particle size of 10 and 20 µm, respectively. The highest particle deposition at the olfactory region is about 2.7% for the adult nasal cavity for 20 µm, and it is <1% for neonate and infant nasal cavities. Discussion and conclusions: The study of preferred nasal depositions during natural sedentary breathing conditions is utilized to determine the size that allows medication particles to be targeted to specific nose regions. [ABSTRACT FROM AUTHOR]

Background: The non-physiological structure of mechanical heart valves (MHVs) affects the blood flow field, especially the complex microstructure at the hinge. Numerous studies suggest that the blood flow field in the aortic area with an MHV can be considered Newtonian. However, the Newtonian assumption is occasionally unreasonable, where blood viscosity changes with shear rate, exhibiting non-Newtonian shear-thinning characteristics. Methods: In this research, a comprehensive study of the non-Newtonian effects on the hemodynamic behavior of MHVs was performed. The impact of the Newtonian hypothesis was investigated on the internal hemodynamics of MHVs. Several non-Newtonian and Newtonian models were used to analyze the chamber flow and blood viscosity. MHVs were modeled and placed in simplified arteries. After the unstructured mesh was generated, a simulation was performed in OpenFOAM to analyze its hemodynamic parameters. Results: In the study of the non-Newtonian viscosity model, the Casson model differs significantly from the Newtonian model, resulting in a 70.34% higher wall shear stress. In the modified Cross and Carreau models, the non-Newtonian behavior can significantly simulate blood in the MHV at different stages during initial and intermediate deceleration. The narrowing of the hinge region in particular, has a significant impact on evaluating blood rheology. The low flow rate and high wall shear force at the hinge can cause blood cell accumulation and injury time, resulting in hemolytic thrombosis. Conclusion: The results exhibit that the Newtonian hypothesis underestimates the hemodynamics of MHVs, whose complex structure leads to increased recirculation, stagnation, and eddy current structure, and a reasonable choice of blood viscosity model may improve the result accuracy. Modfied Cross and Carreau viscosity models effectively exhibit the shear-thinning behavior in MHV blood simulations. [ABSTRACT FROM AUTHOR]