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1.
Sci Rep ; 14(1): 766, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38191791

ABSTRACT

Generation of fluid flow due to simultaneous occurrence of heat and mass diffusions caused by buoyancy differences is termed as double diffusion. Pervasive applications of such diffusion arise in numerous natural and scientific systems. This article investigates double diffusion in naturally convective flow of water-based fluid saturated in corrugated enclosure and containing hybrid nano particles composed of Copper (Cu) and Alumina (Al2O3). Impact of uniformly applied magnetic field is also accounted. To produce thermosolutal convective potential circular cylinder of constant radius is also adjusted by providing uniform temperature and concentration distributions. Finite element approach is capitalized to provide solution of utilized governing equations by utilizing Multiphysics COMSOL software. Wide-range of physical parameters are incorporated to depict their influence on associated distributions (velocity, temperature and concentration). Interesting physical quantities like Nusselt number, Sherwood numbers are also calculated against involved sundry parameters. It is note worthily observed that maximum strength of stream lines [Formula: see text] is 3.3 at [Formula: see text] and drops to 1.2 when [Formula: see text] is increased to 0.04. Furthermore, in the hydrodynamic case (Ha = 0), it is observed that the velocity field exhibits an increasing trend compared to the hydromagnetic case [Formula: see text] which is proved from the attained values of stream-function i.e., [Formula: see text] (in the absence of a magnetic field) and [Formula: see text] (in the presence of a magnetic field). It is revealed from the statistics of Nusselt number that increase in volume fraction of nano particles from 0 to 0.4, heat flux coefficient upsurges up to 7% approximately. Since, present work includes novel physical aspects of thermosolutal diffusion generated due to induction of hybrid nanoparticles in water contained in corrugated enclosure, so this study will provide innovative thought to the researchers to conduct research in this direction.

2.
Micromachines (Basel) ; 13(10)2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36295977

ABSTRACT

Convection in fluids produced by temperature and solute concentration differences is known as thermosolutal convection. It has valuable utilization in wide industrial and technological procedures such as electronic cooling, cleaning, and dying processes, oxidation of surface materials, storage components, heat exchangers, and thermal storage systems. In view of such prominent physical significance, focus is made to explicate double (thermal and solutal)-diffusive transport in viscoelastic fluid characterized by the Casson model enclosed in a curved enclosure with corrugations. An incliningly directed magnetic field is employed to the flow domain. A uniformly thermalized and concentrated circular cylinder is installed at the center of the enclosure to measure transport changes. Dimensionally balanced governing equations are formulated in 2D, representing governed phenomenon. Finite element-based open-sourced software known as COMSOL is utilized. The domain of the problem is distributed in the form of triangular and quadrilateral elements. Transport distributions are interpolated by linear and quadratic polynomials. The attained non-linear system is solved by a less time and computation cost consuming package known as PARDISO. Convergence tests for grid generation and validation of results are executed to assure credibility of work. The influence of involved physical parameters on concerned fields are revealed in graphical and tabular manner. Additionally, heat and mass fluxes, along with, kinetic energy variation are also evaluated.

3.
Sci Rep ; 12(1): 3342, 2022 02 28.
Article in English | MEDLINE | ID: mdl-35228602

ABSTRACT

The current communication is designed by keeping in the mind high heat transfer capabilities of nanoliquids with the dispersion of diversified-natured nanoparticles in poorly conducting base liquids. Here, an amalgamation of metallic (Cu) and hybridization of metallic and non-metallic oxide (Cu-TiO2) nanoparticles to uplift thermophysical attributes of water is deliberated. The magnetically affected flow between rotating disks under the impact and permeability aspect is assumed. Empirical relations for effective dynamic viscosity, density, and heat capacitance to show mesmerizing features of obliged nanoparticles are also expressed. In addition, mathematical relations also depend on morphological factors like shape, size, and diameter of inducted nanoparticles. The mathematical formulation of the problem is conceded in the form of a system of ODEs after using similarity transformation on dimensional PDEs. Simulations of the complex coupled differential structure are solved by using a numerical approach by employing shooting and Runge-Kutta procedures jointly. The impact of flow concerning variables on associated distributions is revealed through tabular and graphical manner. Quantities of engineering interest associated with work like wall friction and thermal flux coefficients at walls of the disk are also calculated. It is deduced from an examination that the addition of metallic particles raises heat transfer more than non-metallic particles. A significant impression of magnetic field on shear stress is executed by hybrid nanoparticles along the surface of disks. In addition, elevation in Nusselt number and depreciation in skin friction coefficient is revealed against increasing magnitude of nanoparticle volume fraction. A positive trend in skin friction coefficient is manifested against the increasing magnitude of Reynold number. It is also observed that by increasing the size and shape of hybrid nanoparticles thermal conductivity and viscosity of the base fluid increases.


