Unsteady squeezed flow of radiated rheological fluid in a channel with activation energy

This study explores the effectiveness of periodically placed rotating blades in enhancing heat transfer in a channel. The channel consists of a cold top plate moving at a constant speed and a fixed hot plate at the bottom. Thin rotating blades are placed periodically along the channel's centerline, with the spacing between their axes equal to the channel's height. This paper analyzes a transient, two‐dimensional, laminar flow problem using energy, momentum, and continuity equations. To address the challenges posed by moving blades, the Galerkin finite element method is implemented within an arbitrary Lagrangian–Eulerian framework, employing a triangular mesh discretization scheme. This study comprehensively explores thermal and hydrodynamic characteristics, including overall heat transfer, thermal frequency, and power consumption of the rotating blade for heat transfer in mixed convection scenarios with Richardson numbers (Ri) ranging from 0.1 to 10 at varying rotational frequency of the blade. Outcomes demonstrate that the inclusion of a rotating blade increases heat transfer up to 50% at lower Ri, after which the impact of the rotating blade diminishes and heat transfer reduces up to 20% at higher Ri. In addition, heat transfer enhances with increasing blade frequency up to Ri = 6.5, beyond which the effect of the frequency overturns. Examining thermal and hydrodynamic characteristics reveals that the blade achieves optimal performance when operating at f = 1 and Ri = 3. The study's insights into mixed convection heat transfer offer versatile applications, benefiting industries and equipment such as electronic cooling, chemical reactors, food processing, material fabrication, solar collectors, and nuclear reactor systems. Moreover, the findings are instrumental in the thermal ventilation of buildings and the development of micro‐electromechanical systems.

Section: Study On Heat Transfer Enhancement Employing Flow Modulatorsmentioning

confidence: 99%

Mixed convection characteristics in a long horizontal lid‐driven channel with periodically distributed local flow modulators

Nahin,

Qaum,

Chowdhury

et al. 2024

“…Last but not least, Hussain and Ahmed 25 added to the conversation by exploring how a magnetic field controls the motion along a stretched surface implanted in a material of pores in a fluid type of micropolar, furthering our understanding of this complex field of study. The unsteady MHD flow of Casson fluid through a porous channel has been investigated by Gangadhar et al 26 The influence of bioconvection on the flow behavior of Williamson nanofluid over a stretching cylinder was numerically investigated by Gangadhar et al 27 The time dependent flow of Powell Eyring nanofluid over a vertical stretching sheet with entropy minimization was analyzed by Gangadhar et al, 28 they reported that the rise in the Brinkman number and Reynolds number enhances the entropy of the system.…”

Section: Introductionmentioning

confidence: 99%

COMSOL Multiphysics simulation of hydromagnetic flow in horizontal channels with diverse media: Insights into momentum and heat diffusion limitations

Ahmed,

Das

2024

The Darcy–Forchheimer model for a two‐dimensional hydromagnetic flow in a horizontal channel, including the dynamic interaction of porous and nonporous media, is investigated in this study due to the importance of the consequences of heat exchange in porous materials. The novelty of the current investigation is to study the hydrodynamics of fluid flowing through a channel with free and non‐Darcy porous media linked next to one another influenced by the potent Lorentz force. The prime objective of this investigation is to analyze the influence of critical nondimensional parameters on the rate of heat transfer and shear forces exerted on the walls of the channel. Numerical simulations are carried out using the finite element method within the COMSOL Multiphysics program, which offers a versatile framework to explore the behavior of velocity and isothermal contours. The essential optimal stability of this adopted model is achieved for specific scenarios employing a finely meshed grid and grid‐independent analysis. It is noteworthy that larger Prandtl numbers enhance heat transmission rates from surfaces at high temperatures, whereas greater Eckert numbers are correlated with lower Nusselt numbers. On the lower surface, the Forchheimer and magnetic drag forces reduce skin friction, whereas the top surface displays a different pattern. The aforesaid findings have a variety of engineering applications by improving the flow dynamics in porous and nonporous materials. This study can be beneficial in designing heat exchanger devices.

“…Using MATLAB's Runge-Kutta method for effective problem-solving, the novelty is in incorporating variable parameters, like viscosity and wall thickness, to understand their effects on fluid dynamics and temperature. The study Gangadhar et al 34 examines the effects of activation energy on the two-dimensional unsteady squeezing flow of Casson fluid with radiation in a porous channel. Through the numerical solution of nonlinear differential equations using a finite difference scheme, the study sheds light on the relationship between flow characteristics and magnetic field strength.…”

Section: Introductionmentioning

confidence: 99%

Analytical solution to boundary layer flow and convective heat transfer for low Prandtl number fluids under the magnetic field effect over a flat plate

Agrawal,

Gupta

2024

The present study aims to quantify the flow field, flow velocity, and heat transfer features over a horizontal flat plate under the influence of an applied magnetic field, with a particular emphasis on low Prandtl number fluids. Nonlinear partial differential expressions can be incorporated into the ordinary differential framework with the use of appropriate transformations. This research utilizes the variational iteration method (VIM) to approximate solutions for the system of nonlinear differential equations that define the problem. The objective is to demonstrate superior flexibility and broader application of the VIM in addressing heat transfer issues, compared to alternative approaches. The results obtained from the VIM are compared with numerical solutions, revealing a significant level of accuracy in the approximation. The numerical findings strongly suggest that the VIM is effective in providing precise numerical solutions for nonlinear differential equations. The analysis includes an examination of the flow field, velocity, and temperature distribution across various parameters. The study found that improving temperature patterns, velocity distribution, and flow dynamics were all positively impacted by increasing the Prandtl numbers. As a result, this leads to the thickness of the boundary layer to decrease and improves heat transfer at the moving surface. Thus, the convection process becomes more efficient. When the strength of the magnetic field is increased, the velocity of the fluid decreases. This observation aligns with expectations since the magnetic field hampers the natural flow of convection. Notably, the convection process can be precisely controlled by carefully applying magnetic force.