Hydromagnetic Oscillatory Flow and Heat Transfer in Dusty Viscoelastic Fluid Through Porous Medium in an Inclined Channel in The Presence of Thermal Radiation and Heat Sink

In the present work, a compact modeling method based on a volume-averaging technique is presented. Its application to an analysis of fluid flow and heat transfer in straight fin heat sinks is then analyzed. In this study, the straight fin heat sink is modeled as a porous medium through which fluid flows. The volume-averaged momentum and energy equations for developing flow in these heat sinks are obtained using the local volume-averaging method. The permeability and the interstitial heat transfer coefficient required to solve these equations are determined analytically from forced convective flow between infinite parallel plates. To validate the compact model proposed in this paper, three aluminum straight fin heat sinks having a base size of 101.43mm×101.43mm are tested with an inlet velocity ranging from 0.5 m/s to 2 m/s. In the experimental investigation, the heat sink is heated uniformly at the bottom. The resulting pressure drop across the heat sink and the temperature distribution at its bottom are then measured and are compared with those obtained through the porous medium approach. Upon comparison, the porous medium approach is shown to accurately predict the pressure drop and heat transfer characteristics of straight fin heat sinks. In addition, evidence indicates that the entrance effect should be considered in the thermal design of heat sinks when Re Dh/L>∼O10.

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Thermal Optimization of Microchannel Heat Sink With Pin Fin Structures

Electronic and Photonic Packaging, Electrical Systems and Photonic Design, and Nanotechnology ◽

10.1115/imece2003-42180 ◽

2003 ◽

Cited By ~ 5

Author(s):

Duckjong Kim ◽

Sung Jin Kim

Keyword(s):

Heat Transfer ◽

Porous Medium ◽

Fluid Flow ◽

Heat Sink ◽

Volume Averaging ◽

Heat Sinks ◽

Pumping Power ◽

Heat Transfer Characteristics ◽

Pin Fin ◽

Flow And Heat Transfer

In the present work, a novel compact modeling method based on the volume-averaging technique and its application to the analysis of fluid flow and heat transfer in pin fin heat sinks are presented. The pin fin heat sink is modeled as a porous medium. The volume-averaged momentum and energy equations for fluid flow and heat transfer in pin fin heat sinks are obtained using the local volume-averaging method. The permeability, the Ergun constant and the interstitial heat transfer coefficient required to solve these equations are determined experimentally. To validate the compact model proposed in this paper, 20 aluminum pin fin heat sinks having a 101.43 mm × 101.43 mm base size are tested with an inlet velocity ranging from 1 m/s to 5 m/s. In the experimental investigation, the heat sink is heated uniformly at the bottom. Pressure drop and heat transfer characteristics of pin fin heat sinks obtained from the porous medium approach are compared with experimental results. Upon comparison, the porous medium approach is shown to predict accurately the pressure drop and heat transfer characteristics of pin fin heat sinks. Finally, surface porosities of the pin fin heat sink for which the thermal resistance of the heat sink is minimal are obtained under constraints on pumping power and heat sink size. The optimized pin fin heat sinks are shown to be superior to the optimized straight fin heat sinks in thermal performance by about 50% under the same constraints on pumping power and heat sink size.

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MHD mixed convection stagnation-point flow of a viscoelastic fluid towards a stretching sheet in a porous medium with heat generation and radiation

Canadian Journal of Physics ◽

10.1139/cjp-2013-0702 ◽

2015 ◽

Vol 93 (5) ◽

pp. 532-541 ◽

Cited By ~ 4

Author(s):

M. Modather M. Abdou ◽

E. Roshdy EL-Zahar ◽

Ali J. Chamkha

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Porous Medium ◽

Differential Equations ◽

Thermal Radiation ◽

Stagnation Point ◽

Viscoelastic Fluid ◽

Heat Generation ◽

Stretching Sheet ◽

Heat Transfer Characteristics

An analysis was carried out to study the effect of thermal radiation on magnetohydrodynamic boundary layer flow and heat transfer characteristics of a non-Newtonian viscoelastic fluid near the stagnation point of a vertical stretching sheet in a porous medium with internal heat generation–absorption. The flow is generated because of linear stretching of the sheet and influenced by the uniform magnetic field that is applied horizontally in the flow region. Using a similarity variable, the governing nonlinear partial differential equations have been transformed into a set of coupled nonlinear ordinary differential equations, which are solved numerically using an accurate implicit finite difference scheme. A comparison of the obtained results with previously published numerical results is done and the results are found to be in good agreement. The effects of the viscoelastic fluid parameter, magnetic field parameter, nonuniform heat source–sink, and the thermal radiation parameter on the heat transfer characteristics are presented graphically and discussed. The values of the skin friction coefficient and the local Nusselt number are tabulated for both cases of assisting and opposing flows.

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