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1.
Sci Rep ; 14(1): 1520, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233448

RESUMO

Nanoparticles have numerous applications and are used frequently in different cooling, heating, treatment of cancer cells and manufacturing processes. The current investigation covers the utilization of tetra hybrid nanofluid (aluminum oxide, iron dioxide, titanium dioxide and copper) for Crossflow model over a vertical disk by considering the shape effects (bricks, cylindrical and platelet) of nanoparticles, electro-magneto-hydrodynamic effect and quadratic thermal radiation. In the current inspection model is first derived given PD-equations and then altered into a system of OD-equations by including similarity variables. The converted ordinary differential equations are solved by using the finite element procedure and the impact of the solution against numerous involved parameters is displayed through tables and graphs. It is observed that tetra-hybrid nanoparticles are recommended better in industrial applications where the highest production of thermal energy. Moreover, an enhancement of thermal production can be achieved utilizing different values of the magnetic parameter, time relaxation number, variable thermal radiation number and magnetic induction number but the opposite trend has been noticed with the effects of radiation number.

3.
Sci Rep ; 13(1): 15040, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699944

RESUMO

Transport of heat visualizes a vital role in many industrial developments. Current study is discussing the role of Joule heating, solar thermal radiation, heat generation/absorption, reactions (homogeneous and heterogeneous) with variable thermal conductivity on partially ionized power law material past over a three-dimensional heated stretched surface. The power law model is assumed to have the thermal characteristics of ethylene glycol material. The phenomenon of momentum and energy balance is derived in Cartesian coordinates and developed PD (partial differential)-equations. Swimming pools, solar collectors, food processing, electronic gadgets, cooling systems, magnetic field measurement, computer chips, thermal enhancement, semiconductor characterization, nuclear fusion research and other physical applications are examples of ongoing research. The principle of boundary layer simplified the governing problem. The complex coupled PD (partial differential)-equations have been converted into ordinary differential equations OD (ordinary differential)-equations by using appropriate similarity transformation. The converted boundary value problem is complex and highly nonlinear which does not have the exact solution. The approximate solution is computed numerically via finite element scheme (FES) which is coded in MAPLE 18.0 symbolic package. The convergence of the scheme is established through grid independent survey and the solution is plotted against numerous involved parameters. Thermal performance produced by [Formula: see text]-[Formula: see text]-[Formula: see text]/EG is higher thermal performance produced by [Formula: see text]-[Formula: see text]/EG. Ion slip and Hall forces are responsible for generating Joule heating mechanism that is responsible for reduction of velocity curve and generating shear stresses. Hence, tangential stresses are declined against increasing [Formula: see text] and [Formula: see text].

5.
Sci Rep ; 12(1): 21577, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517500

RESUMO

Inclusion of nanoparticles boosts thermal performance and is essential for thermal transport. The current investigation has been made to conduct research on heat mass transport in synovial material with the mixing of hybrid and tri-hybrid comprising variable viscosity past over a heated surface having constant density and a steady environment. The conservation laws have been considered in the presence of Lorentz force, heat generation/absorption, modified heat and mass fluxes together with chemical reaction. The mathematical model is developed in Cartesian coordinate in the form of coupled partial differential equation (PDEs). The derived PDEs are simplified by a boundary layer approach (BLA) and reduced PDEs have been converted into ordinary differential equation (ODEs) using scaling group Similarity transformation. The converted ODEs are highly nonlinear and have been solved numerically by finite elements scheme (FES). The used scheme is effective for nonlinear problem and can be frequently utilized to tackle nonlinear problems arising in mathematical physics.


Assuntos
Nanoestruturas , Líquido Sinovial , Viscosidade , Análise de Elementos Finitos , Suspensões
6.
Sci Rep ; 12(1): 18970, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36347917

RESUMO

The utilization of Fourier's law of heat conduction provides the parabolic partial differential equation of thermal transport, which provides the information regarding thermal transport for the initial time, but during many practical applications, this theory is not applicable. Therefore, the utilization of modified heat flux model is to be used. This work discusses the utilization of non-Fourier heat flux model to investigate thermal performance of tri-hybrid nanoparticles mixture immersed in Carreau Yasuda material past over a Riga plate by using Hamilton Crosser and Yamada Ota models considering the variable thermos-physical characteristics. The phenomenon presenting the transport of momentum and energy are developed in the form of coupled partial differential equations, which are complex and then transformed into ordinary differential equations by using an appropriate transformation. The transformed equations have been tackled numerically via finite element scheme and the authenticity of obtained solution is shown with the help of comparative analysis of present results with those are available in open literature.


