The microtube heat sink with tangential impingement jet and variable fluid properties

This paper investigates the energy exchanges associated with the half-trace of the velocity fluctuation correlation tensor in a strongly anisothermal low Mach fully developed turbulent channel flow. The study is based on direct numerical simulations of the channel within the low Mach number hypothesis and without gravity. The overall flow behaviour is governed by the variable fluid properties. The temperature of the two channel walls are imposed at 293 K and 586 K to generate the temperature gradient. The mean friction Reynolds number of the simulation is 180. The analysis is carried out in the spatial and spectral domains. The spatial and spectral studies use the same decomposition of the terms of the evolution equation of the half-trace of the velocity fluctuation correlation tensor. The importance of each term of the decomposition in the energy exchanges is assessed. This lets us identify the terms associated with variations or fluctuations of the fluid properties that are not negligible. Then, the behaviour of the terms is investigated. The spectral energy exchanges are first discussed in the incompressible case since the analysis is not present in the literature with the decomposition used in this study. The modification of the energy exchanges by the temperature gradient is then investigated in the spatial and spectral domains. The temperature gradient generates an asymmetry between the two sides of the channel. The asymmetry can in a large part be explained by the combined effect of the mean local variations of the fluid properties, combined with a Reynolds number effect.

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Unsteady boundary layer flow of a nanofluid over a stretching sheet with variable fluid properties in the presence of thermal radiation

Thermophysics and Aeromechanics ◽

10.1134/s0869864316030100 ◽

2016 ◽

Vol 23 (3) ◽

pp. 403-413 ◽

Cited By ~ 6

Author(s):

Mitiku Daba ◽

P. Devaraj

Keyword(s):

Boundary Layer ◽

Thermal Radiation ◽

Boundary Layer Flow ◽

Stretching Sheet ◽

Unsteady Boundary Layer ◽

Variable Fluid Properties ◽

Fluid Properties ◽

Layer Flow

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Comment on the paper “Mixed convection heat transfer over a non-linear stretching surface with variable fluid properties by K.V. Prasad, K. Vajravelu and P.S. Datti, International Journal of Non-linear Mechanics 45, 2010, pp. 320–330”

International Journal of Non-Linear Mechanics ◽

10.1016/j.ijnonlinmec.2015.01.001 ◽

2017 ◽

Vol 93 ◽

pp. 126-127 ◽

Cited By ~ 1

Author(s):

Asterios Pantokratoras

Keyword(s):

Heat Transfer ◽

Mixed Convection ◽

Convection Heat Transfer ◽

Convection Heat ◽

Stretching Surface ◽

Variable Fluid Properties ◽

Non Linear ◽

Fluid Properties ◽

Mixed Convection Heat Transfer ◽

Non Linear Mechanics

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Influence of Hall Current on MHD Flow and Heat Transfer over a slender stretching sheet in the presence of variable fluid properties

Communications in Numerical Analysis ◽

10.5899/2016/cna-00251 ◽

2016 ◽

Vol 2016 (1) ◽

pp. 17-36 ◽

Cited By ~ 7

Author(s):

K. Vajravelu ◽

K. V. Prasad ◽

Hanumesh Vaidya

Keyword(s):

Heat Transfer ◽

Stretching Sheet ◽

Hall Current ◽

Mhd Flow ◽

Flow And Heat Transfer ◽

Variable Fluid Properties ◽

Fluid Properties

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Analysis of MHD Forced Convective Flow of Variable Fluid Properties over a Saturated Porous Medium with Thermal Radiation Effect

International Frontier Science Letters ◽

10.18052/www.scipress.com/ifsl.9.47 ◽

2016 ◽

Vol 9 ◽

pp. 47-65 ◽

Cited By ~ 1

Author(s):

Kolawole Sunday Adegbie ◽

Adeyemi Isaiah Fagbade

Keyword(s):

Porous Medium ◽

Heat Loss ◽

Convective Flow ◽

Radiative Heat ◽

Saturated Porous Medium ◽

Fluid Velocity ◽

Radiative Heat Loss ◽

Variable Fluid Properties ◽

Fluid Properties ◽

Forced Convective Flow

The present paper addresses the problem of MHD forced convective flow in a fluid saturated porous medium with Brinkman-Forchheimer model, which is an important physical phenomena in engineering applications. The paper extends the previous models to account for effects of variable fluid properties on the forced convective flow through a porous medium in the presence of radiative heat loss using bivariate spectral relaxation method (BSRM). The dynamic viscosity and thermal conductivity of the newtonian fluid are assumed to vary linearly respectively, with temperature whereas the contribution of thermal radiative heat loss is based on Rosseland diffussion approximation. The flow model is described and expressed in form of a highly coupled nonlinear system of partial differential equations. The method of solution BSRM as proposed by Motsa [25] seeks to decouple the original system of PDEs to form a sequence of equations that can be solved in a computationally efficient manner. BSRM is an approach that applies spectral collocation independently in all underlying independent variable is executed to obtain approximate solutions of the problem. The proposed algorithm is supposed to be a very accurate, convergent and very effective in generating numerical results. The results obtained show a significant effects of the flow control parameters on the fluid velocity and temperature respectively. Consequently, the wall shear stress and local heat transfer rate of the present paper are compared with the available results in literatures. Remarkable impacts and a good agreement are found.

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