= New Rotor for Launchloop 2.1 =
This page is already obsolete. See VelocityTransformer for the new rotor design.
|| {{attachment:rotor05.png | | width=400 }} || The new rotor is composed of "block bolts", 5 millimeter square, perhaps 10 meter long blocks (or square bars) of laminated transformer steel, wrapped in thin aluminum wire hoop motor windings, and coated with amorphous diamond. The brown material around the deflector magnets represents copper coils, either providing the main deflection field (assumed around 2 Tesla) or the distance adjustment magnets opposite the deflection magnets.<
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>The bolts are spread sideways for travel around the high radial acceleration deflector magnets, bunched into a minimum cross section for passage up and down narrow tubes for passage through the windy and turbulent atmosphere, and reshaped into a V (or flat H) configuration to act as a velocity transformer rotor on the acceleration path.<
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>[[attachment:rotor05.png | png drawing for download]]||
|| {{attachment:Block_bolt3s.png | | width=400 }} || Illustration of a short segment of a block bolt - real bolt blocks will be much longer. Guesstimated dimensions will be 5 millimeters square, 10 meters long, 2 kilograms each. The gray sheets represent thin foil transformer steel, the copper colored hoops around the sheets represent aluminum-carbide-coated aluminum coils (they will be thin and flat in real life) and the transparent coating is amorphous diamond, like the material used to coat tools. . . . . [[ attachment:Block_bolt3s.png | png drawing for download ]] . . . .[[attachment:Block_bolt3.pov | Povray code for download ]] ||
Individual streams of bolts are "braided" and "un-braided" as they pass through the system. If there are 21 bolts in parallel as shown, they will follow a "mobius path" so they are positioned in each of the 21 positions consecutively.
All bolts are bar-coded, and the outer bolts are microscopically measured with laser-flash-illuminated ultra-high-speed cameras on every passage of each end; individual bolt streams will also be imaged on four sides, entering and exiting the D magnets and the turnarounds. Visibly damaged or misperforming bolts are swapped with fresh bolts launched from east return station and accelerated to rotor speed; the damaged bolts are ejected from west return station ... either slowed to fall into the ocean, or ejected at full rotor speed from west return station into Earth escape.
The east-to-west return track is used for bolt replacement. For speedup and swap operation, the new bolt is accelerated to full rotor speed over (WAG) 40% of the 2000 km return track (800 km), the bolts are deflected and swapped over 20% of the return track (400 km, or 32 seconds of swap time) and decelerate back to rest over the last 40% or 800 km. The bolts accelerate (using the transformer track mechanism at 10 gees, peak power approaching 2.5 megawatts, a small fraction of the 2000 MW of an eastward vehicle launch. There is an unsolved problem; as the bolt approaches rotor speed, the ''relative'' speed drops to zero, and the rate at which the rotor can deliver power does as well. Perhaps for this final surge, the stationary track can store energy (somehow), 200 joules per meter of capacitors, perhaps, extracted from the bolt being removed.
.'''Note''' It may also be practical to return launch sleds to west station with using the return track, but I would prefer to do that with fast cargo ships, less unnecessary risk to the system. Assume (WAG) that a sled costs $1M, and the investment interest rate is 18% per annum, and that we can move it 2000 km west at 40 km/h. Adding a day for handling at both ends, that is a 4 day return, and an interest cost of $2000 per cycle per sled. This also means that sleds can be integrated with launch vehicles, calibrated for release velocity, and tested for release speed/distance at the surface; less complication and time spent at west station, which probably saves more money than the added time in transit.
Assume a 12.5 km/s, 4.2 kg/meter rotor (bundles of 21) at 100 km altitude, with 5 centimeter end gaps between bolts at altitude. The kinetic energy per 2 kg bolt is 156.25 MJ. Descending to the surface adds about 1.92 MJ of gravitational energy, so the bolt energy becomes 158.17 MJ and the velocity increases to 12.577 km/s - 0.6% faster; since the mass flow rate remains the same, the density must decrease by 0.6%, hence the end gap spacing increases by 6 centimeters.
In the bundles, the 21 gaps are spread evenly between lines of bolts in the braid, so they occur every 50 centimeters or so, approximately a 26 kHz rate of gap passage, which is hopefully "fast and continuous enough" to be damped out by the inertia of the track and deflection magnets.
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