scholarly journals Rivlin-Ericksen Fluid in Tube of Varying Cross-section with Mass and Heat Transfer

2002 ◽  
Vol 57 (11) ◽  
pp. 863-873 ◽  
Author(s):  
Nabil T. El Dabe ◽  
Galal M. Moatimid ◽  
Hoda S. M. Ali
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Cross Section ◽  
Perturbation Technique ◽  
Equations Of Motion ◽  
Steady Motion ◽  
Physical Parameters ◽  
Mass And Heat Transfer

In this paper, the problem of heat and mass transfer due to the steady motion of a Rivlin- Ericksen fluid in tubes of varying cross-section is considered. Suction at tube walls is taken into account. Under the assumption that the deformations of the boundaries are small, the equations of motion have been solved by using a perturbation technique. The temperature and concentration distributions are obtained. The effects of various physical parameters are discussed. The Nusselt and Sherwood numbers are obtained. A set of figures for a quantitative illustration is presented.

Non-Darcy Couette flow through a porous medium of magnetohydro-dynamic visco-elastic fluid with heat and mass transfer

2005 ◽  
Vol 83 (12) ◽  
pp. 1243-1265 ◽  
Author(s):  
Nabil TM Eldabe ◽  
S N Sallam
Keyword(s):  
Mass Transfer ◽  
Porous Medium ◽  
Skin Friction ◽  
Heat And Mass Transfer ◽  
Perturbation Technique ◽  
Equations Of Motion ◽  
Transverse Magnetic ◽  
Physical Parameters ◽  
Parallel Plates ◽  
Elastic Fluid

We analyze the steady magnetohydrodynamic flow of an incompressible electrically conducting visco-elastic fluid through a porous medium between two porous parallel plates under the influence of a transverse magnetic field. We obtain an exact solution for the Brinkman–Forchheimer extension of Darcy's momentum equation for flow. We solve the equations of motion with a perturbation technique under the assumption that the Forchheimer number Fs = bν/u0 is small. We analyze heat and mass transfer in porous media. We obtain the skin friction τw, the Nusselt number Nu, and the Sherwood number Sh. Our numerical results show the effects of the physical parameters of our problem on the fluid flow as well as on the heat and mass transfer, on the skin friction, and on the rates of heat and mass transfer. PACS No.: 47.65.+a

scholarly journals Influence of Hall Current and Thermal Radiation on MHD Convective Heat and Mass Transfer in a Rotating Porous Channel with Chemical Reaction

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Dulal Pal ◽  
Babulal Talukdar
Keyword(s):  
Magnetic Field ◽  
Mass Transfer ◽  
Thermal Radiation ◽  
Heat And Mass Transfer ◽  
Hall Current ◽  
Perturbation Technique ◽  
Porous Channel ◽  
Physical Parameters ◽  
Shear Stresses ◽  
Resultant Velocity

A theoretical study is carried out to obtain an analytic solution of heat and mass transfer in a vertical porous channel with rotation and Hall current. A constant suction and injection is applied to the two insulating porous plates. A strong magnetic field is applied in the transverse direction. The entire system rotates with uniform angular velocity Ω about the axis normal to the plates. The governing equations are solved by perturbation technique to obtain the analytical results for velocity, temperature, and concentration fields and shear stresses. The steady and unsteady resultant velocities along with the phase differences for various values of physical parameters are discussed in detail. The effects of rotation, buoyancy force, magnetic field, thermal radiation, and heat generation parameters on resultant velocity, temperature, and concentration fields are analyzed.

Changed Heat and Mass Transfer Evaluation of a Gas-to-Gas Type Membrane Humidifier by Mass Collection

2010 ◽  
Author(s):  
ByungJun Kim ◽  
SangSeok Yu ◽  
YoungDuk Lee ◽  
KookYoung Ahn
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Steady State ◽  
Heat And Mass Transfer ◽  
Humidity Sensor ◽  
Transient State ◽  
Air Flow Rate ◽  
Dry Air ◽  
Mass And Heat Transfer ◽  
Mass Collection

In this paper, a technique of the humidity measurement is developed to identify the performance of membrane humidifier. The technique is designed to measure the performance of membrane humidifier during steady state and transient state. In particular, the measurement technique is very useful to understand dynamic behavior of humidifier because the response of commercial humidity sensor is too slow to capture the transient response of mass and heat transfer through the membrane. Accordingly, the heat and mass transfer characteristics of membrane humidifier are figured out with the experimental analysis. The parameters used in experiment are dry air pressure, humid air temperature and dry air flow rate.