Subject(s)
Nanoparticles , Friction , Hot Temperature , Nanoparticles/chemistry , Physical Phenomena , Thermal Conductivity
4.
Nanomaterials (Basel) ; 12(4)2022 Feb 17.
Article in English | MEDLINE | ID: mdl-35214999

ABSTRACT

Currently, pagination clearly explains the increase in the thermophysical attributes of viscous hybrid nanofluid flow by varying morphological aspects of inducted triadic magnetic nanoparticles between two coaxially rotating disks. Copper metallic nanoparticles are inserted with three different types of metallic oxide nanoparticles: Al2O3, Ti2O, and Fe3O4. Single-phase simulation has been designed for the triadic hybrid nanofluids flow. The achieved expressions are transmuted by the obliging transformation technique because of dimensionless ordinary differential equations (ODEs). Runge-Kutta in collaboration with shooting procedure are implemented to achieve the solution of ODEs. The consequences of pertinent variables on associated distributions and related quantities of physical interest are elaborated in detail. It is inferred from the analysis that Cu-Al2O3 metallic type hybrid nanofluids flow shows significant results as compared with the other hybrid nanoparticles. The injection phenomenon on hybrid nanofluids gives remarkable results regarding shear stress and heat flux with the induction of hybridized metallic nanoparticles. Shape and size factors have also been applied to physical quantities. The morphology of any hybrid nanoparticles is directly proportional to the thermal conductance of nanofluids. Peclet number has a significant effect on the temperature profile.

5.
J Ayub Med Coll Abbottabad ; 29(3): 412-414, 2017.
Article in English | MEDLINE | ID: mdl-29076672

ABSTRACT

BACKGROUND: Pigment Dispersion Syndrome (PDS) is an autosomal dominant disorder of white males between 20 to 40 years of age characterized by deposition of pigment on the lens, zonules of lens, trabecular meshwork and corneal endothelium (Krukenberg's spindle) in addition to radial, spoke like transillumination defects in the mid peripheral iris. This study was conducted to determine the frequency of occurrence of Pigmentary Glaucoma in patients with Pigment Dispersion Syndrome (PDS). METHODS: This longitudinal follow up study included patients presenting with Krukenberg's spindle on the endothelial side of cornea and pigmentation of angle of anterior chamber seen on slit lamp examination and gonioscopy. RESULTS: Seventy-two cases of PDS were included in the study, amongst them 63 (87.50%) were males. Mean age was 35.00±6.54 years (range 24-46 years). Forty-seven (65.28%) patients had an IOP in the range of 10-14 mmHg, 22 (30.56%) patients had an IOP in the range of 15-18 mmHg and 3 (4.17%) patients developed an IOP of greater than 19 mmHg. Fundoscopy showed myopic degeneration in 49 (68.06%) patients and optic disc cupping in 3 (4.17%) patients. Four (5.56%) patients had refractive error between +1D to +3D, 9 (12.50%) patients had refractive error between -1D to -4D, 21 (29.17%) patients had refractive error between -5 D to -8 D and 38 (52.78%) patients had refractive error between -9 D to -12 D. Our study showed that one patient having PDS developed glaucoma at 5 years of follow up and three patients developed glaucoma at 14 years of follow up. CONCLUSIONS: On the basis of this study we conclude that early onset primary open angle glaucoma associated with PDS or Juvenile glaucoma associated with PDS might have been mistaken as Pigmentary Glaucoma in Pakistani patients and a distinct entity in the form of Pigmentary Glaucoma may be non-existent.


Subject(s)
Glaucoma, Open-Angle/diagnosis , Adult , Female , Humans , Longitudinal Studies , Male , Middle Aged , Young Adult
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