In this particular study, we have considered the flow of Casson fluid over inclined flat and cylindrical surfaces, and have conducted a numerical analysis taking into account various physical factors such as mixed convection, stagnation point flow, MHD, thermal radiation, viscous dissipation, heat generation, Joule heating effect, variable thermal conductivity and chemical reaction. Flow over flat plate phenomena is observed aerospace industry, and airflow over solar panels, etc. Cylindrical surfaces are commonly used in several applications interacting with fluids, such as bridges, cables, and buildings, so the study of fluid flow over cylindrical surfaces is more important. Due to the motivation of these applications, in this paper, a comparative study of fluid flow over these two surfaces is considered. By applying appropriate similarity transformations, the governing PDEs of the problem have been transformed into non-linear ODEs, which are solved by utilizing the Keller box technique. We have examined the impact of distinct parameters by plotting velocity and thermal concentration graphs. All the profiles are plotted in both cases of cylindrical and inclined flat surface. It has been observed that for higher Casson and Magnetic parameter values, a decreasing velocity profile is noted for progressive values of the Eckert Number, thermal conductivity parameter, Joule heating parameter, heat generation, and growth in temperature profiles are witnessed. While the Prandtl number shows the opposite trend. Further, it has been observed that the concentration profile declines for incremental observations of Schmidt number and chemical reaction parameters. Computed Local parameters like the coefficient of skin friction for various values of Casson parameter and Curvature parameter, Skin friction value increases for increasing observations of Curvature parameter the phenomena agree with existing literature. Also, Nusselt number is calculated for various observations of curvature and variable thermal conductivity parameters. Nusselt number decreases in magnitude with rising observations of varying thermal conductivity argument at both flat and cylindrical surfaces. The values are matched with prevailing results and noted a good agreement.

The widespread occurrence of non-Newtonian fluid behaviour in various applications, including natural and technological ones. After introducing the concept of non-Newtonian fluids, a brief overview of their distinct features is mentioned [

As heat transfer involves transferring and converting energy, it is important to define the specified level of heat exchange at a specified temperature modification. It is imperative for some components, such as turbine blades, electrical machines, electronic gadgets, transformers, bearings, etc, to remove thermal energy at a quick rate to prevent overheating. Therefore, it is essential to understand how heat transfers and the governing laws of heat transfer. By mass transfer, we mean the transfer of matter based on a concentration difference between species in a system. It has several applications in the fields of science, engineering and technology. As a result of its importance in a wide variety of industrial and scientific applications, stagnation point flow continues to be an interesting area of research for scientists and investigators. Stagnation flow is useful for designing thrust bearings and radial diffusers, reducing drag, and cooling by transpiration. Radiation is the heat transfer process that happens using electromagnetic waves. The transmission of heat by radiation comprises the drift of heat energy from the origin to the space surrounded by it. The movement of energy can be carried out by using electromagnetic waves. Energy is transferred by thermal radiation in combustion chambers, furnaces, and nuclear explosions. The Joule heating effect is the process of creating heat when a current passes through an electrical conductor. Joule heating is used in many heating devices, such as electric stoves, electric heaters, soldering irons, cartridge heaters, and food processing equipment. Flow over flat plate phenomena is observed aerospace industry, and airflow over solar panels, etc. Cylindrical surfaces are commonly used in several applications interacting with fluids, such as bridges, cables, buildings, so the study of fluid flow over cylindrical surface has a greater importance.

Due to the motivation of these applications, In this paper, a comparative study of Casson fluid flow over these two surfaces is taken into consideration. In the present study, Casson fluid’s two-dimensional stagnation point flow is analyzed on both flat and cylindrical surfaces with the influences of radiation, mixed convection, MHD, heat source, Joule heating, viscous dissipation and chemical reaction. Here a magnetic field is applied externally to fluid flow. The governing equations are explained by Keller Box numerical technique.

We considered the two-dimensional Casson fluid stream, Inclined at an angle α at both flat and cylindric surfaces. Here u and v are components of velocity towards the r-axis and x-axis Flow over surface is affected by MHD, Chemical reaction, viscous dissipation, radiation, Joule heating, variable thermal conductivity and mixed convection. The geometry of the problem is mentioned in

Based on these suppositions, the leading partial differential equations [

In this case, the boundary conditions are as follows:

Corresponding similarity transformations [

By utilizing the similarity transforms, the governing

and the converted boundary conditions

Using,

Using the concept of finite differences, convert the equations to difference equations and linearize them using Newton’s method.

