D. S. Martínez^†, J. P. Solano, J. Pérez, A. Viedma

Frontiers in Heat and Mass Transfer, Vol.2, No.3, pp. 1-10, 2011, DOI:10.5098/hmt.v2.3.3002

Abstract Non-Newtonian flow and heat transfer in tubes of heat exchangers with reciprocating insert devices have been numerically investigated. The heat exchanger is mechanically assisted by a reciprocating cylinder, which moves the scraping rods inserted in the tubes. An array of semi-circular elements is mounted on each rod, with a pitch p=5D. These elements fit the internal diameter of the tubes. During the reciprocating motion, they scrape the inner tube wall, avoiding fouling. Additionally, the movement of the inserted device generates macroscopic displacements of the flow, which continuously mix core regions with peripheral flow. A power law model with temperature dependent… More >

Cheng Han^1,*, Zhengguang Xu^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 515-536, 2024, DOI:10.32604/cmes.2023.043464

Abstract A prediction framework based on the evolution of pattern motion probability density is proposed for the output prediction and estimation problem of non-Newtonian mechanical systems, assuming that the system satisfies the generalized Lipschitz condition. As a complex nonlinear system primarily governed by statistical laws rather than Newtonian mechanics, the output of non-Newtonian mechanics systems is difficult to describe through deterministic variables such as state variables, which poses difficulties in predicting and estimating the system’s output. In this article, the temporal variation of the system is described by constructing pattern category variables, which are non-deterministic variables. Since pattern category variables have… More >

Swetha Lanka¹, Venkata Subrahmanyam Sajja^1,*, Dhaneshwar Prasad²

Frontiers in Heat and Mass Transfer, Vol.21, pp. 385-405, 2023, DOI:10.32604/fhmt.2023.042544

Abstract An attempt is made to analyse some lubrication characteristics of rigid cylindrical asymmetric rollers under adiabatic and isothermal boundaries with rolling and sliding motion lubricated by a non-Newtonian incompressible Bingham plastic fluid under the behaviour of line contact. Here the lower surface is considered to move quicker than that of the upper surface; and the Roelands viscosity model is considered and assumed to depend upon the fluid pressure and the mean film temperature. The governing equations for fluid flow such as equations of motion with continuity and the momentum energy equation are solved using Runge-Kutta forth order and MATLAB is… More >

R.R. Kairi^a, Ch. RamReddy^b,*

Frontiers in Heat and Mass Transfer, Vol.6, pp. 1-7, 2015, DOI:10.5098/hmt.6.6

Abstract In this paper, we investigated the influence of melting on mixed convection heat and mass transfer from the vertical flat plate in a non-Newtonian nanofluid saturated porous medium. The wall and the ambient medium are maintained at constant, but different, levels of temperature and concentration. The Ostwald–de Waele power-law model is used to characterize the non-Newtonian nanofluid behavior. A similarity solution for the transformed governing equations is obtained. The numerical computation is carried out for various values of the non-dimensional physical parameters. The variation of temperature, concentration, heat and mass transfer coefficients with the power-law index, mixed convection parameter, melting… More >

CH. Amanulla^a,b , N. Nagendra^a,1 , M. Surya Narayana Reddy^b , A. Subba Rao^a , O. Anwar Bég^c

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-13, 2017, DOI:10.5098/hmt.8.29

Abstract In this article, the heat, momentum and mass (species) transfer in external boundary layer flow of Casson nanofluid from an isothermal sphere surface is studied theoretically. The effects of Brownian motion and thermophoresis are incorporated in the model in the presence of both heat and nanoparticle mass transfer. The governing partial differential equations (PDEs) are transformed into highly nonlinear, coupled, multi-degree non-similar partial differential equations consisting of the momentum, energy and concentration equations via appropriate non-similarity transformations. These transformed conservation equations are solved subject to appropriate boundary conditions with a second order accurate finite difference method of the implicit type.… More >

