MHD free convection-radiation interaction in a porous medium - part I : numerical investigation

A numerical investigation of two dimensional steady magnetohydrodynamics heat and mass transfer by laminar free convection from a radiative horizontal circular cylinder in a non-Darcy porous medium is presented by taking into account the Soret/Dufour effects. The boundary layer conservation equations, which are parabolic in nature, are normalized into non-similar form and then solved numerically with the well-tested, efficient, implicit, stable Keller–Box finite-difference scheme. We use simple central difference derivatives and averages at the mid points of net rectangles to get finite difference equations with a second order truncation error. We have conducted a grid sensitivity and time calculation of the solution execution. Numerical results are obtained for the velocity, temperature and concentration distributions, as well as the local skin friction, Nusselt number and Sherwood number for several values of the parameters. The dependency of the thermophysical properties has been discussed on the parameters and shown graphically. The Darcy number accelerates the flow due to a corresponding rise in permeability of the regime and concomitant decrease in Darcian impedance. A comparative study between the previously published and present results in a limiting sense is found in an excellent agreement

Chemical reaction on heat and mass transfer flow past a vertical cylinder embedded in non-Darcy porous medium

An unsteady two dimensional free convection flow of a viscous incompressible fluid past an impulsively started semi-infinite vertical cylinder adjacent to a non-Darcian porous media in the presence of chemical reaction of first order is investigated. The governing boundary layer equations are formulated with appropriate boundary conditions and are solved using an implicit finite-difference method of Crank-Nicholson type. The problem is shown to be controlled by seven thermophysical and hydrodynamic dimensionless parameters, namely thermal Grashof number (Gr), species Grashof number (Gm), Darcy number (Da i.e. permeability parameter), Forchheimer number (Fs i.e. second order inertial porous parameter), Prandtl number (Pr), Schmidt number (Sc) and chemical reaction parameter (K1).The effects of thermophysical parameter on the transient dimensionless velocity, temperature and concentration are illustrated graphically. Also, the effects of the various thermo-physical parameters on the Skin friction, Nusselt number and Sherwood number are presented and discussed. This model finds applications in polymer production, manufacturing of ceramics or glassware and food processing

Computational modelling of magnetohydrodynamic convection from a rotating cone in orthotropic darcian porous media

Free convective magnetohydrodynamic flow from a spinning vertical cone to an orthotropic Darcian porous medium under a transverse magnetic field is studied. The non-dimensionalized two-point boundary value problem is solved numerically using the Keller-Box implicit finite difference method. The effects of spin parameter, orthotropic permeability functions, Prandtl number and hydromagnetic number on flow characteristics are presented graphically. Tangential velocity and swirl velocity are accentuated with increasing permeability owing to a corresponding decrease in porous media resistance. Temperatures are depressed with increasing permeability. Validation of the solutions is achieved with earlier studies. Applications of the study arise in electromagnetic spin coating materials processing

PLANTAR FASCIITIS TREATMENT WITH PLATELET-RICH PLASMA INJECTION VERSUS STEROID INJECTION

Objective: Plantar fasciitis is characterized by heel pain that worsens when you bear weight after a long period of rest. Injections of steroids are one of the numerous therapeutic techniques that are frequently used to control plantar fasciitis. Numerous studies demonstrate that short-term pain alleviation with steroid injections is not long-lasting. According to recent studies, autologous platelet-rich plasma (PRP) injections encourage healing, which improves both short- and long-term pain alleviation. To compare the effects of local PRP injection and corticosteroid in the management of chronic plantar fasciitis, the current study was conducted. Methods: Sixty patients who met the criteria for this prospective double-blind trial were randomly assigned to one of two groups. Patients in Group I received an injection of steroid, whereas those in Group II received an injection of PRPs. The PNS numerical pain score (NPS) and a visual analog scale (VAS) were used to evaluate the patients. An evaluation was conducted before the injection as well as at 6 weeks, 3 months, and 6 months after the injection. Results: The mean VAS in Group I reduced from 7.00 before injection to 2.31 and that in Group II decreased from 7.81 before injection to 1.12. At the 6-month follow-up, the mean NPS score in Group I increased from 7.05 to 1.41 and in Group II from 7.86 to 1.02. The VAS and NPS improvements were statistically significant. In both groups, the plantar fascia thickness had decreased at the conclusion of the 6-month follow-up period (5.88 mm in Group I to 4.03 mm and 5.96 mm to 3.27mm in Group II), and the difference was statistically significant. Conclusion: When compared to steroid injection, local PRP injection is an excellent therapeutic option for persistent plantar fasciitis with long-lasting positive effects