The system of linear equations are

where,

Further, the resultant system of linear equations is solved using Block tri-diagonal elimination technique and solved using LU decomposition method.

The matrix form of equations [

To validate the method, the current outcomes are matched with old literature.

The influence of distinct parameters is analyzed by plotting graphs for both cases of a flat plate (G = 0), Cylindrical surface (G = 0.4) with MATLAB.

Here for all the graphs, we considered curvature parameter G = 0.0 for flat plate and G = 0.4 for cylindrical surfaces.

The measure of skin friction rises as the curvature argument increases and decreases with the Casson parameter’s progressive values. This phenomenon agrees with the previous study mentioned in

Hayat et al. [ |
Islam et al. [ |
Present study | ||
---|---|---|---|---|

1.0 | 0.1 | 1.2347 | 1.2135 | 1.2241 |

1.5 | 0.1 | 1.1082 | 1.1030 | 1.1045 |

2.0 | 0.1 | 1.0310 | 1.0150 | 1.0322 |

2.0 | 0.0 | 0.9966 | 0.9643 | 0.9620 |

2.0 | 0.1 | 1.0409 | 1.0214 | 1.0414 |

2.0 | 0.2 | 1.0850 | 1.0413 | 1.1079 |

Hayat et al. [ |
Islam et al. [ |
Present study | |||
---|---|---|---|---|---|

2.0 | 0.19 | 0.0 | 0.5739 | 0.5216 | 0.5273 |

2.0 | 0.19 | 0.2 | 0.5308 | 0.5124 | 0.5167 |

2.0 | 0.19 | 0.3 | 0.5123 | 0.5061 | 0.5116 |

2.0 | 0.0 | 0.0 | 0.5442 | 0.5220 | 0.5718 |

2.0 | 0.12 | 0.0 | 0.5336 | 0.5213 | 0.5287 |

2.0 | 0.19 | 0.0 | 0.5279 | 0.5016 | 0.5052 |

In this paper, a two-dimensional Casson fluid flow at both inclined flat and cylindrical surfaces, a comparative study of heat and mass transfer characteristics in a Casson immobility point flow is investigated. Flow is influenced by MHD, thermal radiation, Joule heating, variable thermal conductivity, mixed convection, viscous dissipation and chemical reaction. The corresponding equations are resolved by employing Keller Box method. Numerical calculations are analyzed, and the following observations are noted:

A decrement in velocity graphs was witnessed for progressive estimates of Casson, Magnetic parameters and the reverse trend is observed for higher observations of velocity ratio parameter.

Increment in temperature graphs witnessed for incremental estimates of the Eckert number, Joule heating, thermal conductivity parameter, and heat generating parameter. The opposite trend is noted for the Prandtl number.

Concentration graphs decline for the Schmidt number, Chemical reaction.

The magnitude of friction drag rises as the curvature argument increases.

Nusselt number reduces in magnitude with enhanced observations of changeable thermal conductivity parameter.

In the present investigation, a comparative study is carried out between two surfaces flat and cylindrical, by considering Casson fluid flow and this work can be expanded for other non-Newtonian fluids.

Cylindric coordinates

Components of velocity

Angle of inclination

Casson argument

Kinematic viscosity coefficient (

Acceleration due to gravity (

Solutal expansion coefficient

Thermal expansion coefficient (per °

Magnetic constraint

Prandtl number

Schmidt number

Free stream temperature

Fluid temperature

_{0}

Magnetic field constant

Fluid Concentration (mol/m^{3})

Free stream concentration

Free stream velocity

Electrical conductivity (s/m)

Specific heat (J/Kg.K)

Heat flux (W/m^{2})

Thermal conductivity (W/mk)

Chemical reaction parameter

Variable thermal conductivity parameter

Velocity ratio parameter

Thermal radiation parameter

Concentration Grashof number

Thermal Grashof number

Mass diffusivity parameter

Eckert number

Curvature parameter

Chemical reaction parameter

The authors are thankful to Koneru Lakshmaiah Education Foundation for providing research facilities to carry out this study.

The authors received no specific funding for this study.

Sridhar Wuriti: Supervision, Conceptualization, Validation, Software; Shaik Jafarullah: Writing–original draft, Methodology, Data curation, Visualization, Project administration; Raghavendra Ganesh Ganugapai: Visualization, Writing review & editing; Srinivasa Rao Talagadadevi: Conceptualization, Data curation.

Data will be made available on request.

The authors declare that they have no conflicts of interest to report regarding the present study.

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