Local Skin Friction Research Articles

Impact of double diffusivity on the hyperbolic tangent model conveying nano fluid flow over the wedge

The significant thing in our analysis is to inspect the double-diffusivity convection for the hyperbolic tangent nanofluid model, under the spotlight effects of activation energy and viscosity over the wedge-shaped geometry. Activation energy enunciates chemical reaction and also Buongiorno model is applied to highlight the important features of the thermophoresis and Brownian diffusion coefficient. The convection of double diffusivity is illustrated through Soret and Dufour parameter. The mathematical modeling of demarcated flow produces a collection of non-linear partial differential equations, which are consequently transmuted into ordinary differential equations using suitable transformation. The graphical results for these ordinary differential equations are created using the Bvp4c approach. The effect of pertinent parameters on fluid flow, thermal variation, concentration and double diffusivity profiles are examined. The velocity field generally behaves as the decreasing function of thermal and nanofluid Grashof number but surges along the Solutal Grashof number. The Brownian diffusion coefficient surges the temperature profile and minors the concentration and double-diffusivity. Soret diffusivity surges the concentration distribution when fluid crosses the edge of the wedge. The nanofluid Lewis number particularly slows down the double-diffusivity profile. The graphical sketches of local skin friction, Nusselt number, Sherwood number, isothermal contour and streamlines flow elaborated our analyses more precisely.

Unsteady Fluid Flow in a Darcy–Brinkman Porous Medium with Slip Effect and Porous Dissipation

In this paper, the significance of slip situations in the appearance of a porous medium and frictional heating on unsteady fluid flow through a porous medium has been explored. The numerical solutions of the differential equation representing fluid flow through a porous material, including slip effects, are presented. We have obtained a nonlinear ordinary differential equation using a similarity transformation. Under velocity and thermal slip conditions, the Maple packages were used to numerically solve the resulting set of nonlinear problems. Both the velocity and temperature increase when the Brinkman viscosity ratio parameter [Formula: see text] increases. The effects of the nondimensional parameters on the governing flow velocity and temperature are examined with graphical profiles. The implications of relevant parameters on dimensionless temperature, velocity, local Nusselt number and skin friction coefficient are shown and explained. For various flow quantities of interest, the fluctuation of parameters is investigated, and the results are given in the system of graphs and tables.

Viscous Dissipation Effect on Magnetohydrodynamics Fluid Flow Over an Exponential Surface with the Influence of Thermal Radiation and Thermal Diffusion

This present investigation studies the effect of viscous dissipation in magnetohydrodynamics fluid flow over an exponential surface subject to the influence of thermal radiation and thermal diffusion. The coupled nonlinear guiding equations responsible for the flow, heat and mass transports presented as partial differential equations are revamped to the associated ordinary differential equation by application of the associated similarity variables and solved by Galerkin Weighted residual method (GWRM). The results of various parameters encountered are analyzed with graphs while the Sherwood number, Nussetl number, and local skin friction are computed and discussed. The study demonstrates, among other things, that the fluid has a strong thermal conductivity at low Prandtl numbers and that heat diffuses from the surface more quickly at low Prandtl numbers in comparison with the higher values.

Radiation Effects on Boundary Layer Flow and Heat Transfer of the Power Law Fluid Over a Stretching Cylinder with Convective Boundary Conditions

In this work, a power law fluid model is used to examine the boundary layer flow and heat transfer characteristics over an unsteady horizontal stretching cylinder under the influence of convective boundary conditions. It is presumed that partial slip conditions exist and that the thermal conductivity of the nanofluid is a function of temperature at the boundary. Through similarity transformation, the coupled partial differential equations are converted into ordinary differential equations (ODEs), which are then resolved in MATLAB with BVP4C. By contrasting the computed findings with the published results, the validity of the results is proven. The effects of different parameters on the temperature and velocity profiles are carefully looked at and analysed. As the Eckert number increases, the thermal boundary layer thickens. All of the physical factors that affect the local Nusselt number and skin friction coefficient have been studied carefully and are shown in the tables.