Assuntos
Temperatura Alta , Modelos Teóricos , Análise de Elementos Finitos , Condutividade Térmica
8.
Sci Rep ; 12(1): 13497, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931730

RESUMO

Boosting of thermal transportation is the demand of current era. Several techniques have been used to do so. One of an important way is the mixing of nanoparticles to boost thermal performance. Current investigation has been prepared to study the inclusion of tri hybrid nanoparticles in Prandtl fluid model past over a stretched heated sheet. Modelling of consider problem has been done due to consideration of movement in flow in Cartesian coordinates which results coupled partial differential equation system thermal transport in presented by considering generalized heat flux model and heat generation/absorption. The derived coupled complex partial differential equations (PDEs) system is simplified by engaging boundary layer theory. Such developed model is used in coolants regarding automobiles, dynamics in fuel and production of solar energy, fuel cells, optical chemical sensors, automotive parts, dental products, cancer therapy, electrical insulators and dental products. Handling of complex PDEs for the solution is a challenging task. Due to complexity in computational work these PDEs have been transformed into ordinary differential equations (ODEs) after applying similarity transformation afterwards converted ODEs have been approximated via finite element algorithm coded in MAPLE 18.0 symbolic computational package. Comparative study has been presented for the validity of code and authenticity of obtained result. It is observed that fluid velocity for tri-hybrid nanoparticles is higher than fluidic motion for pure fluid, nanofluid and hybrid nanomaterial.


Assuntos
Nanopartículas , Nanoestruturas , Análise de Elementos Finitos , Modelos Teóricos , Movimento (Física)
9.
Sci Rep ; 12(1): 12206, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842471

RESUMO

Flow in a rotating cone for magnetized Prandtl fluid model is inspected in this investigation. The momentum equation of Prandtl model is derived under the consideration of Hall and ion slip effects and heat transport phenomenon is considered with Joule heating and viscous dissipation effects. The model of Hamilton Crosser and Yamada Ota are considered for the empirical relations of nanofluid mixture. The flow presenting expression of Prandtl fluid model with thermal transport is modeled under boundary layer approximation in the form of partial differential equations (PDEs). The derived PDEs have been converted into set of coupled nonlinear ordinary differential equations (ODEs) by engaging an appropriate scaling group transformation and these converted nonlinear set of ODEs have been tackled numerically via finite element scheme (FES). Impact of different emerging parameters has been displayed graphically and the physics behind the observed phenomena is explained in detail. The convergence of FES is established by carrying the grid independent survey. From the performed investigation, it is recorded that the parameters appear due to Hall and Ion slip currents enhance the fluid velocity but the inverse behavior is recorded for temperature profile.

10.
Sci Rep ; 12(1): 9219, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35654805

RESUMO

Thermal performance can be enhanced due to the mixing of nanoparticles in base fluid. This research discusses the involvement of ternary hybrid nanoparticles in the mixture of pseudo-plastic fluid model past over a two dimensional porous stretching sheet. Modelling of energy equation is carried out in the presence of external heat source or sink and viscous dissipation. The flow presenting equations and derived in Cartesian coordinate system under usual boundary layer theory in the form of complex coupled partial differential equations (PDEs). The derived PDEs have been converted into corresponding ordinary differential equations (ODEs) with the engagement of suitable transformation. The engineers, scientists and mathematicians have great interest in the solution of differential equations because to understand the real physics of the problem. Here, finite element scheme has been used to approximate the solution of the converted problem. The contribution of several emerging parameters on solution have been displayed through graphs and discussed. It is recommended that the finite element method can be engaged to approximate the solution of nonlinear problems arising in modelling the problem in mathematical physics.

