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# Homopolar induction

## http://encyclopedia2.thefreedictionary.com/Homopolar+Induction

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased. Homopolar Induction

(in Russian, unipoliarnaia induk-tsiia), the generation of an electromotive force (emf) in a magnetized body moving in a direction that is not parallel to the axis of magnetization. The direction of the emf is perpendicular to the plane in which the magnetic induction vector B and the magnet’s velocity vector v lie.

If the magnetized body is a conductor, homopolar induction may be explained in the framework of classical electrodynamics. Under the action of the Lorentz force, free electrons drift within the body in a direction perpendicular to the directions of v and B until an electric field that impedes the drift is generated in the body.

The theory of relativity provides a consistent explanation of homopolar induction. In the reference frame associated with the magnet, or the proper frame of reference, there is no electric field E. Suppose the magnet moves with a velocity v in the laboratory reference frame and the motion is uniform, translational, and rectilinear. Then, according to the relativistic field-strength equations, the electric field E in the laboratory frame is E = – [vB]/c, where c is the speed of light; the value of E is accurate to within the factor Homopolar Induction, which is practically equal to 1 for small values of v. The equation for the electric field is applicable both within and outside the magnetized body, regardless of whether the body is a conductor. Thus, homopolar induction is a relativistic effect in which the relative nature of the partition of an electromagnetic field into an electric field and a magnetic field is explicitly revealed.

The presence of an electric field gives rise to a constant potential difference. This phenomenon is used to generate a direct current in homopolar generators.

The term “unipolar induction,” of which the Russian term is a cognate, is deprecated in English. The term came into use because, in a homopolar generator, all the magnetic poles presented to the circuit in which the emf is induced are of the same polarity. REFERENCE Tamm, I. E. Osnovy teorii elektrichestva, 8th ed. Moscow, 1966.

## 1.5 million ampere Balcones Homopolar Pulse Generator for rail gun tests

Six-gang Drum-homopolar pulse generators built at the University of Texas at Austin - Center for Electromechanics for extremely high current generation.
Source: http://www.utexas.edu/research/cem/facilities.html
"The Center’s laboratory facility was built in 1985 as an energy storage and pulsed-power prototype test facility. To support this effort, The University of Texas funded the manufacture and installation of the Balcones Homopolar Generator Power Supply (BHPG). The 60 MJ BHPG power supply includes six 10 MJ homopolar generators and six 2-turn coaxial inductors, along with a high current, high voltage bus turret to enable flexible series/parallel interconnection. The generators are installed in a hexagonal pit in the high bay with the central bus and inductors mounted at floor level. Each drum-type homopolar generator is capable of producing output pulses of 1.5 MegaAmpere peak current at approximately 100 V dc. Using the coaxial inductors and explosive opening and closing switches, output pulses at voltages of >10 kV with peak currents of up to 3 MegaAmperes have been delivered to railgun loads. Timed staging of the switches can be used to tailor the characteristics of the output pulse."

### A primer on the Homopolar Phenomenon

by Luc Lachapelle
Source: http://www.icestuff.com/~energy21/hoprima.htm
Although a tremendous quantity of effort has been invested toward research on the Homopolar phenomenon, still today after more than 180 years following its identification by Faraday, very little information has been made public and its usage has not yet found its way into our daily lives.
Its awkward since it is known in the scientific community that the Homopolar electric generation is naturally Extra-Efficient. The single engineering challenge has been all along the conception of a working unit which does not cripple the generation process while tapping this freely given energy.
The goal of the present document is to bring some insight on the working principles of various contractions which by definition are employing the Homopolar phenomenon. I hope it will be of service to all.

## U.S. Patents

Dynamo Electric Machine (homopolar)
406968
Nichola Tesla, 1889
Source: FreePatentsOnline.com http://www.freepatentsonline.com/0406968.pdf

Homopolar Generator
U. S. Patent 6,051,905
William F. Weldon, 1996
"An electrical homopolar capacitor generator includes a set of stacked dielectric plates and conductive plates arranged in a magnetic field, with at least one ol the dielectric plates is rotated relative to the remainder of the plates to generate an electrical output charge between the conductive plates. One version of the generator employs flat circular disks with an inner dielectric disk rotated relative to the others. The inner disk is placed between a pair of electrically conductive plates, which in turn are placed between a pair of first and second dielectric plates which are in a fixed relationship to the conductive plates. A second embodiment utilizes concentric cylinders in a similar arrangement to the stacked circular disk embodiment, with relative rotation of an inner dielectric being effected along a common axis for all of the cylindrical plates."

