ExB mean flows in finite ion temperature plasmas

TL;DR

This paper investigates how ion pressure fluctuations influence E x B mean flows in plasmas, revealing that additional stresses beyond Reynolds stress are crucial for understanding transport barriers.

Contribution

It introduces a simplified fluid model showing ion pressure fluctuations generate stresses that significantly affect E x B mean flows, a novel insight for plasma transport analysis.

Findings

Ion pressure fluctuations contribute additional stresses to E x B flows.

These stresses are as important as Reynolds stress in plasma dynamics.

Inclusion of these stresses is essential for modeling transport barriers.

Abstract

The impact of ion pressure dynamics on E x B mean flows is investigated. Using a simplified, two-dimensional, drift ordered fluid model in the thin-layer approximation, three stresses in addition to the Reynolds stress are shown to modify the E x B mean flow. These additional terms in the stress tensor all require ion pressure fluctuations. Quasi-linear analysis show that these additional stresses are as important as the Reynolds stress, and hence must be taken into account in analysis of transport barriers in which sheared E x B mean flows are key ingredients.