Non-isothermal Flat Plate Research Articles

Heat Transfer Analysis of the MHD Stagnation Point Flow of a Non‐Newtonian Tangent Hyperbolic Hybrid Nanofluid past a Non‐Isothermal Flat Plate with Thermal Radiation Effect

Heat transfer phenomena are used in a variety of industries, including chemical devices, shipbuilding, power plants, electronic devices, and medicinal plants. Propylene glycol, engine oil, water, and ethylene glycol are common single‐phase heat transfer liquids used in a variety of industries, including chemical process industries and thermal power plants. Therefore, the authors are interested in investigating the magnetohydrodynamic flow of a water‐based hybrid nanofluid containing ferrous and graphene oxide nanoparticles past a flat plate. The stagnation points, as well as the effects of magnetic field and thermal radiation are taken into account in this analysis. The non‐Newtonian tangent hyperbolic flow, which is laminar and incompressible, is also considered to investigate the non‐Newtonian behavior of the hybrid nanofluid flow. The proposed model has been solved analytically with the help of HAM. The convergence of HAM is shown with the help of figure. The hydrothermal characteristics of hybrid nanofluid flow past a nonisothermal flat plate at a stagnation point are affected by the necessary parameters. The results show that the boosting volume fractions of the ferrous and graphene oxide nanoparticles have significantly reduced the velocity field, while the thermal field has increased with the augmenting volume fractions of the ferrous and graphene oxide nanoparticles. The increasing power‐law index has augmented the viscosity of the non‐Newtonian hybrid nanofluid flow due to which the velocity field escalated. However, this impact is opposite for the thermal field. Due to the direct relation between the Weissenberg number and relaxation time, the greater Weissenberg number has reduced the velocity profile, while increased the thermal field.

Analytic study of MHD flow and boundary layer control over a nonisothermal flat plate

Analytic study of MHD flow and boundary layer control over a nonisothermal flat plate

MHD Boundary Layer Flow and Heat Transfer over a Moving Non-Isothermal Flat Plate

The steady two-dimensional laminar incompressible electrically conducting viscous fluid on a moving flat plate in the presence of a transverse magnetic field is studied. Taking suitable similarity variables, we transform the governing boundary layer equations into ordinary differential equations and solve them numerically by standard techniques. The effects of moving and magnetic parameters, Prandtl number, and Eckert number on the velocity and temperature as well as on the skin-friction coefficient and Nusselt number are studied.

Optimal aspect ratios for non-isothermal flat plate solar collectors for air heating

In the present work, the dimensionless model developed and validated by Baritto and Bracamonte (2012) for thermal behavior of flat plate solar collectors without glass cover was improved by adding the entropy balance equation in a dimensionless form. The model was solved for a wide range of aspect ratios and mass flow numbers. A parametric study was developed and thermodynamically optimal configurations were identified. A set of equations were fitted to reproduce the results and a straight forward method is proposed for the estimation of optimal aspect ratios as functions of the mass flow number and the outlet temperature, which are, in most of cases, requirements for practical applications.

A dimensionless model for the outlet temperature of a nonisothermal flat plate solar collector for air heating

The numerical model proposed by Baritto (2010) for the prediction of temperature distribution in a flat plate solar air heater is presented in dimensionless form and solved for a wide range of turbulent flow operating conditions. A parametric study is performed and the outlet temperature is proposed as a function of the aspect ratios and the mass flow number. The proposed equation shows good agreement with experimental data.

A Numerical Analysis on the Freeze Coating of a Non-Isothermal Flat Plate with a Binary Alloy

A numerical analysis on the freeze coating process of a non-isothermal finite dimensional plate with a binary alloy is performed to investigate the growth and decay behavior of the solid and the mushy layer of the freeze coat and a complete procedure to calculate the process is obtained in this study. The continuously varying solid and mushy layers are immobilized by a coordinate transform and the resulting governing differential equations are solved by a finite difference technique. To account for the latent heat release and property change during solidification, proper phase change models are adopted. And the convection in the liquid melt is modeled as an appropriate heat transfer boundary condition at the liquid/mushy interface. The present results are compared with analytic solutions derived for the freeze coating of infinite dimensional plates and the discrepancy is found to be less than 0.5 percent in relative magnitude for all simulation cases. In addition the conservation of thermal energy is checked. The results show that the freeze coat grows proportional to the 1.2 square of axial position as predicted by analytic solutions ar first. But after the short period of initial growth, the growth rate of the freeze coat gradually decreases and finally the freeze coat starts to decay. The effects of various non-dimensional processing parameters on the behavior of freeze coat are also investigated.