Z. Iqbal, Ehtsham Azhar^* , E. N. Maraj, Bilal Ahmad

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-7, 2017, DOI:10.5098/hmt.8.25

Abstract Present investigation represent the study of Cattaneo-Christov heat flux model on boundary layer flow of hyperbolic tangent fluid which is generalized non-Newtonian fluid model over a continuously moving porous surface with a parallel free stream velocity. Mathematical formulation is completed in the presence of Magneto-hydrodynamics (MHD). Suitable relations transform the partial differential equations into the ordinary differential equations. Nonlinear flow analysis is computed and velocity and temperature profiles are obtained by shooting algorithm. Graphs are plotted to analyze the behavior of various involved physical parameters. Furthermore both type of flows Sakaidis ( λ = 1) and Blasius flow (0 ≤… More >

Driss Achemlal^a,† , Mohammed Sriti^b , Mohamed El Haroui^b , Elyazid Flilihi^b , Mounir Kriraa^a

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-10, 2017, DOI:10.5098/hmt.9.34

Abstract In this paper we study the combined free convection, due to thermal and species diffusion, of a viscous incompressible non Newtonian fluid over a vertical plate embedded in a saturated porous medium with three thermal states of the surface and a constant concentration in the presence of a chemical reaction. The effect of temperature dependent viscosity is also investigated. The Ostwald-de Waele power-law model is used to characterize the non-Newtonian fluid behavior. The governing boundary layer equations along with the boundary conditions are first cast into a dimensionless form by a unique similarity transformation and the resulting coupled differential equations… More >

A. Subba Rao^a,*, L. Nagaraja^a,b, M. Sudhakar Reddy^a , M. Surya Narayana Reddy^b

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-11, 2017, DOI:10.5098/hmt.9.17

Abstract This article investigates the theoretical steady magneto hydrodynamic heat flow of incompressible non-Newtonian Tangent Hyperbolic fluid flow over a sphere with Soret and Dufour effects. The governing coupled non-linear partial differential equations are reduced to non-similarity boundary layer equations using appropriate transformation and then solved using the finite difference Keller-Box method. The effect of various flow parameters on the velocity, temperature and concentration are analyzed and presented graphically. More >

A. Subba Rao^a,* , V. Ramachandra Prasad^a , P. Rajendra^a , M. Sasikala^a , O. Anwar Beg^b

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-9, 2017, DOI:10.5098/hmt.9.2

Abstract In this article, we investigate the nonlinear steady state boundary layer flow and heat transfer of an incompressible Jeffery non-Newtonian fluid from a permeable horizontal isothermal cylinder. The transformed conservation equations are solved numerically subject to physically appropriate boundary conditions using a versatile, implicit, finite-difference technique. The numerical code is validated with previous studies. The influence of a number of emerging non-dimensional parameters, namely with Deborah number (De), surface suction parameter (S), Prandtl number (Pr), ratio of relaxation to retardation times (λ) and dimensionless tangential coordinate (ξ) on velocity and temperature evolution in the boundary layer regime are examined in… More >

Astick Banerjee^a , Aurang Zaib^b , Krishnendu Bhattacharyya^c,* , S.K. Mahato^d

Frontiers in Heat and Mass Transfer, Vol.10, pp. 1-8, 2018, DOI:10.5098/hmt.10.30

Abstract The magnetohydrodynamic (MHD) mixed convection heat transfer in a non-Newtonian Powell-Erying fluid flow due to an exponentially shrinking porous sheet is investigated. Both assisting and opposing flows are considered. After use of the suitable transformations, the governing equations become non-similar ODEs. Numerical computations of resulting equations are obtained by very efficient shooting method for several values of involved parameters. The results exhibit that dual non-similar solutions can be found only when some amount of fluid mass is sucked from the flow field through the porous sheet. Many important results on the effect of external magnetic field on mixed convective flow… More >