11.
Sci Rep ; 12(1): 10306, 2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35718797

RESUMO

The dynamic of fluids and coolants in automobiles are achieved by enhancement in heat energy using ternary hybrid nanostructures. Ternary hybrid nanomaterial is obtained by suspension of three types of nanofluid (aluminum oxide, silicon dioxide and titanium dioxide) in base fluid (EG). Prime investigation is to address comparison study in thermal energy involving various flow models termed as Maxwell fluid and Williamson fluid. This exploration is carried out by partially ionized fluidic particles in the presence of ternary hybrid nanomaterial over cone. Heat transfer is carried out by heat source and thermal radiation. Equations regarding Ordinary differential are achieved from PDEs using variable transformations. The numerical consequences are obtained implementing finite element method. Flow into fluid particles is enhanced versus higher values of Hall and ion slip parameters. Thermal performance as well as flow performance for the case Williamson fluid is better than for case of Maxwell fluid. Production via energy is boosted versus heat source parameter.

12.
Sci Rep ; 12(1): 10219, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715451

RESUMO

The mechanism of thermal transport can be enhanced by mixing the nanoparticles in the base liquid. This research discusses the utilization of nanoparticles (tri-hybrid) mixture into Carreau-Yasuda material. The flow is assumed to be produced due to the stretching of vertical heated surface. The phenomena of thermal transport are modeled by considering Joule heating and heat generation or absorption involvement. Additionally, activation energy is engaged to enhance heat transfer rate. The mathematical model composing transport of momentum, heat and mass species is developed in Cartesian coordinate system under boundary layer investigation in the form of coupled nonlinear partial differential equations. The complex partial differential equations are converted into coupled nonlinear ordinary differential equations by using the appropriate similarity transformation. The conversion of PDEs into ODEs make the problem easy to handle and it overcome the difficulties to solve the PDEs. The transformed ordinary differential equations are solved with the help of help of finite element scheme. The obtained solution is plotted against numerous involved parameters and comparative study is established for the reliability of method and accuracy of obtained results. An enhancement in fluid temperature is recorded against magnetic parameter and Eckert number. Also, decline in velocity is recorded for Weissenberg number and concentration is controlled against higher values of Schmidt number. Furthermore, it is recommended that the finite element scheme can be implemented to handle complex coupled nonlinear differential equation arising in modeling of several phenomena occurs in mathematical physics.


Assuntos
Temperatura Alta , Hidrodinâmica , Difusão , Transferência de Energia , Reprodutibilidade dos Testes
13.
Micromachines (Basel) ; 13(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35208325

RESUMO

The rheology of different materials at the micro and macro levels is an area of great interest to many researchers, due to its important physical significance. Past experimental studies have proved the efficiency of the utilization of nanoparticles in different mechanisms for the purpose of boosting the heat transportation rate. The purpose of this study is to investigate heat and mass transport in a pseudo-plastic model past over a stretched porous surface in the presence of the Soret and Dufour effects. The involvement of tri-hybrid nanoparticles was incorporated into the pseudo-plastic model to enhance the heat transfer rate, and the transport problem of thermal energy and solute mechanisms was modelled considering the heat generation/absorption and the chemical reaction. Furthermore, traditional Fourier and Fick's laws were engaged in the thermal and solute transportation. The physical model was developed upon Cartesian coordinates, and boundary layer theory was utilized in the simplification of the modelled problem, which appears in the form of coupled partial differential equations systems (PDEs). The modelled PDEs were transformed into corresponding ordinary differential equations systems (ODEs) by engaging the appropriate similarity transformation, and the converted ODEs were solved numerically via a Finite Element Procedure (FEP). The obtained solution was plotted against numerous emerging parameters. In addition, a grid independent survey is presented. We recorded that the temperature of the tri-hybrid nanoparticles was significantly higher than the fluid temperature. Augmenting the values of the Dufour number had a similar comportment on the fluid temperature and concentration. The fluid temperature increased against a higher estimation of the heat generation parameter and the Eckert numbers. The impacts of the buoyancy force parameter and the porosity parameter were quite opposite on the fluid velocity.

