On the assessment of stationary points and uniform film thickness for the thin film flow of Sisko fluid model

Thin films and coatings which have a high demand in a variety of industries—such as manufacturing, optics, and photonics—need regular improvement to sustain industrial productivity. Thus, the present work examined the problem of the Carreau thin film flow and heat transfer with the influence of thermocapillarity over an unsteady stretching sheet, numerically. The sheet is permeable, and there is an injection effect at the surface of the stretching sheet. The similarity transformation reduced the partial differential equations into a system of ordinary differential equations which is then solved numerically by the MATLAB boundary value problem solver bvp4c. The more substantial effect of injection was found to be the reduction of the film thickness at the free surface and development of a better rate of convective heat transfer. However, the increment in the thermocapillarity number thickens the film, reduces the drag force, and weakens the rate of heat transfer past the stretching sheet. The triple solutions are identified when the governing parameters vary, but two of the solutions gave negative film thickness. Detecting solutions with the most negative film thickness is essential because it implies the interruption in the laminar flow over the stretching sheet, which then affects the thin film growing process.

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Heat Transfer Analysis of Cu and Al 2 0 3 Dispersed in Ethylene Glycol as a Base Fluid over a Stretchable Permeable Sheet of MHD Thin-film Flow

10.21203/rs.3.rs-991859/v1 ◽

2021 ◽

Author(s):

Zeeshan Khan ◽

Ilyas Khan

Keyword(s):

Thin Film ◽

Heat Transfer ◽

Differential Equations ◽

Ethylene Glycol ◽

Film Thickness ◽

Film Flow ◽

Heat Transfer Analysis ◽

Hybrid Nanofluid ◽

Thin Film Flow ◽

Thin Film Thickness

Abstract The process of thin films is commonly utilized to improve the surface characteristics of materials. A thin film helps to improve the absorption, depreciation, flexibility, lighting, transport, and electromagnetic efficiency of a bulk material medium. Thin film treatment can be especially helpful in nanotechnology. As a result, the current study investigates the computational process of heat relocation analysis in a thin-film MHD flow embedded in hybrid nanoparticles, which combines the spherical copper and alumina dispersed in ethylene glycol as the conventional heat transfer Newtonian fluid model over a stretching sheet. Important elements such as thermophoresis and Brownian movement are used to explain the characteristics of heat and mass transfer analysis. Nonlinear higher differential equations (ODEs) were attained by transforming partial differential equations (PDEs) into governing equations when implementing the similarity transformation technique. The resulting nonlinear ODEs have been utilized by using the homotopy analysis method (MHD). The natures of the thin-film flow and heat transfer through the various values of the pertinent parameters: unsteadiness, nanoparticle volume fraction, thin-film thickness, magnetic interaction and intensity suction/injection are deliberated. The approximate consequences for flow rate and temperature distributions and physical quantities in terms of local skin friction and Nusselt number were obtained and analysed via graphs and tables. As a consequence, the suction has a more prodigious effect on the hybrid nanofluid than on the injection fluid for all the investigated parameters. It is worth acknowledging that the existence of the nanoparticles and MHD in the viscous hybrid nanofluid tends to enhance the temperature profile but decay the particle movement in the thin-film flow. It is perceived that the velocity and temperature fields decline with increasing unsteadiness, thin-film thickness and suction/injection parameters.

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MAGNETOHYDRODYNAMIC THIN FILM FLOW OF A SISKO FLUID IN A POROUS SPACE

Journal of Porous Media ◽

10.1615/jpormedia.v13.i6.60 ◽

2010 ◽

Vol 13 (6) ◽

pp. 565-571

Author(s):

Tasawar Hayat ◽

M. Usman Ashraf ◽

S. Asghar

Keyword(s):

Thin Film ◽

Film Flow ◽

Porous Space ◽

Thin Film Flow ◽

Sisko Fluid

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Nanofluid thin film flow of Sisko fluid and variable heat transfer over an unsteady stretching surface with external magnetic field

Journal of Algorithms & Computational Technology ◽

10.1177/1748301819832456 ◽

2019 ◽

Vol 13 ◽

pp. 174830181983245 ◽

Cited By ~ 5

Author(s):

Muhammad Jawad ◽

Zahir Shah ◽

Saeed Islam ◽

Waris Khan ◽

Aurang Zeb Khan

Keyword(s):

Magnetic Field ◽

Thin Film ◽

Brownian Motion ◽

Liquid Film ◽

Film Flow ◽

Thin Film Flow ◽

Sisko Fluid ◽

Variable Heat ◽

Liquid Film Flow ◽

Optimal Approach

This research paper investigates two dimensional liquid film flow of Sisko nanofluid with variable heat transmission over an unsteady stretching sheet in the existence of uniform magnetic field. The basic governing time-dependent equations of the nanofluid flow phenomena with Sisko fluid are modeled and reduced to a system of differential equations with use of similarity transformation. The significant influence of Brownian motion and thermophoresis has been taken in the nanofluids model. An optimal approach is used to obtain the solution of the modeled problems. The convergence of the Homotopy Analysis Method (HAM) method has been shown numerically. The variation of the skin friction, Nusselt number and Sherwood number, their influence on liquid film flow with heat and mass transfer have been examined. The influence of the unsteadiness parameter [Formula: see text] over thin film is explored analytically for different values. Moreover for comprehension, the physical presentation of the embedded parameters, like [Formula: see text], magnetic parameter [Formula: see text], stretching parameter [Formula: see text] and Sisko fluid parameters [Formula: see text], Prandtl number Pr, thermophoretic parameter [Formula: see text], Brownian motion parameter [Formula: see text], Schmidt number [Formula: see text] have been represented by graph and discussed.