A Cross-sectional study on Out-of-Pocket expenditure towards Immunization and its consequences faced by families with under-five Children Residing at one of the Cities of Western India

Background: When immunization of under-five children results in Out-of-Pocket Expenditure (OOPE), it affects motivation of parents for vaccination inversely. Objectives: To assess determinants affecting preference for specific/mixed type of health facilities and to estimate out-of-pocket expenditure towards immunization of under-five children. To assess opinion of participants for prevention/decreasing OOPE towards immunization. Methods: A community-based cross-sectional study was conducted at one of zones of Ahmedabad city, selected by simple random sampling. Following technique of “30×7 cluster survey” with necessary house-hold information received from Municipal Corporation, selection of 7 children was pursued from each cluster reaching to sample-size of 210 (30 X 7). Results: Of 211 children included in study, 124(58.77%), 68(32.23%) and 19(9%) had taken immunization services from government, private and mixed variety respectively. Majority of families (110, 88.71%) preferring government healthcare-facility for immunization incurred expenses <5000 INR/child as while in other two groups, all beneficiaries had expensed>5000 INR/child. Conclusions: Determinants like child’s gender, parents’ education, Type of family, Socio-economic status, delivery place of child and occupation of father had statistically significant association with preferred place of vaccination. Fixation of upper ceiling-limit of vaccines which are recommended by pediatricians but not covered in government run program was one of suggestions

MHD free convection-radiation interaction in a porous medium - part II : Soret/Dufour effects

This paper is focused on the study of two dimensional steady magnetohydrodynamics heat and mass transfer by laminar free convection from a radiative horizontal circular cylinder in a nonDarcy porous medium by taking account the Soret/Dufour effects. The boundary layer equations, which are parabolic in nature, are normalized into non-similar form and then solved numerically with the well-tested, efficient, implicit, stable Keller–Box finite-difference scheme. Numerical results obtained for the velocity, temperature and concentration distributions, as well as the local skin friction, Nusselt number and Sherwood number for several values of the parameters, namely the buoyancy ratio parameter, Prandtl number, Forchheimer number, magnetohydrodynamic body force parameter, Soret and Dufour numbers. The dependency of the thermophysical properties has been discussed on the parameters and showed graphically. Increasing Forchheimer inertial drag parameter reduces velocity but elevates temperature and concentration. Increasing Soret number and simultaneously reducing Dufour number greatly boosts the local heat transfer rate at the cylinder surface. A comparative study between the previous published and present results in a limiting sense is found in an excellent agreement

Computational simulations of hybrid mediated nano-hemodynamics (ag-au/blood) through an irregular symmetric stenosis

This article examines theoretically and numerically the unsteady two-dimensional blood flow through a diseased artery featuring an irregular stenosis. An appropriate geometric model is adopted to simulate the irregular stenotic artery. Inspired by drug delivery applications for blood vessels, the impact of hybrid nanoparticles on blood flow using a modified Tiwari-Das model is discussed. The blood is examined to have a homogenous suspension of hybrid nanoparticles. Reynolds’ viscosity model is applied in the formulation to represent the temperature dependency of blood. The two-dimensional governing conservation equations for momentum and heat transfer with buoyancy effect are simplified by considering the mild stenotic approximation. A finite-difference technique is deployed to numerically discretize the transformed non-dimensional model. Extensive graphical results for blood flow characteristics are obtained by MATLAB code. Comprehensive visualization of the effects of hemodynamic, geometric and nanoscale parameters on transport characteristics is provided. The problem is conducted for silver and silver-gold hybrid mediated blood flow models, and experimental values of blood and these biocompatible metallic nanoparticles. A comparison between silver and hybrid nanofluid is obtained which promotes the use of hybrid nanoparticles in successfully achieving clinically more beneficial results associated with nano-drug delivery in diseased hemodynamics. Enhancement in viscosity parameter induces axial flow acceleration in the stenotic region while lower thermal conductivity decreases the temperature magnitudes. Furthermore, with time variation, the pressure gradient is found to be lower in coronary arteries comparatively to femoral arteries. The simulations are relevant to transport phenomenon in nano-drug targeted delivery in haematology