VIV and forced convection response of a freely oscillating cylinder to a single impulse perturbation of varying intensity

A numerical investigation into the effects of single gust impulse on the flow physics, dynamic response, and heat transfer from an undamped two degrees of freedom circular cylinder is presented for a constant property, incompressible Newtonian fluid at a low Reynolds number range, 70≤Re≤150 and Prandtl number Pr=7. Structural natural frequency (FN) is set equal to the vortex shedding frequency of a static circular cylinder (fv) at Re=100 and is kept constant in both the degrees of freedom such that FN=FNx=FNy. Mass ratio is m*=10, while structural damping is set to zero (ζ=0). Intensities of gust impulse are varied as a function of inlet velocity while keeping the frequency of gust impulse fixed, in order to isolate the effects of intensity of gust only. Results pertaining to transient effects of gust impulse on the fluidic forces, dynamic response, and conjugate heat transfer are presented. Time histories of lift coefficient show a pattern of quicker recovery from gust in the lock-in regime. Shifting of primary and secondary frequencies due to gust impulse is observed. A very organized and regular pattern of cylinder dislodgement and recovery is observed in the lock-in regimes as opposed to chaotic behaviour out of the lock-in regime. The vortex street is seen to eventually stabilize and restore itself to its original pre-gust oscillatory behaviour. Vorticity contours depict an early vortex detachment due to the shear layers’ stretching followed by a pair of counter rotating vortices shed simultaneously. Consequent evolution of heat transfer behaviour from the cylinder surface is also recorded in the temperature contours. Furthermore, local Nusselt number at the front end of the cylinder depicts remarkable sensitivity to the gust intensity. Increase in gust intensity also causes higher peak values of local skin friction coefficient.

Heat transfer characteristics of magnetized hybrid ferrofluid flow over a permeable moving surface with viscous dissipation effect

Hybrid ferrofluid is a unique heat transfer fluid because it can be magnetically controlled and ideal in various applications. Further exploration to unleash its potential through studying heat transfer and boundary layer flow is crucial, especially in solving the thermal efficiency problem. Hence, this research focuses on the numerical examination of flow behaviour and heat transfer attributes of magnetized hybrid ferrofluid Fe3O4-CoFe2O4/water across a permeable moving surface considering the mutual effects of magnetohydrodynamic (MHD), viscous dissipation, and suction/injection. The problem was represented by the Tiwari and Das model with duo magnetic nanoparticle hybridization; magnetite Fe3O4 and cobalt ferrite CoFe2O4 immersed in water. The governing equations were transformed into ordinary differential equations using appropriate similarity variables and solved with bvp4c MATLAB. A dual solution is obtained, and via stability analysis, the first solution is stable and physically reliable. The significant influence of governing effects on the temperature and velocity profiles, the local skin friction coefficient and the local Nusselt number are analyzed and visually shown. The surge-up value of suction and CoFe2O4 ferroparticle volume concentration enhances the local skin friction coefficient and heat transfer rate. Additionally, the magnetic parameter and Eckert number reduced the heat transfer. Using a 1% volume fraction of Fe3O4 and CoFe2O4; the hybrid ferrofluid's convective heat transfer rate was shown to be superior to mono-ferrofluid and water by enhancing 2.75% and 6.91%, respectively. This present study also suggests implying a greater volume concentration of CoFe2O4 and lessening the magnetic intensity to maintain the laminar flow phase.

Numerical Investigation by Cut-Cell Approach for Turbulent Flow through an Expanded Wall Channel

The expanded wall channel backward-facing step (BFS) and axisymmetric diffuser plays an important role in the society of fluid dynamics. Using a cut-cell technique is an established new method to treat the inclined wall of an axisymmetric diffuser. Cut-cell handle to reach the shape of the inclined wall, an axisymmetric diffuser and complex geometry. It helps treat the boundary condition at the wall in an accurate physical way. The turbulent flow through the geometries is solved by using Reynolds averaged Navier-Stokes equations (RANS) with the standard k-ε model. A self-built FOTRAN code based on the finite volume method with the Semi-Implicit Method for Pressure Linked Equations (SIMPLE) algorithm for pressure velocity coupling is established and examined with published experimental data for two different geometries backward-facing step (BFS) and axisymmetric diffuser. The results of the new technique reflect good agreement between the numerical results and the experimental data. A parametric study of the impact of area ratios (2, 2.5, 3, 3.5) in a backward-facing step on pressure, velocity, and turbulent kinetic energy. The angles (7°, 10°, 14°) and area ratios (2, 2.5, 3, 3.5) effect of an axisymmetric diffuser on the streamlines, local skin friction, pressure, velocity, turbulent kinetic energy, and separation zone.