scholarly journals Revisiting the Role of Mass and Heat Transfer in Gas–Solid Catalytic Reactions

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1599
Author(s):  
Riccardo Tesser ◽  
Elio Santacesaria
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Kinetic Studies ◽  
Packed Bed ◽  
Catalytic Reactions ◽  
Catalytic Reactors ◽  
Tremendous Progress ◽  
Mass And Heat Transfer ◽  
Energy Balances

The tremendous progress in the computing power of modern computers has in the last 20 years favored the use of numerical methods for solving complex problems in the field of chemical kinetics and of reactor simulations considering also the effect of mass and heat transfer. Many classical textbooks dealing with the topic have, therefore, become quite obsolete. The present work is a review of the role that heat and mass transfer have in the kinetic studies of gas–solid catalytic reactions. The scope was to collect in a relatively short document the necessary knowledge for a correct simulation of gas–solid catalytic reactors. The first part of the review deals with the most reliable approach to the description of the heat and mass transfer outside and inside a single catalytic particle. Some different examples of calculations allow for an easier understanding of the described methods. The second part of the review is related to the heat and mass transfer in packed bed reactors, considering the macroscopic gradients that derive from the solution of mass and energy balances on the whole reactor. Moreover, in this second part, some examples of calculations, applied to chemical reactions of industrial interest, are reported for a better understanding of the systems studied.

scholarly journals Twente mass and heat transfer water tunnel: Temperature controlled turbulent multiphase channel flow with heat and mass transfer

2019 ◽  
Vol 90 (7) ◽  
pp. 075117
Author(s):  
Biljana Gvozdić ◽  
On-Yu Dung ◽  
Dennis P. M. van Gils ◽  
Gert-Wim H. Bruggert ◽  
Elise Alméras ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Channel Flow ◽  
Water Tunnel ◽  
Mass And Heat Transfer ◽  
Temperature Controlled

scholarly journals MHD Peristaltic Transport of Bingham Blood Fluid with Heat and Mass Transfer Through a Non-Uniform Channel

2020 ◽  
Vol 77 (2) ◽  
pp. 145-159
Author(s):  
Nabil Tawfik Eldabe ◽  
Mohamed Abouzeid ◽  
Hamida A Shawky
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Perturbation Technique ◽  
Physical Parameters ◽  
Soret And Dufour Effects ◽  
Long Wavelength ◽  
Electrically Conducting ◽  
Linear Partial Differential Equations ◽  
Uniform Channel ◽  
Homotopy Perturbation Technique

In the present work, the flow of non-Newtonian Bingham blood fluid through non-uniform channel is investigated. The fluid is electrically conducting, and the external uniform magnetic field is applied on this motion. The heat and mass transfer are taken in consideration, so, Soret and Dufour effects are studied. The problem is modulated mathematically by a system of non-linear partial differential equations which govern the velocity, temperature and concentration distributions. The system of these equations is simplified under the assumptions of long wavelength and low Reynolds number, then it is solved analytically by using homotopy perturbation technique. These distributions are obtained as a function of the physical parameters of the problem. The effects of these parameters on the obtained solutions are discussed numerically and illustrated graphically through a set of figures. These parameters play an important role to control the values of solutions. The used Bingham model is applicable for the physiological transportation of blood in arteries.

scholarly journals MHD Heat and Mass Transfer of Chemical Reaction Fluid Flow over a Moving Vertical Plate in Presence of Heat Source with Convective Surface Boundary Condition

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
B. R. Rout ◽  
S. K. Parida ◽  
S. Panda
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Boundary Condition ◽  
Heat Source ◽  
Heat And Mass Transfer ◽  
Chemical Reaction ◽  
Internal Heat ◽  
Integration Scheme ◽  
Physical Parameters ◽  
Surface Boundary

This paper aims to investigate the influence of chemical reaction and the combined effects of internal heat generation and a convective boundary condition on the laminar boundary layer MHD heat and mass transfer flow over a moving vertical flat plate. The lower surface of the plate is in contact with a hot fluid while the stream of cold fluid flows over the upper surface with heat source and chemical reaction. The basic equations governing the flow, heat transfer, and concentration are reduced to a set of ordinary differential equations by using appropriate transformation for variables and solved numerically by Runge-Kutta fourth-order integration scheme in association with shooting method. The effects of physical parameters on the velocity, temperature, and concentration profiles are illustrated graphically. A table recording the values of skin friction, heat transfer, and mass transfer at the plate is also presented. The discussion focuses on the physical interpretation of the results as well as their comparison with previous studies which shows good agreement as a special case of the problem.

