On the potential distribution resulting from flow across a magnetic field projecting from a plane wall

1968 ◽  
Vol 33 (1) ◽  
pp. 73-86 ◽  
Author(s):  
Roger C. Baker
Keyword(s):  
Magnetic Field ◽  
Velocity Field ◽  
Electric Potential ◽  
Potential Field ◽  
Potential Distribution ◽  
Velocity Profiles ◽  
Plane Wall ◽  
Slow Variation ◽  
Electric Potential Field

When a fluid of low conductivity flows parallel to a plane wall from behind which projects a magnetic field, an electric potential field is established throughout the fluid. In this paper the potential field is obtained explicitly in terms of the velocity field when the latter is unidirectional and depends only on the coordinate normal to the wall. Experiments with a variety of velocity profiles are described, and the agreement with the theory is satisfactory. The effect of slow variation of the profiles in the direction of the flow is considered, and is shown to be unimportant under the conditions of the experiments.

scholarly journals Sunspot Magnetic Fields and High Energy Electrons in Flares

1971 ◽  
Vol 43 ◽  
pp. 390-396
Author(s):  
Tatsuo Takakura
Keyword(s):  
Magnetic Fields ◽  
Electric Potential ◽  
Potential Field ◽  
Large Scale ◽  
Plasma Waves ◽  
High Energy ◽  
Ohmic Loss ◽  
X Ray ◽  
High Energy Electrons ◽  
Electric Potential Field

A balloon observation of an impulsive hard X-ray burst on September 27, 1969 showed the size of the source to be one arc minute or less. It was remarkably smaller than the associated Hα flare with a size of 3 arc min.The efficient acceleration of electrons and the trigger of the flares are suggested to be attributed to a large scale electric potential field caused by a gas motion near the photosphere. The primary cause of the onset of flares would be the acceleration of electrons. The electrons excite plasma waves which make the conductivity lower by several orders, so that the electromagnetic energy I2L stored before the onset of the flare would be suddenly converted into the heat due to the ohmic loss.

scholarly journals Study on Electroosmosis Consolidation of Punctiform Electrode Unit

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Xiaoyu Yang ◽  
Yongbin Xie ◽  
Jianhua Dong ◽  
Guosheng Liu ◽  
Yalin Zheng
Keyword(s):  
Finite Element ◽  
Pore Water ◽  
Potential Field ◽  
Potential Distribution ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Two Dimensional ◽  
Dimensional Model ◽  
One Dimensional ◽  
Electric Potential Field

In the electroosmosis method, when the distance between the opposite electrode and the same electrode is equal, the two-dimensional effect of electroosmotic consolidation is significant, and the use of one-dimensional model will overestimate the potential gradient, making the calculated pore pressure value too large. Aiming at this problem, according to the electrode arrangement rule and the minimum composition, a punctiform electrode unit model is proposed, and electroosmotic experiments are carried out on the symmetric and asymmetric unit models. The two-dimensional electroosmotic consolidation governing equation of the punctiform electrode unit is established. The electric potential field of the electrode unit and the finite element form of the electroosmotic consolidation equation are given by the Galerkin method. The PyEcFem finite-element numerical library is developed using Python programming to calculate. The research results show the following: (1) The two-dimensional effect of the potential field distribution of the punctiform electrode unit is significant. The reduction of spacing of the same nature electrode in the symmetrical unit can make the potential distribution close to a uniform electric field. The asymmetry prevents the electric potential field distribution from being reduced to a one-dimensional model. (2) The number of anodes will affect the electroosmosis effect of the soil. The more the anodes, the better the electroosmosis reinforcement effect of the soil, and the distribution of negative excess pore water pressure will be more uniform. (3) In the early stage of electroosmosis, the more the drainage boundaries, the faster the generation of negative pore pressure, but in the middle and late stages of electroosmosis, the potential value becomes the decisive factor, and the amplitude of negative pore water pressure in asymmetric units is higher than that in symmetric units. The potential distribution will not affect the degree of consolidation but will affect the extreme pore water pressure.

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