Effect of suction/injection on the free convective heat transfer in a micropolar fluid from a nonisothermal flat plate under non-uniform gravity

The effect of suction or injection on the laminar free convective heat transfer of a micropolar fluid from a non-isothermal flat plate under non-uniform gravity has been considered. Two types of boundary conditions are prescribed for the micro-rotation on the surface. Also, several specific forms for the temperature distributions of the plate are considered. For these instances the velocity, micro-rotation, temperature, skin friction and heat transfer rate are presented.

Free convection flow on a nonisothermal flat plate under nonuniform gravity

In this paper, we present results obtained by using a numerical procedure for the free convection flow along a rotating nonisothermal plate subject to a nonuniform gravity field. Several specific forms for the temperature distributions of the plate are considered. For these instances the skin-friction and heat transfer rate on the wall at selected values of the distance from the leading edge and for some values of Prandtl numbers are presented. The method employed is shown to be very accurate in comparison with previous solutions.

Some Effects of Variable Surface Temperature on Heat Transfer to a Partially Porous Flat Plate

Based on a simple enthalpy thickness approach, results are presented for laminar and turbulent heat transfer to a partially porous, nonisothermal flat plate. The model employed accounts for thermodynamic coupling between the boundary layer and porous wall heat transfer problems, and is expanded to include consideration of axial heat conduction along the wall. The results indicate that partial injection can be expected to produce a highly nonisothermal surface, which in turn causes the external Stanton number distribution to differ markedly from that predicted previously for assumed isothermal wall conditions. The boundary layer prediction technique is shown to be in reasonably good agreement with recent analytical and experimental results reported in the literature.

Effect of Streamwise Heat Conduction on Heat Transfer from a Nonisothermal Flat Plate at Low Prandtl Numbers

The effect of streamwise heat conduction on heat transfer from a flat plate is studied at low Prandtl numbers. The surface temperature of the plate is assumed to vary according to a power law with the longitudinal distance. The analysis is performed as a perturbation of the classical boundary-layer theory. The resulting similar energy equations are solved for small Prandtl number by using the method of matched asymptotic expansions.

Heat transfer on a nonisothermal flat plate with a laminar boundary layer

Heat transfer on a nonisothermal flat plate with a laminar boundary layer

A Summary of Experiments on Turbulent Heat Transfer From a Nonisothermal Flat Plate

The results of an extensive experimental investigation of heat transfer to a turbulent incompressible boundary layer from a nonisothermal flat plate are summarized. Data presented extend the range of low-Mach-number confirmation of the von Karman analogy to Reynolds numbers of 4 × 106 for an isothermal plate. Data for a step wall-temperature distribution confirm experimentally the preferable expression for this important superposition kernel case. Data from a variety of other examples confirm the use of the superposition theories to predict heat transfer from nonisothermal surfaces.

Investigation of the Variation of Point Unit Heat-Transfer Coefficients for Laminar Flow Over an Inclined Flat Plate

Abstract Many applications of heat-transfer phenomena by forced convection require a knowledge of heat transfer from simple geometric bodies like the flat plate. Investigations of the flat plate have been limited, in general, to studies of isothermal plates of 0-deg angle of incidence and in laminar flow. The amount of data concerning investigations on turbulent flow, nonisothermal plates or inclined plates is quite small. It is the intent of this paper to provide information on the heat transfer from a nonisothermal inclined flat plate in laminar flow. It is shown herein that forced-convection heat-transfer data for an inclined nonisothermal flat plate with a constant specific rate of heat flow can be correlated and represented by an equation of the type (1) Nu x Re L = C ( x L ) n for laminar flow. It is further shown that this equation is similar in slope to the theoretical equation of the type (2) Nu x Re L = C 2 ( x L ) m + 1 2 for an isothermal plate in laminar flow, but is larger by 30 per cent in absolute value. This variance can be partly explained by an analysis of the behavior of a nonisothermal plate as opposed to an isothermal one, but this analysis leaves much to be desired, so that the full explanation is at present unknown.