Mixed convection dissipative viscous fluid flow over a rotating cone by way of variable viscosity and thermal conductivity

In this study, entropy generation analysis for Cu-water nanofluid mixed convective flow in an inclined channel occupied with a saturated porous media with Navier slip and convective boundary conditions is explored. The governing equations composed of equations of velocity and temperature are nondimensionalized and then solved utilizing the technique of homotopy analysis. Temperature and velocity profile expressions are acquired, which are then used to calculate the entropy produced in the scheme. The impacts of the corresponding fluid parameters are addressed in-depth on velocity, temperature, entropy generation, Bejan number,Nusselt number, skin friction, volume flow rate, and heat carried out by the fluid for 1% nanofluid concentration. Entropy has been observed to be minimal in all cases just above the channel center and maximum at the channel's bottom wall. Fluid friction-generated entropy has been discovered to have a higher influence on entropy generation. We also provide a comparative study with existing literature to validate our current results. K E Y W O R D Sconvective boundary, entropy, inclined channel, mixed convection, nanofluid, Navier slip

“…We solve the above coupled Equations and with the associated boundary conditions Equation using HAM . HAM is constructed on the notion of homotopy, a basic concept in topology.…”

Section: Homotopy Analysis Methodsmentioning

confidence: 99%

Second law analysis for mixed convection nanofluid flow in an inclined channel with convectively heated walls

Tlau

Ontela

2019

“…With foregoing assumptions and employing Boussinesq approximation boundary layer theory with thermal radiation and viscous dissipation effects, the transport equations of the hybrid nanofluid flow for momentum and energy transfer are established as follows 43,45,46

\frac{\partial (italicru)}{\partial x} + \frac{\partial (italicrw)}{\partial y} = 0,

\frac{\partial u}{\partial t} + u \frac{\partial u}{\partial x} + w \frac{\partial u}{\partial z} - \frac{v^{2}}{x} = \frac{1}{ρ_{hnf}} \frac{\partial}{\partial z} (μ_{hnf} \frac{\partial u}{\partial z}) - \frac{ν_{hnf}}{K} u + g {(β_{t})}_{hnf} (T - T_{\infty}) \cos θ *,

\frac{\partial v}{\partial t} + u \frac{\partial v}{\partial x} + w \frac{\partial v}{\partial z} + \frac{u v}{x} = \frac{1}{ρ_{hnf}} \frac{\partial}{\partial z} (μ_{hnf} \frac{\partial v}{\partial z}) - \frac{ν_{hnf}}{K} v,

\frac{\partial T}{\partial t} + u \frac{\partial T}{\partial x} + w \frac{\partial T}{\partial z} = \frac{1}{{(ρ c_{p})}_{hnf}} \frac{\partial}{\partial z} (k_{hnf} \frac{\partial T}{\partial z}) - \frac{1}{{(ρ c_{p})}_{hnf}} \frac{\partial q_{r}}{\partial z} + \frac{μ_{hnf}}{{(ρ c_{p})}_{hnf}} (][, (\frac{\partial u}{...}))

…”

Section: Mathematical Description Of the Problemmentioning

confidence: 99%

“…The initial values and boundary conditions best suited to the physical problem are as follows 43,46

\begin{matrix} left \\ t \leq 0 : & u = 0, v = 0, & w = 0, & T = T_{\infty} & \forall x, y, z \\ t > 0 : u = u_{0}, & v = \frac{1}{1 - ζ t *} Ω x \sin θ *, & w = 0, & T = T_{w} & a t z = 0 \\ u \to 0, v \to 0, & T \to T_{\infty} & a s & z \to \infty \end{matrix},

where

normalζ

is unsteadiness parameter and

t^{⁎} = (normalΩ normalsin θ^{⁎}) t

denotes dimensionless time.…”

Section: Mathematical Description Of the Problemmentioning

confidence: 99%

“…The temperature‐dependent viscosity

μ_{f}

and thermal conductivity

k_{f}

of the base fluid are given as follows 43 :

μ_{f} = μ_{0} (1 - α θ (ξ)), k_{f} = k_{0} (1 + ε θ (ξ)),

where

μ_{0}

and

k_{0}

are reference viscosity and thermal conductivity of base fluid, respectively,

ξ

is dimensionless variable,

θ

is dimensionless temperature,

α = ξ (T_{w} - T_{\infty})

is variable viscosity parameter (it should be noted that

α < 0

for gases and

α > 0

for liquids), and

ε = - ξ (T_{w} - T_{\infty})

is variable thermal conductivity parameter.…”

Section: Mathematical Description Of the Problemmentioning

confidence: 99%

“…Reddy and Chamkha 42 considered the effect of scale and shape nanoparticles on the MHD convectional flow of a nanofluid past a vertical cone. Malik et al 43 analyzed the impacts of temperature‐dependent viscosity and thermal conductivity on the flow and heat transfer characteristics of a viscous fluid over a rotating vertical cone. Their results indicated that the skin friction coefficient reduces with increasing values of variable viscosity parameter, whereas the heat transfer rate drops for increasing values of the Eckert number, variable viscosity, and variable thermal conductivity parameters.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Mixed convection hybrid nanofluids flow of MWCNTs–Al₂O₃/engine oil over a spinning cone with variable viscosity and thermal conductivity

Tulu

Ibrahim

2021

This work analyzed the effects of variable viscosity and thermal conductivity, with mixed convection, thermal radiation and viscous dissipation effects, on multiwalled carbon nanotubes (MWCNTs)–aluminum oxide (Al2O3)/engine oil hybrid nanofluid flow due to a vertically inverted spinning cone embedded in a porous medium. Using suitable similarity transformation, the boundary layer fluid flow governing equations are transformed into dimensionless systems of coupled nonlinear ordinary differential equations. Then, the solutions are obtained numerically employing the spectral relaxation method. The influences of involved parameters are examined, and the results are presented with graphs and tables. The obtained results disclose that both the tangential and azimuthal skin friction coefficients increase with increasing values of temperature‐dependent viscosity and mixed convection parameters. The local heat transfer rate reduces with increasing values of the Eckert number and variable thermal conductivity parameter, whereas it enhances with greater values of the thermal radiation parameter. Generally, hybrid nanofluids of (MWCNTs–Al2O3)/engine oil show better flow distributions with good stability of thermal properties than MWCNTs/engine oil and Al2O3/engine oil mono‐nanofluids.

Insight into the dynamics of micropolar fluid about a vertical cone when nonlinear thermal radiation is significant: The case of triple mixed convection

Patil

Shankar

2022

This novel research investigates the nonlinear triple diffusive combined convective micropolar liquid flow past a vertical cone in the presence of nonlinear thermal radiation, cross-diffusion, and a convective boundary condition. We aim to analyze this present problem using nonsimilar transformations. This report presents the significance of nonlinear mixed convection, energy flux due to the concentration gradient, and mass flux due to the temperature gradient and nonlinear thermal radiation in the dynamics of the fluid subject with micropolar fluid is presented. The differential equations defining the boundary-layer parameters are then transformed into dimensionless view, taking into account the nonsimilar transformation. Furthermore, the method of quasilinearization and implicit finite difference approximation is used to work out the nondimensional governing equations for the solution. The velocity pattern diminishes, while dimensionless temperature and concentration distributions enhance with growing values of microrotation parameter. Furthermore, species concentrations of the fluid increase with increasing Soret effect values, while opposite results appear for mass transfer rates. Also, drag coefficient