14.
Sci Rep ; 12(1): 2335, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35149694

RESUMO

The study of thermo-physical characteristics is essential to observe the impact of several influential parameters on temperature and velocity fields. The transportation of heat in fluid flows and thermal instability/stability is a charming area of research due to their wider applications and physical significance because of their utilization in different engineering systems. This report is prepared to study thermal transportation in Maxwell hybrid nanofluid past over an infinite stretchable vertical porous sheet. An inclusion of hybrid nanofluid is performed to monitor the aspects of thermal transportation. Keeping in mind the advantages of thermal failure, non-Fourier theory for heat flux model is utilized. Aspects of external heat source are also considered. The mathematical formulation for the considered model with certain important physical aspects results in the form of coupled nonlinear PDEs system. The obtained system is reduced by engaging boundary layer approximation. Afterwards, transformations have been utilized to convert the modeled PDEs system into ODEs system. The converted nonlinear ODEs system is then handled via finite element method coded in symbolic computational package MAPLE 18.0. Grid independent survey is presented for the validation of used approach and the comparative analysis has been done to confirm the reliability of obtained solution. The obtained solution is discussed and physical aspects have been explored and recorded against numerous involved influential variables. Motion into hybrid nanoparticles and nanoparticles becomes slow down versus higher values of Forchheimer and Darcy's porous numbers. Thermal growth is enhanced for the case of hybrid nano-structures rather than for case of nanofluid. Thickness regarding momentum layer is dominated for hybrid nanoparticles rather than case of nanoparticles.

15.
Micromachines (Basel) ; 12(11)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34832714

RESUMO

Engineers, scientists and mathematicians are greatly concerned about the thermal stability/instability of any physical system. Current contemplation discusses the role of the Soret and Dufour effects in hydro-magnetized Carreau-Yasuda liquid passed over a permeable stretched surface. Several important effects were considered while modelling the thermal transport, including Joule heating, viscous dissipation, and heat generation/absorption. Mass transportation is presented in the presence of a chemical reaction. Different nanoparticle types were mixed in the Carreau-Yasuda liquid in order to study thermal performance. Initially, governing laws were modelled in the form of PDEs. Suitable transformation was engaged for conversion into ODEs and then the resulting ODEs were handled via FEM (Finite Element Method). Grid independent analysis was performed to determine the effectiveness of the chosen methodology. Several important physical effects were explored by augmenting the values of the influential parameters. Heat and mass transfer rates were computed against different parameters and discussed in detail.

16.
Sci Rep ; 11(1): 19604, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599255

RESUMO

Involvement of hybrid nanoparticles a vital role to improve the efficiency of thermal systems. This report covers the utilization of different nanoparticles mixed in Carreau Yasuda material for the improvement of thermal performance. The configuration of flow situation is considered over a rotating porous cone by considering the Hall and Ion slip forces. Transport of momentum is considered to be in a rotating cone under generalized ohm's law and heat transfer is presented by considering viscous dissipation, Joule heating and heat generation. Rheology of considered model is derived by engaging the theory proposed by Prandtl. Modeled complex PDEs are reduced into ODEs under similarity transformation. To study the physics behind this phenomenon, solution is essential. Here, FEM (Finite Element Method) is adopted to compute the solution. Furthermore, the grid independent study is reported with several graphs and tables which are prepared to note the influence of involved parameters on thermal and velocity fields. It is worth mentioning that heat transport is controlled via higher radiation parameter and it upsurges for Eckert number. Moreover, Hall and ion slip parameters are considered significant parameters to produce the enhancement in motion of fluid particles but speed of nano and hybrid nanoparticles becomes slow down versus large values of Forchheimer and Weissenberg numbers. Additionally, an enhancement in production of heat energy is addressed via large values of heat generation number and Eckert number while reduction in heat energy is occurred due to positive values of thermal radiation and Hall and ion slip parameters.

