A Model of Peaked Density Profile and Inward Pinch in Tokamaks

Sanae I. Itoh

Research output: Contribution to journalArticlepeer-review

22 Citations (Scopus)


A model theory of inward pinch and peaked density profile of ohmic discharges in the tokamak is presented. Ion anomalous viscosity in the presence of sheared rotation causes the drift across the magnetic field. Radial electric field, Er, can cause an inward pinch of electrons as well. The ratio of viscosities and the diffusion coefficient, the Prandtl number, determines the structures of Er and the density profile n(r) in a stationary state. In viscous plasmas, peaked profiles of both density and rotation velocity are expected. Reduction of edge neutrals changes the boundary condition and can induce further density peaking. Change of dEr/dr propagates into the center, causing ion viscous heating associated with the damping of velocity shear.

Original languageEnglish
Pages (from-to)3431-3434
Number of pages4
Journaljournal of the physical society of japan
Issue number10
Publication statusPublished - 1990
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)


Dive into the research topics of 'A Model of Peaked Density Profile and Inward Pinch in Tokamaks'. Together they form a unique fingerprint.

Cite this