Tandem Mirror

A more advanced mirror approach involving multicells, called the tandem mirror, has been studied as a means to overcome the leakage problem. One way to view the tandem mirror is as a long uniform magnetic solenoid with two single-cell mirrors installed at the ends to electrostatically plug the device. Plasma end losses ate impeded by electrostatic potentials developed by the plasma as the electrons and ions attempt to leave the device at different rates. 

The next sections describe three reactor studies with emphasis on the lithium-structure compatibility. HYLIFE is a liquid metal wall (LMW) ICF reactor considered here for electricity production. It has also been adapted to fissile fuel production ( 5). The Tandem Mirror Reactor (TMR) Cauldron Blanket Module is an MCF concept designed to produce hydrogen. The TMR Heat Pipe Blanket Module is designed to produce either hydrogen or electricity. All three studies emphasize materials compatibility with lithium. Tritium recovery techniques and two aspects of lead-lithium liquids are also discussed. 

Design Concept. Thermochemical cycles for hydrogen production lend themselves well to use of a Tandem Mirror Reactor (TMR) heat source with a liquid Li blanket design. This linkage of a thermochemical hydrogen cycle to a TMR is favorable for several reasons ( )... 

Werner, R. W "The Fusion-Synfuel Tie Producing Hydrogen With the Tandem Mirror Reactor" presented at 15th Intersociety Energy Conversion Engineering Conference Seattle, WA, 1980. 

Krikorian, 0. H. "Materials Considerations for the Coupling of Thermochemical Hydrogen Cycles to Tandem Mirror Reactors" Proc. 4th ANS Top. Mtg. Tech. Controlled Nucl. Fusion King of Prussia, PA, 1980. 

The use of high M simple mirrors at the ends of a high density, theta-pinch-like column does not appear useful because of the instability of such devices. However, the use of sophisticated doublemirror electrostatic traps, which forms the basis for the tandem mirror program, is very promising. This approach, which developed from the "Q-enhancement program" for simple mirrors, has historically not been considered as a "long linear system," and is discussed elsewhere in this workshop. 

Once the beam is parallel, a set of two steering mirrors are used in tandem to position the beam at a height that matches the center of the top cube containing the dichroic beamsplitter. The mirrors should be mounted at 45° angles on mirror mounts with adjustable pitch and should be placed so that the first mirror reflects the excitation beam perpendicular to the table and the second reflects the beam parallel to the table, with the beam incident at... 

Fig. 2 Typical Brillouin scattering setup using a tandem of triple-passed Fabry-Perot interferometers. M mirrors, SF spatial filters. FP Fabry Perot interferometers, c corner cubes. IF interferential filter, 1-12 half-wave plate. PM photomultipliers, P pinholes. A Gian analyzer. S fast shutter. G glass plate, and PC personal computer for data acquisition. (From Ref [13].) (View this art in color at WWW. dekker. com.)...

Scanning the etalon and coarse tuner in tandem, the laser will tune in steps of the cavity FSR, c/21c, where Ic is the cavity length. Typical cavity FSRs are on the order of 300 MHz. Tuning the laser frequency between adjacent cavity modes can be achieved by smoothly increasing the cavity length by X/2. This is usually accomplished with a piezoelectric transducer (PZT)-driven cavity mirror or a tilted Brewster angle plate. To achieve smooth continuous scans, the three tuning elements must be synchronized. 

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