Optimization of response function on hydromagnetic buoyancy-driven rotating flow considering particle diameter and interfacial layer effects: Homotopy and sensitivity analysis

Alumina is one of the modern era and most utilized ceramic materials. One example of an electrical insulating substance is alumina. It has an enhanced temperature, chemical stability and higher thermal conductivity. It is mostly used in medical, industry, household items, military purposes, production of batteries and electrical parts. Therefore, the authors have formulated a mathematical model of the three-dimensional magnetohydrodynamic mixed convective flow of a nanofluid containing Alumina nanoparticles past a stretching surface. Preliminary assumptions bound the nanofluid flow to be rotational, electrically conducting, dissipative, buoyancy driven, thermally heated and convective. An important investigation based on the effects of nanoparticle diameter and nanolayer of the nanofluid makes the novelty of this investigation. The modeled problem is solved with a homotopic approach, which is suitable for the solution of the highly nonlinear differential equations and has quick convergence. The outcomes of the present analysis are shown with the help of Tables and Figures. The outcomes showed that the higher resistive force at the sheet surface caused by the higher solid volume fraction (varies from 1% to 4%), diminishes the primary velocity, while escalates the secondary velocity. Additionally, the greater solid volume fraction (which ranges from 1% to 4%) raises the thermal conductivity of the nanofluid flow, resulting in an increasing conduct in the thermal function. The enhancing nanolayer to base fluid conductivity ratio (which ranges from 1.1 to 65.25), results in an increase in both velocities and thermal functions, gives the nanofluid flow a higher thermal conductivity. Additionally, the local Nusselt number and skin friction increase as a result of the higher thermal conductivity. The primary velocity and temperature are reduced due to the decrease in thermal and momentum boundary layer thicknesses brought on by the rising nanoparticle diameter (which ranges from 1 nm to 50 nm). The rate of heat transfer is significantly achieved at the higher levels of the volume fraction and radiation factor while heat source is at lower level. The friction rate at the surface is dominant at higher level values of magnetic and volume fraction factor and medium level of rotation factor. The transport of heat has highest sentivity at the middle level of thermla radaition and volume fraction of the nanoparticle and low level of heat source, while the highest sensitivity of friction factor is observed at the middle level of thermal rotation and high level nanoparticle volume fraction and magnetic factor.

How do the Intravenously Injection of Nanoparticle and Oxytatic Bacteria Affect Through Circular Cylinder Cell for Non-Newtonian Micropolar Fluid: Mathematical Approach

In this paper, we have researched the conduct of non-Newtonian micropolar nanofluid flow through horizontal circular under the impacts of nanoparticles, oxytatic bacterial and Hall current effects. The utilizations of the current investigation are exceptionally powerful in biomedical therapies, for example, obliteration of malignant growth over biological cells by utilizing drug conveyance of nanoparticles and oxytatic microscopic organisms. If there should arise an occurrence of biological nanofluid it’s accepted to concern variable physical parameters which rely on the nanofluid temperature. Implicit Chebyshev pseudospectral (ICPS) technique by helping MATHEMATICA software has been applied to governing nonlinear system of dimensionless partial differential equations (PDEs). The nanofluid velocity, microrotation angular velocity, temperature, motile bacterial density distributions, oxygen concentration, local skin friction coefficient, Nusselt number, and wall motile density gradient distributions are delineated graphically for various variable physical parameters, likewise comparison between certain results in literature and our current output is introduced and great arrangement is found.

Rayleigh-Benard convection of water conveying copper nanoparticles of larger radius and inter-particle spacing at increasing ratio of momentum to thermal diffusivities

