Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 13
Book Description
New Fluctuation Phenomena in the H-mode Regime of PDX Tokamak Plasmas
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 13
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 13
Book Description
Energy Research Abstracts
Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 662
Book Description
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 662
Book Description
Energy Research Abstracts
Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 692
Book Description
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 692
Book Description
Observation of Finite-. Beta. MHD Phenomena in Tokamaks
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Stable high-beta plasmas are required for the tokamak to attain an economical fusion reactor. Recently, intense neutral beam heating experiments in tokamaks have shown new effects on plasma stability and confinement associated with high beta plasmas. The observed spectrum of MHD fluctuations at high beta is clearly dominated by the n = 1 mode when the q = 1 surface is in the plasma. The m/n = 1/1 mode drives other n = 1 modes through toroidal coupling and n> 1 modes through nonlinear coupling. On PDX, with near perpendicular injection, a resonant interaction between the n = 1 internal kink and the trapped fast ions results in loss of beam particles and heating power. Key parameters in the theory are the value of q0 and the injection angle. High frequency broadband magnetic fluctuations have been observed on ISX-B and D-III and a correlation with the deterioration of plasma confinement was reported. During enhanced confinement (H-mode) discharges in divertor plasmas, two new edge instabilities were observed, both localized radially near the separatrix. By assembling results from the different tokamak experiments, it is found that the simple theoretical ideal MHD beta limit has not been exceeded. Whether this represents an ultimate tokamak limit or if beta optimized configurations (Dee- or bean-shaped plasmas) can exceed this limit and perhaps enter a second regime of stability remains to be clarified.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Stable high-beta plasmas are required for the tokamak to attain an economical fusion reactor. Recently, intense neutral beam heating experiments in tokamaks have shown new effects on plasma stability and confinement associated with high beta plasmas. The observed spectrum of MHD fluctuations at high beta is clearly dominated by the n = 1 mode when the q = 1 surface is in the plasma. The m/n = 1/1 mode drives other n = 1 modes through toroidal coupling and n> 1 modes through nonlinear coupling. On PDX, with near perpendicular injection, a resonant interaction between the n = 1 internal kink and the trapped fast ions results in loss of beam particles and heating power. Key parameters in the theory are the value of q0 and the injection angle. High frequency broadband magnetic fluctuations have been observed on ISX-B and D-III and a correlation with the deterioration of plasma confinement was reported. During enhanced confinement (H-mode) discharges in divertor plasmas, two new edge instabilities were observed, both localized radially near the separatrix. By assembling results from the different tokamak experiments, it is found that the simple theoretical ideal MHD beta limit has not been exceeded. Whether this represents an ultimate tokamak limit or if beta optimized configurations (Dee- or bean-shaped plasmas) can exceed this limit and perhaps enter a second regime of stability remains to be clarified.
Fusion Energy Update
Author:
Publisher:
ISBN:
Category : Controlled fusion
Languages : en
Pages : 134
Book Description
Publisher:
ISBN:
Category : Controlled fusion
Languages : en
Pages : 134
Book Description
INIS Atomindex
Author:
Publisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 1526
Book Description
Publisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 1526
Book Description
H-modes Studies in PDX.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A regime of enhanced energy confinement during neutral beam heating has been obtained routinely in the PDX tokamak after modifications to form a closed divertor geometry. Plasma density profiles were broad and the electron temperature at the plasma edge reached values of approx. 400 eV in the H-mode phase of a discharge. A comparison of closed divertor discharges with moderate and intense gas puffing indicates that a requirement for obtaining high confinement times is the localization of the plasma fueling source in the divertor throat region. While high confinement was attained at moderate injected powers (P/sub INJ/ less than or equal to 3 MW), confinement was degraded at higher powers due to both increased edge instabilities and, especially, the intense gas puffing needed to prevent disruptions. Initial results with a particle scoop limiter indicate high particle confinement times and energy confinement times approaching those of diverted H-mode plasmas.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A regime of enhanced energy confinement during neutral beam heating has been obtained routinely in the PDX tokamak after modifications to form a closed divertor geometry. Plasma density profiles were broad and the electron temperature at the plasma edge reached values of approx. 400 eV in the H-mode phase of a discharge. A comparison of closed divertor discharges with moderate and intense gas puffing indicates that a requirement for obtaining high confinement times is the localization of the plasma fueling source in the divertor throat region. While high confinement was attained at moderate injected powers (P/sub INJ/ less than or equal to 3 MW), confinement was degraded at higher powers due to both increased edge instabilities and, especially, the intense gas puffing needed to prevent disruptions. Initial results with a particle scoop limiter indicate high particle confinement times and energy confinement times approaching those of diverted H-mode plasmas.
Government reports annual index
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 1082
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 1082
Book Description
Physics Briefs
Author:
Publisher:
ISBN:
Category : Physics
Languages : en
Pages : 862
Book Description
Publisher:
ISBN:
Category : Physics
Languages : en
Pages : 862
Book Description
Government Reports Annual Index: Keyword A-L
Author:
Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 1000
Book Description
Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 1000
Book Description