Image Credits and References:
R.G. Harrison, “The Global Atmospheric Electrical Circuit and Climate,” http://arxiv.org/ftp/physics/papers/0506/0506077.pdf
The task is to design and build several rotating machines that operate on stored electric charge, rather than magnetic fields. The two motor styles to be investigated are a corona motor and an electret motor. The corona motor operates at high voltage and turns at high speed due to a rapid charge-exchange process carried on St. Elmo’s fire. The electret motor uses a special homemade dielectric slab that retains a permanent charge without an external voltage source (like a permanent magnet). By configuring the electret between two DC rotor plates, the machine spins in a manner similar to a brushed DC motor and is called a slot-effect electret motor. Initially, both motors will be tested in the laboratory using a high-voltage power supply. The refined motors will be taken to the field and powered from the electricity present in the atmosphere. A balloon-borne antenna will capture power produced by thunderstorms underway around the earth.
Level of Difficulty: Medium
stator, rotor, armature, corona, electret, electric field intensity, electric flux density, permittivity, resistivity, Cockcroft-Walton generator, whirl instability
Oleg Jefimenko, Electrostatic Motors; http://www.rexresearch.com/jefimenko/jefimenko.htm
D. Moore, ed., Electrostatics and its Applications, John Wiley and Sons, NY, 1973, ISBN 0-471-61450-5
Jefimenko, “Operation of Electric Motors from the Atmospheric Electric Field,” Am. J. Phys., 39, p.776-778 (1971)
Electrical Engineer (2) – Electrical Engineers on the project are responsible for the design and construction of a high-voltage, low-current power supply. The device provides continuously adjustable voltages from 0 to 12 kV at a maximum current of 10 mA. Furthermore, the supply will be equipped with safety interlocks and store a minimal amount of energy. Additional safety features will include a system that rapidly removes any stored energy and disables the output when the supply is turned off.
Mechanical Engineer (2) – The Mechanical Engineers are responsible for the rotating elements of the two motor styles. The corona motor operates with high voltage and turns at a very high speed. Special considerations include low-friction bearing and careful balancing to avoid instabilities. The slot-effect electret motor turns at a low speed but also needs low-friction bearings and a dust-free enclosure. Both motors require precise engineering and accurate manufacturing.
Geophysicist (2) – Geophysicists on the project are responsible for the design and construction of a high altitude antenna system that delivers high-voltage atmospheric power to the motors. The balloon lifting body will support one or more sharpened antenna and be restrained by a lightweight tether combined with a very thin copper wire. The balloon anchor is connected to the ground and supports both motor styles on an insulated platform. The system uses a hand-operated wench to deploy and retrieve the balloon.
Chemist (2) – The Chemists are responsible for the production of several electret disks that will become the heart of the slot-effect motors. The Chemists mix various wax portions into a mold and electrify the melted mixture for the prescribed time. Additionally, the potential of the electrets will be measured so that the accumulated field reversal on the disks can be plotted over time.
Designer (2) – Designers have the difficult task of integrating the antenna, motor, and laboratory power systems together. Furthermore, the integrated design must be portable and able to be safely demonstrated to groups indoors or outside in the field.
Journalist (1) – The Journalist documents the project’s progress on the website, communicates with the local media, and is responsible for a final report. The Journalist also works closely with the Multimedia Artist to provide video and graphic art displays for demonstrations that explain the project to the public. The whole project is your project.
Multimedia Artist (1) – The Artist also documents the project’s progress on the website and works with the Journalist to maintain the project’s presence on social media. Additionally, the Artist designs and organizes all public relations events to assure spectator safety and to enhance the community’s awareness of science and technology. The whole project is your project.
Business Manager (1) – The Business Manager is responsible for reporting the project’s progress against a predetermined schedule, determines critical path items to completion, and tracks project spending to assure that costs remain within a fixed budget. The Manager works with all team members to identify problems early and resolve them quickly. The whole project is your project.