17.
Sci Rep ; 11(1): 17837, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34497311

RESUMO

Stretched flows have numerous applications in different industrial, biomedical and engineering processes. Current research is conducted to examine the flow phenomenon of Prandtl fluid model over a moveable surface. The phenomenon of mass and thermal transportation is based on generalized theory of Cattaneo-Christov which considers the involvement of relaxation times. In addition to these, variable characteristics of thermal conductivity and diffusion coefficient are considered as a function of temperature. The physical problem in Cartesian coordinate system is modeled via boundary layer theory which yields a coupled system of partial differential equations. Group scaling transportation is applied to model these PDEs system. The converted equations have been approximated via optimal homotopic scheme. The efficiency and validity of used approach has been shown by computing the error analysis and establishing a comparative study. It is noted that the enhancement in magnetic parameter plays a controlling role for velocity field and it augment the concentration and temperature fields. Furthermore, increase in thermal relaxation parameter and Prandtl number maintains the fluid temperature.

18.
PLoS One ; 16(8): e0256302, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34432830

RESUMO

This report is prepared to examine the heat transport in stagnation point mixed convective hyperbolic tangent material flow past over a linear heated stretching sheet in the presence of magnetic dipole. Phenomenon of thermal transmission plays a vital role in several industrial manufacturing processes. Heat generation is along with thermal relaxation due to Cattaneo-Christov flux is engaged while modeling the energy equation. In order to improve the thermal performance, inclusion of hybrid nanoparticles is mixed in hyperbolic tangent liquid. The conservation laws are modeled in Cartesian coordinate system and simplified via boundary layer approximation. The modeled partial differential equations (PDEs) system are converted into ordinary differential equations (ODEs) system by engaging the scaling group transformation. The converted system of modeled equations has been tackled via finite element procedure (FEP). The efficiency of used scheme has been presented by establishing the grid independent survey. Moreover, accurateness of results is shown with the help of comparative study. It is worth mentioning that the inclusion of hybrid nanoparticles has significant higher impact on heat conduction as compared with nanoparticle. Moreover, hybrid nanoparticles are more efficient to conduct maximum production of heat energy as compared with the production of heat energy of nanoparticles. Hence, hybrid nanoparticles (MoS2/Ag) are observed more significant to conduct more heat energy rather than nanoparticle (Ag).


Assuntos
Modelos Teóricos , Nanopartículas/química , Fenômenos Físicos , Algoritmos , Elasticidade , Análise de Elementos Finitos , Temperatura Alta , Condutividade Térmica , Meios de Transporte , Viscosidade
19.
Micromachines (Basel) ; 12(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34442573

RESUMO

This report examines the heat and mass transfer in three-dimensional second grade non-Newtonian fluid in the presence of a variable magnetic field. Heat transfer is presented with the involvement of thermal relaxation time and variable thermal conductivity. The generalized theory for mass flux with variable mass diffusion coefficient is considered in the transport of species. The conservation laws are modeled in simplified form via boundary layer theory which results as a system of coupled non-linear partial differential equations. Group similarity analysis is engaged for the conversion of derived conservation laws in the form of highly non-linear ordinary differential equations. The solution is obtained vial optimal homotopy procedure (OHP). The convergence of the scheme is shown through error analysis. The obtained solution is displayed through graphs and tables for different influential parameters.

20.
J Family Med Prim Care ; 10(11): 4137-4142, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35136779

RESUMO

BACKGROUND: A multipurpose health worker (MPHW) is the pivotal functionary and the first point of contact in health care sector. This study explores the work-related activity of MPHWs in the different domains and also assesses their time utilization pattern. METHODS: A time and motion study was conducted among 12 multipurpose health care workers (MPHWs) from 10 different Subcenters of block Hazratbal. Participants self-reported their daily activities on a time measurement sheet for 6 days. Data were entered in Microsoft Excel and analyzed using SPSS v25.0. Calculations are based on a total of 544.5 person-hours of observation by ANMs. RESULTS: Time utilization pattern revealed that ANMs spent one-fourth of their time on maintaining registers. Observations on self-reporting were comparable with that of observations made by external observers. CONCLUSIONS: This study reflects the workload in different domains of MPHWs' activities and nature of their work, relevance of their job responsibilities in the context to Indian public health standards for their job.

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