US4548782A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tokamak plasma heating with intense, pulsed ion beams
Assignee: United States Department of the Navy
•
Filing: 1980-03-27
•
Granted: 1985-10-22
•
Expires: 2000-03-27
Abstract
Abstract An intense, space-charge-neutralized, pulsed ion beam is used to heat a magnetically-confined plasma, such as tokamak plasma, by injecting the ion beam into the plasma along a trajectory that is generally tangential to the confining magnetic field. The intense ion beam is injected into the tokamak before the plasma is fully formed, the remainder of the plasma is formed around the beam, and the beam transfers its energy to the plasma by classical collisions with the electrons and ions of the plasma. Heating of the plasma can be sufficient to produce breakeven or ignition.
Inventors
- 👤 Wallace M. Manheimer
- 👤 Niels K. Winsor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:41
CPC Classifications
G; G21; G21B; G21B1/00; G21B1/11; G21B1/23; Y; Y02; Y02E; Y02E30/00; Y02E30/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
84 words
Apparatus for heating a plasma, the plasma being confined in an apparatus of the type wherein the plasma is confined in a vacuum chamber by a magnetic field, comprising: means for producing a space-charge-neutralized, pulsed, ion beam; means for directing the ion beam into the magnetic field before the plasma is fully formed; and means for forming the remainder of the plasma around the beam, the beam transferring its energy to the plasma by classical collisions with the electrons and ions of the plasma.
Claim 2
Dependent Claim
84 words
Apparatus for heating a plasma, the plasma being confined in an apparatus of the type wherein the plasma is confined in a vacuum chamber by a magnetic field, comprising: means for producing a space-charge-neutralized, pulsed, ion beam; means for directing the ion beam into the magnetic field before the plasma is fully formed; and means for forming the remainder of the plasma around the beam, the beam transferring its energy to the plasma by classical collisions with the electrons and ions of the plasma.
Claim 3
Dependent Claim
30 words
The apparatus recited in claim 1, wherein the ion beam is directed into the magnetic field along a trajectory generally tangential to the lines of force of the magnetic field.
Claim 4
Dependent Claim
66 words
The apparatus recited in claim 1, wherein a vacuum region is formed surrounding the plasma; and the ion frequency of the beam is very much larger than the square of the gyrofrequency of the beam in the magnetic field, thereby producing a polarization electric field in the beam when it enters the magnetic field, the polarization field enabling the beam to propagate across the vacuum region.
Claim 5
Dependent Claim
25 words
The apparatus recited in claim 1 wherein the plasma-forming means includes: fast pulsed valve means for injecting a puff of gas into the vacuum chamber.
Claim 6
Independent Claim
70 words
A method for heating a plasma confined in a magnetic field in a vacuum chamber comprising the steps of: (a) producing a space-charge-neutralized pulsed ion beam; (b) injecting the beam into the magnetic field before the plasma is fully formed; and (c) forming the remainder of the plasma around the beam, the beam transferring its energy to the plasma by classical collisions with the electrons and ions of the plasma.
Claim 7
Independent Claim
70 words
A method for heating a plasma confined in a magnetic field in a vacuum chamber comprising the steps of: (a) producing a space-charge-neutralized pulsed ion beam; (b) injecting the beam into the magnetic field before the plasma is fully formed; and (c) forming the remainder of the plasma around the beam, the beam transferring its energy to the plasma by classical collisions with the electrons and ions of the plasma.
Claim 8
Dependent Claim
31 words
The method recited in claim 5 wherein step (b) includes: directing the beam into the magnetic field along a trajectory generally parallel to the lines of force of the magnetic field.
Claim 9
Dependent Claim
19 words
The method recited in claim 5 wherein step (c) includes: injecting a puff of gas into the vacuum chamber.
Claim 10
Dependent Claim
37 words
The method recited in claim 5 including the step of: (d) inactivating external means for driving a current in the plasma subsequent to step (c) so that the entire plasma current is carried by the ion beam.
References Cited (Backward Citations)
GB848346A
Cited
US3047480A
Cited
US3749639A
Cited
US3831101A
Cited
US4057462A
Cited
US4065351A
Cited
US4115191A
Cited
US4172008A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-21 | 1989-04-22 | 1989-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-21 | 1993-04-22 | 1993-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-21 | 1997-04-22 | 1997-10-22 | $7700.00 | Window Closed / Lapsed |