scholarly journals Modeling and analysis of the impact of exothermic catalytic chemical reaction and viscous dissipation on natural convection flow driven along a curved surface

2020 ◽  
Vol 24 (Suppl. 1) ◽  
pp. 1-11
Author(s):  
Uzma Ahmad ◽  
Muhammad Ashraf ◽  
Ilyas Khan ◽  
Kottakkaran Nisar
Keyword(s):  
Natural Convection ◽  
Viscous Dissipation ◽  
Chemical Reaction ◽  
Mass Concentration ◽  
Flow Model ◽  
Numerical Solutions ◽  
Convection Heat Transfer ◽  
Convection Flow ◽  
Catalytic Chemical Reaction ◽  
The Impact

The impact of exothermic catalytic chemical reaction and viscous dissipation on natural-convection heat transfer along the curved shape is investigated. In this study, the trend of exothermic catalytic chemical reaction has been introduced in the energy and mass concentration equation. Furthermore, the tangential compo?nent of acceleration due to gravity, gx, as buoyancy force has coupled in momentum equation describe the curved shape. The flow model of the problem is formulated in terms of coupled non-linear PDE together with suitable boundary conditions. From the numerical solutions of the governing equations, it is found that velocity field, temperature distribution and the mass concentration is associated with the dimensionless parameters involved in the flow model. The novelty of the current study is that the characteristics of heat and fluid-flow mechanism are specifically associated with the different values of index parameter n.

scholarly journals Modeling and analysis of the impact of exothermic catalytic chemical reaction and viscous dissipation on natural convection flow driven along a curved surface

2020 ◽  
Vol 24 (Suppl. 1) ◽  
pp. 1-11
Author(s):  
Uzma Ahmad ◽  
Muhammad Ashraf ◽  
Ilyas Khan ◽  
Kottakkaran Nisar
Keyword(s):  
Natural Convection ◽  
Viscous Dissipation ◽  
Chemical Reaction ◽  
Mass Concentration ◽  
Flow Model ◽  
Numerical Solutions ◽  
Convection Heat Transfer ◽  
Convection Flow ◽  
Catalytic Chemical Reaction ◽  
The Impact

The impact of exothermic catalytic chemical reaction and viscous dissipation on natural-convection heat transfer along the curved shape is investigated. In this study, the trend of exothermic catalytic chemical reaction has been introduced in the energy and mass concentration equation. Furthermore, the tangential compo?nent of acceleration due to gravity, gx, as buoyancy force has coupled in momentum equation describe the curved shape. The flow model of the problem is formulated in terms of coupled non-linear PDE together with suitable boundary conditions. From the numerical solutions of the governing equations, it is found that velocity field, temperature distribution and the mass concentration is associated with the dimensionless parameters involved in the flow model. The novelty of the current study is that the characteristics of heat and fluid-flow mechanism are specifically associated with the different values of index parameter n.

scholarly journals Effects of temperature dependent viscosity and thermal conductivity on natural convection flow along a curved surface in the presence of exothermic catalytic chemical reaction

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0252485
Author(s):  
Uzma Ahmad ◽  
Muhammad Ashraf ◽  
A. Al-Zubaidi ◽  
Aamir Ali ◽  
Salman Saleem
Keyword(s):  
Thermal Conductivity ◽  
Natural Convection ◽  
Velocity Profile ◽  
Chemical Reaction ◽  
Transfer Rate ◽  
Mass Concentration ◽  
Temperature Dependent ◽  
Temperature Dependent Viscosity ◽  
Dependent Viscosity ◽  
Catalytic Chemical Reaction

The natural convection boundary layer flow of a viscous incompressible fluid with temperature dependent viscosity and thermal conductivity in the presence of exothermic catalytic chemical reaction along a curved surface has been investigated. The governing non dimensional form of equations is solved numerically by using finite difference scheme. The numerical results of velocity profile, temperature distribution and mass concentration as well as for skin friction, heat transfer rate and mass transfer rate are presented graphically and in tabular form for various values of dimensionless parameters those are generated in flow model during dimensionalization. From the obtained results, it is concluded that the exothermic catalytic chemical reactions is associated with temperature dependent viscosity and thermal conductivity. Further, it is concluded that the body shape parameter also plays an important quantitative role for change in velocity profile, temperature field and mass concentration behavior in the presence of exothermic catalytic chemical reaction.

scholarly journals Mixed convection flow along a curved surface in the presence of exothermic catalytic chemical reaction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Uzma Ahmad ◽  
Muhammad Ashraf ◽  
Amir Abbas ◽  
A. M. Rashad ◽  
Hossam A. Nabwey
Keyword(s):  
Mixed Convection ◽  
Chemical Reaction ◽  
Mass Concentration ◽  
Body Shape ◽  
Shape Parameter ◽  
Curved Surface ◽  
Convection Flow ◽  
Mixed Convection Flow ◽  
Catalytic Chemical Reaction ◽  
Convection Parameter