As in the case of enhancing the performance of high-temperature superconductors, the dynamics of colloidal mixes of water and copper-based nanoparticles exposed to an inclined magnetic field owing to free convection is a recognized issue. However, nothing is known about the dynamics mentioned above when the radius and inter-particle spacing of copper nanoparticles grow in the presence of Joule dissipation, mass flux owing to a temperature gradient, internal heating, and heat flux due to concentration gradient. When the ratio of momentum to thermal diffusivities is incorporated into the momentum equation using appropriate models, the governing equation (i.e. Partial Differential Equations) that models the transport mentioned above was scaled, solved numerically, and simulated with a focus on the nanoparticle radius and the spacing between copper nanoparticles. The resultant non-linear coupled Ordinary Differential Equation was solved using the MATLAB integrated (i.e. bvp4c software package) and the shooting approach (i.e. fourth-order Runge–Kutta integration strategy shrk4). Just because of the resulting improvement in the temperature distribution, increasing the ratio of momentum to thermal diffusivities leads to a more pronounced local skin friction within the layers adjacent to the wall and heat transfer. Because buoyancy forces are exclusively associated with the growth of concentration difference, they cause the distance covered by the transport phenomenon in terms of the spatial domain to decrease. Higher ratios of momentum to thermal diffusivities cause the full-fledged sheer stress profile, which is proportional to friction across fluid layers, to rise.

Boundary Layer Investigations for Primarily Axial Flow Over a Stationary and Transversely Oscillating Cylinder

AbstractBoundary layer information local to three longitudinal positions has been characterized for a 122 cm long acrylic cylinder with hemispherical endcaps, via analysis of stereo particle image velocimetry (PIV) measurements made during laterally oscillating motions and for steady, axisymmetric flow. No obvious turbulent flow structures or indications of boundary layer separation were observed at nonzero advance speeds, and skin friction coefficients were subsequently estimated for magnitude relative to the dynamic pressure associated with an axial flow speed of 0.25 m/s. Computational fluid dynamics (CFD) analysis is performed in commercial software to accompany the experimental measurements. Local skin friction coefficients are estimated and deviate, on average, from analytical solutions for zero gradient axisymmetric flows by around 22% and from the accompanying numerical solutions by around 4%. The effects of intermittent boundary layer compression and turbulence inhibition are readily observed for the oscillating cylinder, although vortex shedding is observed for some large amplitude, high frequency cases.

Analysis of Tangent Hyperbolic over a Vertical Porous Sheet of Carreau Fluid and Heat Transfer

The purpose of this study is to investigate the boundary layer of Carreau fluid and heat transfer over an exponentially stretching plate derived in a vertical porous with variable surface thermal flux. The partial differential equations that represent the momentum equation and heat equation are commuted into nonlinear ODEs by applying similarity transformations and results found numerically. The impact of several emerging dimensionless parameters labelled the Weissenberg number (We), the power-law index ( ), Velocity slip ( ), Thermal jump ( ), and Prandtl number ( ) on the velocity profile and heat transfer on the boundary layer are showed in detail. In more detail, also the influence of physical parameters on local skin friction and Sherwood number are studied. The shooting method with the explicit technique is used to find the solution and all results are illustrated graphically and numerically. We noted that by increasing power index, radiation parameter and velocity slip, the velocity profile increases, and the temperature profile decreases. Furthermore, it is deduced that rising the thermal radiation parameter reduces the local Nusselt number.

Heat and Mass Transport in Casson Nanofluid Flow over a 3-D Riga Plate with Cattaneo-Christov Double Flux: A Computational Modeling through Analytical Method

This work examines the non-Newtonian Cassonnanofluid’s three-dimensional flow and heat and mass transmission properties over a Riga plate. The Buongiorno nanofluid model, which is included in the present model, includes thermo-migration and random movement of nanoparticles. It also took into account the Cattaneo–Christov double flux processes in the mass and heat equations. The non-Newtonian Casson fluid model and the boundary layer approximation are included in the modeling of nonlinear partial differential systems. The homotopy technique was used to analytically solve the system’s governing equations. To examine the impact of dimensionless parameters on velocities, concentrations, temperatures, local Nusselt number, skin friction, and local Sherwood number, a parametric analysis was carried out. The velocity profile is augmented in this study as the size of the modified Hartmann number increases. The greater thermal radiative enhances the heat transport rate. When the mass relaxation parameter is used, the mass flux values start to decrease.