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Analysis of Uniform Film Thickness and Stationarypoints for the Thin Film Flow of Carreau Fluid Model in the Presence of Surface Tension Gradient

10.21203/rs.3.rs-1221961/v1 ◽

2022 ◽

Author(s):

Hameed Ashraf ◽

Abida Parveen ◽

Hamood Ur Rehman ◽

Muhammad Imran Asjad ◽

Bander N. Almutairi ◽

...

Keyword(s):

Surface Tension ◽

Film Thickness ◽

Film Flow ◽

Fluid Model ◽

Shear Thickening ◽

Fluid Film ◽

Stationary Points ◽

Surface Tension Gradient ◽

Carreau Fluid ◽

Moving Cylinder

Abstract This article addresses the analysis of the uniform film thickness and stationary points forthe Carreau thin fluid film flow. The flow of fluid on a vertically upward moving cylinder takesplace in the presence of a surface tension gradient. The resulting non-linear and inhomogeneousordinary differential equation is solved for the series form solution using Adomian decompositionmethods (ADM). Stokes number St, inverse capillary number C, Weissenberg number W e andfluid behavior index n emerged as flow control parameters. The analysis showed that thepositions of stationary points transferred towards the surface of the cylinder by the increase ofSt and C while towards the fluid-air interface by the increase of n. W e delineated vice versaeffects on positions of stationary points for the shear thickening fluid film and shear thinningfluid film. The width of uniform film thickness reduces by an increment in the St and Cwhereas it increases by an increment in the n. The width of shear thickening uniform filmthickness increases whilst shear thinning uniform film thickness decreases as the W e increases. A comparison between the linearly viscous fluid and Carreau fluid is also made.

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MHD dissipative Casson nanofluid liquid film flow due to an unsteady stretching sheet with radiation influence and slip velocity phenomenon

Nanotechnology Reviews ◽

10.1515/ntrev-2022-0031 ◽

2022 ◽

Vol 11 (1) ◽

pp. 463-472

Author(s):

Elham Alali ◽

Ahmed M. Megahed

Keyword(s):

Thin Film ◽

Mass Transfer ◽

Film Thickness ◽

Liquid Film ◽

Slip Velocity ◽

Film Flow ◽

Physical Parameters ◽

Thin Film Flow ◽

Thin Film Layer ◽

Film Layer

Abstract The problem of non-Newtonian Casson thin film flow of an electrically conducting fluid on a horizontal elastic sheet was studied using suitable dimensionless transformations on equations representing the problem. The thin film flow and heat mechanism coupled with mass transfer characteristics are basically governed by the slip velocity, magnetic field, and the dissipation phenomenon. The present numerical analysis by the shooting method was carried out to study the detailed, fully developed heat and mass transfer techniques in the laminar thin film layer by solving the competent controlling equations with eight dominant parameters for the thin liquid film. Additionally, the predicted drag force via skin-friction coefficient and Nusselt and Sherwood numbers were correlated. In view of the present study, a smaller magnetic parameter or a smaller slip velocity parameter exerts very good influence on the development of the liquid film thickness for the non-Newtonian Casson model. Furthermore, a boost in the parameter of unsteadiness causes an increase in both velocity distribution and concentration distribution in thin film layer while an increase in the same parameter causes a reduction in the film thickness. Likewise, the present results are observed to be in an excellent agreement with those offered previously by other authors. Finally, some of the physical parameters in this study, which can serve as improvement factors for heat mass transfer and thermophysical characteristics, make nanofluids premium candidates for important future engineering applications.

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Thin-Film Flow Over a Rotating Plate: An Assessment of the Suitability of VOF and Eulerian Thin-Film Methods for the Numerical Simulation of Isothermal Thin-Film Flows

Volume 5C: Heat Transfer ◽

10.1115/gt2015-43506 ◽

2015 ◽

Cited By ~ 1

Author(s):

B. Kakimpa ◽

H. P. Morvan ◽

S. Hibberd

Keyword(s):

Thin Film ◽

Film Thickness ◽

Film Flow ◽

Computational Cost ◽

Inlet Temperature ◽

Thin Film Flow ◽

Vof Model ◽

Fluid Properties ◽

Thickness Variations ◽

Rotating Plate

An isothermal thin-film flow over a rotating plate has been simulated using the depth-averaged Eulerian Thin-Film modelling (ETFM) approach. The model setup is based on published experimental and numerical Volume of Fluid (VOF) CFD studies of the same problem to allow for model validation. A range of controlled film inlet heights and mass flow rates are explored together with varied plate rotational speeds ranging from a stationary plate (50rpm) to 200 rpm. While the VOF model has previously been shown to accurately reproduce film thickness, the Eulerian thin-film model is shown to provide predictions of comparable accuracy at a much lower computational cost. The model is also shown to be able to reproduce the film solution’s sensitivity to variations in fluid properties due to changes in inlet temperature. A full 3D domain has been used in this study and the ETFM model is also shown to be able to reproduce azimuthal film thickness variations and surface features similar to those previously observed in experiments.