AbstractIn the current study, the attention is paid on the phenomena of mixed convection flow under the effect of exothermic catalytic chemical reaction along the curved surface. The proposed problem is modeled in nonlinear coupled partial differential equations. In keeping view the principle of homogeneity the dimensional flow model is transformed into dimensionless by using an appropriate scaling. This well arranged form of equations is then discretized with the aid of finite difference method for the numerical solution. The solutions of the considered model are estimated and displayed in the graphs. Here, in the contemporary study variables of physical significance such as velocity profile, temperature distribution and mass concentration are encountered efficiently. The incorporated pertinent dimensionless numbers that is body shape parameter, mixed convection parameter, modified mixed convection parameter, Prandtle number, exothermic parameter, chemical reaction parameter, temperature relative parameter, dimensionless activation energy parameter, and Schmidt number for which variations in the concentrated physical variables are estimated and presented in graphical way. For each boundary conditions computations are performed along the curved surface for different body shape parameter (n) values range from 0 up to 0.5; the obtained results satisfied by the boundary conditions. The velocity profile becomes increasingly more significant for n equal to 1 and due to the uniformly heated surface temperature profile and mass concentration are uniformly distributed.

Entropy generation optimization for MHD natural convection of a nanofluid in porous media-filled enclosure with active parts and viscous dissipation

2017 ◽  
Vol 27 (2) ◽  
pp. 379-399 ◽  
Author(s):  
M.A. Mansour ◽  
Sameh Elsayed Ahmed ◽  
Ali J. Chamkha
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Viscous Dissipation ◽  
Entropy Generation ◽  
Local Heat Transfer ◽  
Local Heat ◽  
Convection Flow ◽  
Negative Effects ◽  
Content Type ◽  
Volume Method

Purpose This paper aims to investigate the entropy generation due to magnetohydrodynamic natural convection flow and heat transfer in a porous enclosure filled with Cu-water nanofluid in the presence of viscous dissipation effect. The left and right walls of the cavity are thermally insulated. There are heated and cold parts, and these are placed on the bottom and top wall, respectively, whereas the remaining parts are thermally insulated. Design/methodology/approach The finite volume method is used to solve the dimensionless partial differential equations governing the problem. A comparison with previously published woks is presented and is found to be in an excellent agreement. Findings The minimization of entropy generation and local heat transfer according to different values of the governing parameters are presented in details. It is found that the presence of magnetic field has negative effects on the local entropy generation because of heat transfer and the local total entropy generation. Also, the increase in the heated part length leads to a decrease in the local Nusselt number. Originality/value This problem is original, as it has not been considered previously.

scholarly journals Higher Order Accurate Transient Numerical Model to Evaluate the Natural Convection Heat Transfer in Flat Plate Solar Collector

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1508
Author(s):  
Nagesh Babu Balam ◽  
Tabish Alam ◽  
Akhilesh Gupta ◽  
Paolo Blecich
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Flat Plate ◽  
Solar Collector ◽  
Convection Heat Transfer ◽  
Air Gap ◽  
Convection Flow ◽  
Natural Convection Heat Transfer ◽  
Convection Heat ◽  
Flat Plate Solar Collector

The natural convection flow in the air gap between the absorber plate and glass cover of the flat plate solar collectors is predominantly evaluated based on the lumped capacitance method, which does not consider the spatial temperature gradients. With the recent advancements in the field of computational fluid dynamics, it became possible to study the natural convection heat transfer in the air gap of solar collectors with spatially resolved temperature gradients in the laminar regime. However, due to the relatively large temperature gradient in this air gap, the natural convection heat transfer lies in either the transitional regime or in the turbulent regime. This requires a very high grid density and a large convergence time for existing CFD methods. Higher order numerical methods are found to be effective for resolving turbulent flow phenomenon. Here we develop a non-dimensional transient numerical model for resolving the turbulent natural convection heat transfer in the air gap of a flat plate solar collector, which is fourth order accurate in both spatial and temporal domains. The developed model is validated against benchmark results available in the literature. An error of less than 5% is observed for the top heat loss coefficient parameter of the flat plate solar collector. Transient flow characteristics and various stages of natural convection flow development have been discussed. In addition, it was observed that the occurrence of flow mode transitions have a significant effect on the overall natural convection heat transfer.

Impact of Viscous Dissipation on Fully Developed Natural Convection Flow in a Vertical Microchannel

2018 ◽  
Vol 140 (9) ◽  
Author(s):  
Basant K. Jha ◽  
Babatunde Aina
Keyword(s):  
Natural Convection ◽  
Viscous Dissipation ◽  
Velocity Slip ◽  
Coupled System ◽  
Perturbation Series ◽  
Convection Flow ◽  
Natural Convection Flow ◽  
Flow Formation ◽  
Wall Interaction ◽  
Energy Equations

In this research paper, fully developed natural convection flow in a vertical parallel plate's micro-channel in the presence of viscous dissipation is theoretically examined by using a perturbation series method. The effects of velocity slip and temperature jump are taken to consideration. Due to the presence of viscous dissipation, the momentum and energy equations are coupled system of ordinary differential equations. The influences of Knudsen number, fluid wall interaction parameter, and viscous dissipation on the flow formation and heat transfer aspects are demonstrated through graphs and tables. This result indicates that increasing the value of rarefaction parameter decreases the effect of viscous dissipation on the Nusselt number. Furthermore, it is found that the effects of rarefaction parameter as well as buoyancy parameter on temperature and velocity are significantly pronounced in the case of symmetric heating

Sign in / Sign up

Export Citation Format

Share Document