Effect of Double Stratification on Free Convection in a Micropolar Fluid

2011 ◽  
Vol 133 (12) ◽  
Author(s):  
D. Srinivasacharya ◽  
Ch. RamReddy
Keyword(s):  
Mass Transfer ◽  
Free Convection ◽  
Heat And Mass Transfer ◽  
Micropolar Fluid ◽  
Double Stratification ◽  
Transfer Rates ◽  
Keller Box Method ◽  
Mass Fluxes ◽  
Special Cases ◽  
Good Agreement

This paper analyzes the flow and heat and mass transfer characteristics of the free convection on a vertical plate with uniform and constant heat and mass fluxes in a doubly stratified micropolar fluid. The nonlinear governing equations and their associated boundary conditions are initially cast into dimensionless forms by pseudosimilarity variables. The resulting system of equations is then solved numerically using the Keller-box method. The numerical results are compared and found to be in good agreement with previously published results on special cases of the problem. The obtained results are displayed graphically to illustrate the effect of the micropolar and stratification parameters on the dimensionless velocity, microrotation, wall temperature, and wall concentration. The numerical values of the skin friction, wall couple stress, and heat and mass transfer rates for different values of governing parameters are also tabulated.

scholarly journals Heat and Mass Transfer to a Cryosurface in Free Convection

1965 ◽  
Vol 87 (4) ◽  
pp. 499-506 ◽  
Author(s):  
R. F. Barron ◽  
L. S. Han
Keyword(s):  
Mass Transfer ◽  
Free Convection ◽  
Heat And Mass Transfer ◽  
Cryogenic Temperatures ◽  
Transfer Rates ◽  
Experimental Heat ◽  
Experimental Heat Transfer ◽  
Laminar And Turbulent Flow ◽  
And Diffusion ◽  
Good Agreement

Heat and mass transfer rates were measured experimentally and compared with analytically developed correlations for frost formation on a vertical flat plate in free convection. The plate was cooled internally to cryogenic temperatures (−310 F or liquid nitrogen temperatures), and both the laminar and turbulent flow regimes were investigated. In the laminar flow correlation, the effects of thermal diffusion and diffusion thermoeffect were included. The analytical and experimental heat transfer rates were in good agreement; however, the mass transfer results were affected by the presence of macromolecules of frost within the boundary layer.

Heat and mass transfer in non-Newtonian nanofluids over a non-isothermal stretching wall

2011 ◽  
Vol 225 (4) ◽  
pp. 155-163 ◽  
Author(s):  
Waqar A Khan ◽  
Rama Subba Reddy Gorla
Keyword(s):  
Mass Transfer ◽  
Skin Friction ◽  
Heat And Mass Transfer ◽  
Transfer Rates ◽  
Linear Ordinary Differential Equations ◽  
Layer Analysis ◽  
Special Cases ◽  
Nanoparticles Concentration ◽  
Method Effects ◽  
Good Agreement

A boundary layer analysis has been presented for the heat and mass transfer in non-Newtonian nanofluids over a stretching surface with prescribed wall temperature and surface nanoparticle concentration. A power-law model is used for non-Newtonian fluids whereas Brownian motion and thermophoresis effects are incorporated in the nanofluid model. A similarity transformation is used to reduce mass, momentum, thermal energy, and nanoparticles concentration equations into non-linear ordinary differential equations which are solved numerically by using a finite difference method. Effects of nanofluid parameters, suction/injection and temperature parameters, and generalized Pr and Le numbers on dimensionless functions, skin friction, local Nusselt and Sherwood numbers are shown graphically. The present results of skin friction and heat transfer rates are compared with published results for special cases and are found to be in good agreement.

scholarly journals Free convection in MHD micropolar fluid with radiation and chemical reaction effects

2014 ◽  
Vol 20 (2) ◽  
pp. 183-195 ◽  
Author(s):  
D. Srinivasacharya ◽  
Upendar Mendu
Keyword(s):  
Mass Transfer ◽  
Differential Equations ◽  
Free Convection ◽  
Heat And Mass Transfer ◽  
Chemical Reaction ◽  
Micropolar Fluid ◽  
Nonlinear Partial Differential Equations ◽  
Similarity Transformations ◽  
Variable Surface ◽  
Special Cases

In this paper, the effects of radiation and first order chemical reaction on free convection heat and mass transfer in a micropolar fluid is considered. A uniform magnetic field is applied normal to the plate. The plate is maintained with variable surface heat and mass fluxes. The governing nonlinear partial differential equations are transformed into a system of coupled nonlinear ordinary differential equations using similarity transformations and then solved numerically using the Keller-box method. The numerical results are compared and found to be in good agreement with previously published results as special cases of the present investigation. The dimensionless velocity, microrotation, temperature, concentration and heat and mass transfer rates are presented graphically for various values of coupling number, magnetic parameter, radiation parameter, chemical reaction parameter. The numerical values of the skin friction and wall couple stress for different values of governing parameters are also tabulated.

