Model C stellarator
{{Short description|American nuclear fusion reactor}}
{{Infobox fusion devices
|name = Model C stellarator
|fullname =
|image =
|imagetitle =
|type = Stellarator
|city = Princeton
|state = New Jersey
|country = United States
|affiliation = Princeton Plasma Physics Laboratory
|major_radius =
|minor_radius = {{cvt|5|-|7.5|cm}}
|volume =
|field = {{cvt|3.5|T}}
|heating =
|power =
|time =
|current =
|temperature =
|construction_date = 1961
|operation_start_year = 1962
|operation_end_year = 1969
|prev = Model A/B stellarators
|next = Symmetric Tokamak (ST)
|related =
|website =
|other_links =
}}
The Model C stellarator was the first large-scale stellarator to be built, during the early stages of fusion power research. Planned since 1952, construction began in 1961 at what is today the Princeton Plasma Physics Laboratory (PPPL).{{Cite journal|last=Stix|first=T. H.|date=1998|title=Highlights in early stellarator research at Princeton|url=http://www.jspf.or.jp/JPFRS/PDF/Vol1/jpfrs1998_01-003.pdf|journal=J. Plasma Fusion Res.|volume=1|pages=3–8|language=English}} The Model C followed the table-top sized Model A, and a series of Model B machines that refined the stellarator concept and provided the basis for the Model C, which intended to reach break-even conditions. Model C ultimately failed to reach this goal, producing electron temperatures of 400 eV when about 100,000 were needed. In 1969, after UK researchers confirmed that the USSR's T-3 tokamak was reaching 1000 eV, the Model C was converted to the Symmetrical Tokamak, and stellarator development at PPPL ended.
Design parameters
The Model C had a racetrack shape. The total circumference of the magnetic axis was 12 m.{{Cite journal |last=Yoshikawa |first=S. |last2=Stix |first2=T.H. |date=1985-09-01 |title=Experiments on the Model C stellarator |url=https://iopscience.iop.org/article/10.1088/0029-5515/25/9/047 |journal=Nuclear Fusion |volume=25 |issue=9 |pages=1275–1279 |doi=10.1088/0029-5515/25/9/047 |issn=0029-5515}} The plasma could have a 5-7.5 cm minor radius. Magnetic coils could produce a toroidal field (along the tube) of 35,000 Gauss. It was only capable of pulsed operation.
It had a divertor in one of the straight sections. In the other it could inject 4 MW of 25 MHz ion cyclotron resonance heating (ICRH).
It had helical windings on the curved sections.
Results
An average ion temperature of 400 eV was reached in 1969.
History
Construction funding/approval was announced in April 1957 with the design based on Katherine Weimer's efforts in fundamental research.[https://books.google.com/books?id=LxJbAAAAYAAJ&dq=model+c+stellarator&pg=RA10-PA9 Princeton Alumni Weekly, Volume 57. April 19. p9]{{Cite journal|last1=Johnson|first1=John L.|last2=Greene|first2=John M.|date=September 2000|title=Katherine Ella Mounce Weimer|journal=Physics Today|volume=53|issue=9|pages=88|doi=10.1063/1.1325250|issn=0031-9228|doi-access=free}}
It started operating March 1962.[http://www.pppl.gov/about/history/timeline See 1962]
The Model C was reconfigured as a tokamak in 1969, becoming the Symmetric Tokamak (ST).[http://www.pppl.gov/about/history/timeline See 1969,1970]
References
{{reflist}}
Further reading
- [http://iopscience.iop.org/article/10.1088/0029-5515/25/9/047/pdf Experiments on the Model C stellarator. S. Yoshikawa and T.H. Stix ]
- [http://www.osti.gov/scitech/biblio/4299735 A CONCEPTUAL DESIGN OF THE MODEL C STELLARATOR. 1956] Says 9" vacuum tube, but 150 ft long seems unlikely. 150,000 kW peak of pulsed power to the magnets.
{{Fusion power}}