MHD flow and conductive heat transfer on a permeable stretching cylinder: Benchmark solutions

Research is conducted on parametric heat transfer and fluid flow solutions under the influencing factors of the porous stretching cylinder, magnetic field, curvature, permeable media, radiation, Joule heating, viscous dissipation, and heat generation/absorption. High non-linear coupled PDEs are solved and result in high non-linear coupled ODEs. The confluent hypergeometric function solves the energy equation with the PHF (prescribed heat flux) boundary condition. An analysis of physical parameters' effects is presented as tables and figures. According to the results, the variation of radiation parameters and Eckert numbers for the local Nusselt number in the injection area is negligible, while the variation of the heat source/sink parameters is considerable. The suction/injection and curvature parameters directly affect the local skin friction coefficient and Nusselt number. The porous stretching cylinder has a higher skin friction coefficient and heat transfer rate when compared to the porous stretching sheet.

A Numerical Assessment of Time-Dependent Magneto-Convective Thermal-Material Transfer over a Vertical Permeable Plate

The objective of this work is to investigate the influences of thermal radiation, heat generation, and buoyancy force on the time-dependent boundary layer (BL) flow across a vertical permeable plate. The fluid is unsteady, incompressible, viscous, and electrically insulating. The heat transfer mechanism happens due to free convection. The nondimensional partial differential equations of continuity, momentum, energy, and concentration are discussed using appropriate transformations. The impressions of thermal radiation and buoyancy forces are exposed in the energy and momentum equation, respectively. For numerical model, a set of nonlinear dimensionless partial differential equations can be solved using an explicit finite difference approach. The stability and convergence analyses are also established to complete the formulation of the model. The thermophysical effects of entering physical parameters on the flow, thermal, and material fields are analyzed. The variations in local and average skin friction, material, and heat transfer rates are also discussed for the physical interest. The analysis of the obtained findings is shown graphically, and relevant parameters pointedly prejudice the flow field. Studio Developer FORTRAN 6.2 and Tecplot 10.0 are applied to simulate the schematic model equations and graphical presentation numerically. The intensifying values of the magnetic field are affected decreasingly in the flow field. The temperature profiles decrease within the BL to increase the value of radiation parameters. The present study is on the consequences for petroleum engineering, agriculture engineering, extraction, purification processes, nuclear power plants, gas turbines, etc. To see the rationality of the present research, we compare these results and the results available in the literature with outstanding compatibility.

Viscous dissipation effect on unsteady magneto-convective heat-mass transport passing in a vertical porous plate with thermal radiation

The effects of radiative and viscous dissipation on the transfer of unsteady magnetic-conductive heat-mass across a vertically porous sheet is studied in this article. The non-dimensional ODEs are solved by applying the Finite Difference Method (FDM) through the MATLAB software numerically. The fluid temperature and velocity enhance for uplifting values of the Eckert number. Enhancing values of the transpiration parameter the velocity, concentration, and temperature distributions reduce. The local skin friction enhances about 9%, and 18% due to increase the Eckert number (0.5–3.0) and Dufour number (0.5–4.0), respectively and reduces 17%, 38%, and 31% due to increase Prandtl number (0.71–7.0), magnetic force parameter (0.5–3.0), and suction parameter (0.5–3.0), respectively. Enhancing values of the Eckert number (0.5–3.0) reduces the heat transfer rate by 40%. The increasing value of the Prandtl number (0.71–7.0) and the suction parameter (0.5–3.0) increases the heat transfer rate by 27% and 92%, respectively. With an increase in the values of the Schmidt number (0.22–0.67), the mass transfer rate increased by approximately 94%. At last, the numerical results of this paper has compared with the previously published paper. We noticed that the comparison has an excellent acceptance.

An effect of magnetohydrodynamic and radiation on axisymmetric flow of non-Newtonian fluid past a porous shrinking/stretching surface

The magnetohydrodynamic axisymmetric flow of Casson fluid over a nonlinear permeable shrinking or stretched surface is discussed in this article. Indeed, the heat transfer characteristics of an axisymmetric fluid across a non-linearly shrinking or stretching surface provided by a Casson fluid are examined analytically. Thermal radiationterm is incorporated into the equation for the temperature field. Through sufficient transformations, the aforementioned non-linear PDEs are turned into ODEs. The transformed equations are then solved analytically. And an incomplete gamma function is used to depict the temperature solution analytically. The temperature equation is transformed to an incomplete gamma functions using the Rosseland approximation for the radiation and solved analytically. To estimate mass transpiration analytically, the momentum equation is investigated. To acquire the analytical results, this mass transpiration is carried out in the analysis of heat transfer under the Navier slip condition. Graphical analysis can be used to assess important physical aspects like the magnetic field, Casson parameter, mass transpiration, radiation, and Prandtl number. Dual solutions for the velocity, temperature and skin friction were obtained. In fact,for higher Prandtl number, the temperature inside the boundary layer reduces. The resulting dual solution projects that local skin friction coefficient a escalates in the first branch solution and decelerates in the second branch solution with the increase in the magnetic parameter. additionally, efficiency is increased for higher values of thermal radiation.