scholarly journals Study on Electrohydrodynamic Rayleigh-Taylor Instability with Heat and Mass Transfer

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Mukesh Kumar Awasthi ◽  
Vineet K. Srivastava
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Electric Field ◽  
Heat And Mass Transfer ◽  
Taylor Instability ◽  
Wave Number ◽  
Physical Parameters ◽  
Tangential Electric Field ◽  
Rayleigh Taylor Instability ◽  
The Stability

The linear analysis of Rayleigh-Taylor instability of the interface between two viscous and dielectric fluids in the presence of a tangential electric field has been carried out when there is heat and mass transfer across the interface. In our earlier work, the viscous potential flow analysis of Rayleigh-Taylor instability in presence of tangential electric field was studied. Here, we use another irrotational theory in which the discontinuities in the irrotational tangential velocity and shear stress are eliminated in the global energy balance. Stability criterion is given by critical value of applied electric field as well as critical wave number. Various graphs have been drawn to show the effect of various physical parameters such as electric field, heat transfer coefficient, and vapour fraction on the stability of the system. It has been observed that heat transfer and electric field both have stabilizing effect on the stability of the system.

Hybrid Modeling of Modified Mathematical Model for Gas Phase Olefine in Fluidized Bed Catalyst Reactors Using Artificial Neural Networks

2009 ◽  
Vol 4 (1) ◽  
Author(s):  
Ahmmed Saadi Ibrehem
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Fluidized Bed ◽  
Hybrid Model ◽  
Operating Conditions ◽  
Transfer Coefficients ◽  
Mass And Heat Transfer ◽  
Artificial Neural

The complex flow patterns induced in fluidized bed catalytic reactors and the competing parameters affecting the mass and heat transfer characteristics makes the design of such reactors a challenging task to accomplish. The models of such a process rely heavily on predictive empirical correlations for mass and heat transfer coefficients. Unfortunately, published empirical based correlations have the common shortcoming of low-prediction efficiency compared with experimental data. In this work, an artificial neural network approach is used to capture the reactor characteristics in terms of heat and mass transfer based on published experimental data. The developed ANN-based heat and mass transfer coefficients relations were used in a conventional FCR model and simulated under industrial operating conditions. The hybrid model predictions of the melt-flow index and the emulsion temperature were compared to industrial measurements as well as published models. The predictive quality of the hybrid model was superior to other models. This modeling approach can be used as an alternative to conventional modeling methods.

scholarly journals Electromagnetic steady motion of Casson fluid with heat and mass transfer through porous medium past a shrinking surface

2019 ◽  
pp. 416-416
Author(s):  
Nabil El-Dabe ◽  
Mohamed Abou-Zeid ◽  
Omar El-Kalaawy ◽  
Salah Moawad ◽  
Ola Ahmed
Keyword(s):  
Mass Transfer ◽  
Porous Medium ◽  
Differential Equations ◽  
Heat And Mass Transfer ◽  
Fluid Velocity ◽  
Steady Motion ◽  
Physical Parameters ◽  
Physical Situation ◽  
Fluid Temperature ◽  
Electric Parameter

The motion of non-Newtonian fluid with heat and mass transfer through porous medium past a shrinking plate is discussed. The fluid obeys Casion model, heat generation, viscous dissipation, thermal diffusion and chemical reaction are taken in our considered. The motion is modulated mathematically by a system of non liner partial differential equations which describe the continuity, momentum, heat and mass equations. These system of non linear equations are transformed into ordinary differential equations by using a suitable transformations. These equations are solved numerically by using Mathematica package. The numerical distributions of the velocity, temperature and concentration are obtained as a functions of the physical parameters of the problem. Moreover the effects of these parameters on these solutions are discussed numerically and illustrated graphically through some figures. It is clear that these parameters play an important role to control the velocity, temperature and concentration of the fluid motion. It?s found that the fluid velocity deceases with the increasing of electric parameter while it increases as the magnetic hartman parameter increases, these results is good agreement with the physical situation. Also, the fluid temperature decreases and increases as the Prandtl number and Eckert number increases respectively. At least the fluid concentration decreases with both of soret and schimdt numbers.

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