Computational analysis of heat and mass transfer in a micropolar fluid flow through a porous medium between permeable channel walls

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Sohail Ahmad ◽  
Muhammad Ashraf ◽  
Kashif Ali ◽  
Kottakkaran Sooppy Nisar
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Micropolar Fluid ◽  
Numerical Data ◽  
Substantial Effect ◽  
Linearization Method ◽  
Transfer Rates ◽  
Micropolar Fluid Flow ◽  
Permeable Walls ◽  
Model Equations

Abstract The present work numerically investigates the mass and heat transport flow of micropolar fluid in a channel having permeable walls. The appropriate boundary layer approximations are used to convert the system of flow model equations in ODEs, which are then numerically treated with the quasi-linearization method along with finite difference discretization. This technique creates an efficient way to solve the complex dynamical system of equations. A numerical data comparison is presented which assures the accuracy of our code. The outcomes of various problem parameters are portrayed via the graphs and tables. The concentration and temperature accelerate with the impacts of the Peclet numbers for the diffusion of mass and heat, respectively. It is also found that the porosity of the medium has a substantial effect on the skin friction but low effect on the heat and mass transfer rates. Our results may be beneficial in lubrication, foams and aerogels, micro emulsions, micro machines, polymer blends, alloys, etc.

scholarly journals Analysis of Heat and Mass Transfer for Second-Order Slip Flow on a Thin Needle Using a Two-Phase Nanofluid Model

Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1176
Author(s):  
Siti Nur Alwani Salleh ◽  
Norfifah Bachok ◽  
Fadzilah Md Ali ◽  
Norihan Md Arifin
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Slip Flow ◽  
Second Order ◽  
Two Phase ◽  
Specific Domain ◽  
Transfer Rates ◽  
Similarity Transformations ◽  
The Stability ◽  
Good Agreement

The present paper concentrates on the second-order slip flow over a moving thin needle in a nanofluid. The combined effects of thermophoresis and Brownian motion are considered to describe the heat and mass transfer performance of nanofluid. The resulting system of equations are obtained using similarity transformations and being executed in MATLAB software via bvp4c solver. The physical characteristics of embedded parameters on velocity, temperature, concentration, coefficient of skin friction, heat and mass transfer rates are demonstrated through a graphical approach and are discussed in detail. The obtained outcomes are validated with the existing works and are found to be in good agreement. It is shown that, for a specific domain of moving parameter, dual solutions are likely to exist. The stability analysis is performed to identify the stability of the solutions gained, and it is revealed that only one of them is numerically stable. The analysis indicated that the percentage of increment in the heat and mass transfer rates from no-slip to slip condition for both thin and thick surfaces of the needle ( a = 0.1 and a = 0.2 ) are 10.77 % and 12.56 % , respectively. Moreover, the symmetric behavior is noted for the graphs of reduced heat and mass transfer when the parameters N b and N t are the same.

Soret and dufour effects on MHD mixed convection heat and mass transfer in a micropolar fluid

2013 ◽  
Vol 3 (4) ◽  
Author(s):  
Darbhasayanam Srinivasacharya ◽  
Mendu Upendar
Keyword(s):  
Mass Transfer ◽  
Differential Equations ◽  
Mixed Convection ◽  
Heat And Mass Transfer ◽  
Micropolar Fluid ◽  
Nonlinear Partial Differential Equations ◽  
Skin Friction Coefficient ◽  
Soret And Dufour Effects ◽  
Similarity Transformations ◽  
Special Cases

AbstractThis paper analyzes the flow, heat and mass transfer characteristics of the mixed convection on a vertical plate in a micropolar fluid in the presence of Soret and Dufour effects. A uniform magnetic field of magnitude is applied normal to the plate. The governing nonlinear partial differential equations are transformed into a system of coupled nonlinear ordinary differential equations using similarity transformations and then solved numerically using the Keller-box method. The numerical results are compared and found to be in good agreement with previously published results as special cases of the present investigation. The rate of heat and mass transfer at the plate are presented graphically for various values of coupling number, magnetic parameter, Prandtl number, Schmidt number, Dufour and Soret numbers. In addition, the skin-friction coefficient, the wall couple stress are shown in a tabular form.

Thermophoretic and Nonlinear Convection in Non-Darcy Porous Medium

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
P. K. Kameswaran ◽  
P. Sibanda ◽  
M. K. Partha ◽  
P. V. S. N. Murthy
Keyword(s):  
Mass Transfer ◽  
Porous Medium ◽  
Heat And Mass Transfer ◽  
Fluid Velocity ◽  
Solute Concentration ◽  
Fluid Temperature ◽  
Nonlinear Convection ◽  
Transfer Rates ◽  
Special Cases ◽  
Layer Flow

In this paper, we study the effects of nonlinear convection and thermophoresis in steady boundary layer flow over a vertical impermeable wall in a non-Darcy porous medium. Both the fluid temperature and the solute concentration are assumed to be nonlinear while at the wall, both the temperature and concentration are maintained at a constant value. A similarity transformation was used to obtain a system of nonlinear ordinary differential equations, which were then solved numerically using the Matlab bvp4c solver. A comparison of the numerical results with previously published results for special cases shows a good agreement. The effects of the nonlinear temperature and concentration parameters on the velocity and heat and mass transfer are shown graphically. A representative sample of the results is presented showing the effects of thermophoresis on the fluid velocity and heat and mass transfer rates. It is found among other results, that the concentration profiles decreased with increasing values of the thermophoretic parameter.

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