Heat enhancement analysis of Maxwell fluid containing molybdenum disulfide and graphene nanoparticles in engine oil base fluid with isothermal wall temperature conditions

The goal of this paper is to examine the motion of a Maxwell nanofluid, including molybdenum disulfide and graphene nanoparticles, with ramped wall temperature (RWT) and isothermal wall temperature (IWT) at the barrier, by considering engine oil as the working fluids. The basic flow equation is converted to first-order ODEs by introducing the new variables. Using the numerical algorithm, the generated non-dimensional set of equations is computed using Runge–Kutta fourth-order method built-in function in MATLAB SOFTWARE with size . The iteration procedure was stopped until all of the nodes in the η-direction met the convergence condition 10−5. For confirmation of the results, the BVPh2 package is also applied. The physical parameters of interest such as local skin friction and Nusselt number are formulated and explained by tables. Lastly, the influence of molybdenum disulfide and graphene nanoscale on the convective heat and mass profiles of Maxwell ferrofluid is briefly explored. The novel part of this work is to examine the heat transfer analysis in engine oil base of Maxwell fluid with ramp and isothermal wall temperature conditions numerically, which has not been done in the published literature to date. Therefore, in the limiting sense, the present work is compared with published work.

Numerical Computation of Ag/Al2O3 Nanofluid over a Riga Plate with Heat Sink/Source and Non-Fourier Heat Flux Model

The main goal of the current research is to investigate the numerical computation of Ag/Al2O3 nanofluid over a Riga plate with injection/suction. The energy equation is formulated using the Cattaneo–Christov heat flux, non-linear thermal radiation, and heat sink/source. The leading equations are non-dimensionalized by employing the suitable transformations, and the numerical results are achieved by using the MATLAB bvp4c technique. The fluctuations of fluid flow and heat transfer on porosity, Forchheimer number, radiation, suction/injection, velocity slip, and nanoparticle volume fraction are investigated. Furthermore, the local skin friction coefficient (SFC), and local Nusselt number (LNN) are also addressed. Compared to previously reported studies, our computational results exactly coincided with the outcomes of the previous reports. We noticed that the Forchheimer number, suction/injection, slip, and nanoparticle volume fraction factors slow the velocity profile. We also noted that with improving rates of thermal radiation and convective heating, the heat transfer gradient decreases. The 40% presence of the Hartmann number leads to improved drag force by 14% and heat transfer gradient by 0.5%. The 20% presence of nanoparticle volume fraction leads to a decrement in heat transfer gradient for 21% of Ag nanoparticles and 18% of Al2O3 nanoparticles.

Diffusion Thermo and Chemical Reaction Effects on Magnetohydrodynamic Jeffrey Nanofluid Over an Inclined Vertical Plate in the Presence of Radiation Absorption and Constant Heat Source

This article investigates the Diffusion thermo and chemical reaction effects on the free convection heat and mass transfer flow of Jeffrey nanofluids (Cu and TiO2) over an inclined porous vertical plate embedded in a porous medium in the presence of radiation absorption and constant heat source under fluctuating boundary conditions. The plate is moved with a constant velocity U0, temperature and the concentration are assumed to be fluctuating with time harmonically from a constant mean at the plate. Perturbation technique is applied to solve the governing equations of the flow and pointed out the variations in velocity, temperature and concentration with the use of graphical presentations. The impact of several parameters on local skin friction, Nusselt number and Sherwood number is also noticed and discussed. It is concluded that the resultant velocity reduces with increasing Jeffrey parameter and Suction parameter, velocity and Temperature enhances with increasing Radiation absorption parameter. Also it is noticed that the solutal boundary layer thickness decreases with an increase in chemical reaction parameter. It is because chemical molecular diffusivity reduces for higher values of Kr.