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Asymptotic Modeling of the Thin Film Flow with a Pressure-Dependent Viscosity

Journal of Applied Mathematics ◽

10.1155/2014/217174 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Eduard Marušić-Paloka ◽

Igor Pažanin

Keyword(s):

Thin Film ◽

Film Thickness ◽

Asymptotic Analysis ◽

Film Flow ◽

Thin Film Flow ◽

Asymptotic Modeling ◽

Governing System ◽

Expansion Technique ◽

Pressure Dependent Viscosity ◽

Dependent Viscosity

We study the lubrication process with incompressible fluid taking into account the dependence of the viscosity on the pressure. Assuming that the viscosity-pressure relation is given by the well-known Barus law, we derive an effective model using asymptotic analysis with respect to the film thickness. The key idea is to conveniently transform the governing system and then apply two-scale expansion technique.

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Thermal energy transport in thin film flow of nanofluid over a decelerating rotating disk

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/09544089211050717 ◽

2021 ◽

pp. 095440892110507

Author(s):

Latif Ahmad ◽

Jawad Ahmed ◽

Awais Ahmed

Keyword(s):

Thin Film ◽

Heat Transfer ◽

Film Thickness ◽

Energy Transport ◽

Film Flow ◽

Rotating Disk ◽

Brownian Diffusion ◽

Thin Film Flow ◽

Thickness Skin ◽

Buongiorno Model

The thin film flow in nanotechnology is one of the most modern progresses in the study of thin films. This includes coating with nanocomposite materials, thus providing the materials improved mechanical properties due to a so-called size effect. The ultimate functional properties that can be gained are of high adherence, wear resistance, thermal conductivity, oxidation resistance, higher toughness and hardness. This article studies the transient motion of nanofluid thin film over a disk rotating with angular velocity inversely proportional to the time. The importance of Lorentz force arises due to the axial projection of magnetic flux is studied on thin film flow and heat transfer. Two active mechanisms of nanoparticles, namely thermophoresis and Brownian diffusion, are discussed using Buongiorno model. By adopting a similarity method, the velocity distribution thermal and concentration fields above the rotating disk are simulated numerically and assessed graphically. Numerical illustrations for nanofluid film thickness, skin friction and heat and mass transfer rates are depicted against the impacts of several influential parameters. Results highlight that film thickness reduces with unsteadiness and rotation parameters. The results also spectacle that the involvement of a magnetic beam reduces the velocity of nanofluid film. Further, it is observed that thermophoresis and Brownian motion effects make a better influence in enhancing the heat transfer rate.

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Nanofluids Thin Film Flow of Reiner-Philippoff Fluid over an Unstable Stretching Surface with Brownian Motion and Thermophoresis Effects

Coatings ◽

10.3390/coatings9010021 ◽

2018 ◽

Vol 9 (1) ◽

pp. 21 ◽

Cited By ~ 26

Author(s):

Asad Ullah ◽

Ebraheem Alzahrani ◽

Zahir Shah ◽

Muhammad Ayaz ◽

Saeed Islam

Keyword(s):

Thin Film ◽

Brownian Motion ◽

Film Flow ◽

Fluid Model ◽

Time Dependent ◽

Thin Film Flow ◽

Stretching Surface ◽

Fluid Parameter ◽

Homotopy Analysis ◽

Dependent Parameter

The current investigation is carried out on the thin film flow of Reiner-Philippoff fluid of boundary-layer type. We have analyzed the flow of thin films of Reiner-Philippoff fluid in the changeable heat transmission and radiation over a time-dependent stretching sheet in 2D. The time-dependent governing equations of Reiner-Philippoff fluid model are simplified with the help of transformation of similarity variables. To investigate the behavior of the Reiner-Philippoff fluid with variable stretching surface for different physical effects, we considered thermophoresis and Brownian motion parameters in the flow. The Homotopy Analysis Method is implemented in the reduced model to achieve a solution of the original problem. A numerical convergence of the implemented method is also analyzed. The behavior of temperature, velocity, and concentration profiles have been investigated with the variation of skin friction, Nusselt number, and Sherwood number. A comparative graphical survey is presented for the velocity gradient, under different parameters. An analytical analysis is presented for the time-dependent parameter over thin film flow. The results we obtained are better than the previously available results. For the survey, the physical representation of the embedded parameters, like, β depends on the stretching parameter ζ , and the Reiner-Philippoff fluid parameter ϵ are discussed in detail and plotted graphically. Prandtl number P r , Brownian motion parameter N b , thermophoretic number N t , and Schmidt number S c are presented by graphs and discussed in detail.

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