[Table of Contents]

Plasma and Fusion Research

Volume 9, 1302137 (2014)

Letters


A Statistical Approach for Predicting Thermal Diffusivity Profiles in Fusion Plasmas as a Transport Model
Masayuki YOKOYAMA
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 18 July 2014 / Accepted 11 August 2014 / Published 31 October 2014)

Abstract

A statistical approach is proposed to predict thermal diffusivity profiles as a transport “model” in fusion plasmas. It can provide regression expressions for the ion and electron heat diffusivities (χi and χe), separately, to construct their radial profiles. An approach that this letter is proposing outstrips the conventional scaling laws for the global confinement time (τE) since it also deals with profiles (temperature, density, heating depositions etc.). This approach has become possible with the analysis database accumulated by the extensive application of the integrated transport analysis suite to experiment data. In this letter, TASK3D-a [M. Yokoyama et al., Plasma Fusion Res. 9, 3402017 (2014)] analysis database for high-ion-temperature (high-Ti) plasmas [H. Takahashi et al., Nucl. Fusion 53, 073034 (2013)] in the LHD (Large Helical Device) [O. Kaneko et al., Nucl. Fusion 53, 104015 (2013)] is used as an example to describe an approach.


Keywords

multiple ordinary least squares (OLS) regression analysis, TASK3D-a, LHD analysis database, energy transport

DOI: 10.1585/pfr.9.1302137


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This paper may be cited as follows:

Masayuki YOKOYAMA, Plasma Fusion Res. 9, 1302137 (2014).