We have generated an empirically based scaling relation for the thermal diffusivity, sχ⊥, in the scrape-off layers (SOL) of tokamaks using a database of global energy confinement time versus core plasma parameters from 110 ohmically heated tokamak discharges whose core plasma parameters, viz., Te, ne, B, curvature, radial scale length, and Zeff, are similar to the values expected in the SOL of tokamaks like ITER. These data were interpreted with an all-possible-regressions model/multiple-regressions analysis to obtain the best fit for τE versus ne, Te, R, a, Zeff and V. A cylindrical-shell thermal transport model was used to extract sχ⊥ from τE. Reasons for ignoring the effects on sχ⊥ of sheath phenomena and parallel transport on open field lines are discussed.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Materials Science(all)
- Nuclear Energy and Engineering