Thermogravitational convection of ferrofluid combined with the second law of thermodynamics for an open chamber with a heat-generating solid block under an influence of uniform magnetic field

2021 ◽  
Vol 129 ◽  
pp. 105712
Author(s):  
C. Sivaraj ◽  
E. Vignesh ◽  
M.A. Sheremet
Keyword(s):  
Magnetic Field ◽  
Uniform Magnetic Field ◽  
Second Law Of Thermodynamics ◽  
Second Law ◽  
Thermogravitational Convection ◽  
Solid Block

scholarly journals Realization of Maxwell’s Hypothesis: A Heat-Electric Conversion in Contradiction to the Kelvin Statement

2016 ◽  
Author(s):  
Xinyong Fu ◽  
Zitao Fu
Keyword(s):  
Magnetic Field ◽  
Uniform Magnetic Field ◽  
Room Temperature ◽  
Electric Energy ◽  
Second Law Of Thermodynamics ◽  
Ambient Air ◽  
The Other ◽  
Second Law ◽  
Heat Reservoir ◽  
Static Uniform Magnetic Field

In a vacuum tube, two identical and parallel Ag-O-Cs surfaces, with a work function of approximately 0.8eV, ceaselessly emit thermal electrons at room temperature. The thermal electrons are so controlled by a static uniform magnetic field that they can fly only from one Ag-O-Cs surface to the other, resulting in a potential difference and an electric current, and transferring a power to a resistance outside the tube. The ambient air is a single heat reservoir in the experiment, and all the heat extracted by the tube from the air is converted into electric energy without producing any other effect. The authors maintain that the experiment is in contradiction to the Kelvin statement of the second law of thermodynamics.

scholarly journals Realization of Maxwell’s Hypothesis: A Heat-Electric Conversion in Contradiction to the Kelvin Statement

2016 ◽  
Author(s):  
Xinyong Fu ◽  
Zitao Fu
Keyword(s):  
Magnetic Field ◽  
Uniform Magnetic Field ◽  
Room Temperature ◽  
Electric Energy ◽  
Second Law Of Thermodynamics ◽  
Ambient Air ◽  
The Other ◽  
Second Law ◽  
Heat Reservoir ◽  
Static Uniform Magnetic Field

In a vacuum tube, two identical and parallel Ag-O-Cs surfaces, with a work function of approximately 0.8eV, ceaselessly emit thermal electrons at room temperature. The thermal electrons are so controlled by a static uniform magnetic field that they can fly only from one Ag-O-Cs surface to the other, resulting in a potential difference and an electric current, and transferring a power to a resistance outside the tube. The ambient air is a single heat reservoir in the experiment, and all the heat extracted by the tube from the air is converted into electric energy without producing other effect. The authors maintain that the experiment is in contradiction to the Kelvin statement of the second law of thermodynamics.

Effect of Magnetic Field on the Laminar Heat Transfer Performance of Hybrid Nanofluid in a Lid Driven Cavity Over Solid Block

2020 ◽  
Author(s):  
Rajesh Nimmagadda ◽  
Durga Prakash Matta ◽  
Rony Reuven ◽  
Lazarus Godson Asirvatham ◽  
Somchai Wongwises ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Uniform Magnetic Field ◽  
Conjugate Heat Transfer ◽  
Heat Transfer Performance ◽  
Hybrid Nanofluid ◽  
Transfer Performance ◽  
Driven Cavity ◽  
The Magnetic Field ◽  
Solid Block

Abstract A 2D numerical investigation has been carried out to obtain the heat transfer performance of hybrid (Al2O3 + Ag) nanofluid in a lid driven cavity over solid block under the influence of uniform as well as non-uniform magnetic field. The geometrical domain consists of a cavity containing nanofluid that is driven by means of lid moving in one direction. This circulating nanofluid will extract enormous amount of heat from the solid block underneath the cavity resulting in conjugate heat transfer. A homogenous solver based on the finite volume method with conjugate heat transfer was developed and adopted in the existing study. The heat efficient hybrid nanofluid (HyNF) pair (2.4 vol.% Ag + 0.6 vol.% Al2O3) obtained by Nimmagadda and Venkatasubbaiah [1] is used in the present investigation. Moreover, efficient non-uniform sinusoidal magnetic field identified by Nimmagadda et al. [2] is also implemented and compared with uniform magnetic field. Furthermore, the magnetic field is applied over the geometrical domain along the two axial directions separately and the effective heat transfer performance is obtained. The significant impact of extensive parameters like Reynolds number, nanoparticle type, nanoparticle concentration, magnetic field type, magnetic field location and the strength of the magnetic field on heat transfer performance are systematically analyzed and presented.

scholarly journals Realization of Maxwell’s Hypothesis: A Heat-Electric Conversion in Contradiction to the Kelvin Statement

2016 ◽  
Author(s):  
Xinyong Fu ◽  
Zitao Fu
Keyword(s):  
Uniform Magnetic Field ◽  
Room Temperature ◽  
Electric Energy ◽  
Second Law Of Thermodynamics ◽  
Ambient Air ◽  
The Other ◽  
Second Law ◽  
Heat Reservoir ◽  
Measuring Process ◽  
Static Uniform Magnetic Field

In a vacuum tube, two identical and parallel Ag-O-Cs surfaces, with a work function of approximately 0.8eV, ceaselessly emit thermal electrons at room temperature. The thermal electrons are so controlled by a static uniform magnetic field that they can fly only from one Ag-O-Cs surface to the other, resulting in a potential difference and an electric current, and transferring a power to a resistance outside the tube. The ambient air is a single heat reservoir in the experiment, and all the heat extracted by the tube from the air is converted into electric energy without producing other effect. The authors maintain that the experiment is in contradiction to the Kelvin statement of the second law of thermodynamics. We have a video on you tube showing the main measuring process of the experiment: https://www.youtube.com/watch?v=PyrtC2nQ_UU.

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