Homopolar Machine (traditional with improved brushes)
U. S. Patent 5530309
"An improved homopolar machine in which a solid sliding current collector, or brush, is provided for contact with a flat, annular contact surface of a rotor. The flat plane of the contact surface is orthogonal to the rotor's axis of rotation. A plurality of such contact surfaces with corresponding...

List of homopolar generator patents Wikipedia.org

### More by Luc L.

http://www.linux-host.org/energy/kirlian.htm
http://www.icestuff.com/~energy21/homopolar.htm

# in edit

## brought from Esoterical References

This section is an early drapht.
University of Texas at Austin, The Center for Electromechanics
Homopolar Pulse Welding of Martensitic Stainless Steel Linepipe (PN 248) - Y. Ichiyama*, H. Asahi*, R.S. Hudson, R.W. Carnes, and R. Hebner, Third International Conference on Pipeline Technology Conference, Brugge, Belgium, May 22-24, 2000
Department of Physics, University of Maryland
• Homopolar Motor Demo: Simple homopolar motor using a screw, a battery, a neodymium magnet and a piece of wire (Wikipedia.com)
• Homopolar Motor Demo: Simple homopolar motor made with a AA battery, one neodymium magnet, and short piece of bare copper wire (dangerouslyfun.com).
Richard E. Berg and Carroll O. Alley, Department of Physics, University of Maryland, College Park, MD 20742 (Edited January, 2005)
by Bruce E. DePalma,
RexResearch.com, 11 October 1985

(c)1996 William J. Beaty

• DePalma home page: Bruce DePalma and his N-Machine and homopolar generator research

The Center’s laboratory facility was built in 1985 as an energy storage and pulsed-power prototype test facility. To support this effort, The University of Texas funded the manufacture and installation of the Balcones Homopolar Generator Power Supply (BHPG). The 60 MJ BHPG power supply includes six 10 MJ homopolar generators and six 2-turn coaxial inductors, along with a high current, high voltage bus turret to enable flexible series/parallel interconnection. The generators are installed in a hexagonal pit in the high bay with the central bus and inductors mounted at floor level. Each drum-type homopolar generator is capable of producing output pulses of 1.5 MA peak current at approximately 100 V dc. Using the coaxial inductors and explosive opening and closing switches, output pulses at voltages of >10 kV with peak currents of up to 3 MA have been delivered to railgun loads. Timed staging of the switches can be used to tailor the characteristics of the output pulse.

• London Effect: an Esoterica References Article on spinning superconductor tests found to warp gravity

## Meissner Motor Demonstration

### Argonne National Laboratory

Richard McDaniel demonstrates the Meissner motor
Announced by Argonne on Dec. 30, 1987. The small, popular demonstration device was the world's first motor based on the unique properties of high-temperature superconductors.
Source
ANL Science and Technology

### Naval Research Contract on Full-scale Superconducting DC Homopolar Motor for Ship Propulsion

Saturday, 11 March 2006
GENERAL ATOMICS TO DESIGN AND FABRICATE ADVANCED PROPULSION MOTOR FOR US NAVY
Anonymous. NATO's Nations and Partners for Peace. Uithoorn 2005., Iss. 1, pg. 150, 1 pgs
ISSN/ISBN 15669009
Abstract
The Office of Naval Research has awarded General Atomics (GA) a \$46-million contract for detail design, fabrication, and factory testing of a full-scale superconducting dc homopolar motor for ship propulsion. Under this contract, GA will deliver a 36.5-megawatt, 120rpm advanced design prototype motor, motor drive, and support equipment, which will be shipped to a US Navy facility for full-performance testing. This full-scale system is sised [[sic] to propel large vessels, such as destroyers, now in development by the Navy.
Source: ProQuest database