# Impact of micro-scale stochastic Zonal Flows on the macro-scale V-RMHD modes

## TL;DR

This paper presents a stochastic model of micro-scale Zonal Flows and investigates their stabilizing effects on macro-scale MHD modes, revealing potential turbulence-driven stabilization mechanisms.

## Contribution

Introduces a stochastic modeling approach for micro-scale ZFs and examines their impact on stabilizing MHD modes, a novel insight into turbulence effects on plasma stability.

## Key findings

- Stochastic ZFs can significantly stabilize (2,1) and (1,1) MHD modes.
- Both passive and semi-stochastic models show stabilization effects.
- Micro-scale turbulence influences macro-scale plasma stability.

## Abstract

A model is developed to simulate micro-scale turbulence driven ZFs, and their impact on the MHD tearing and kink modes is examined. The model is based on a stochastic representation of the micro-scale ZFs with a given Alfv\'{e}n Mach number, M_S. Two approaches were explored: i) passive stochastic model where the ZFs amplitudes are independent of the MHD mode amplitude, and ii) the semi-stochastic model where the amplitudes of the ZFs have a dependence on the amplitude of the MHD mode itself. The results show that the stochastic ZFs can significantly stabilise the (2,1) and (1,1) MHD modes even at very low kinematic viscosity, Pr, where the mode is linearly unstable. Our results, therefore indicate a possible mechanism for stabilisation of the MHD modes via small-scale perturbations in poloidal flow, simulating the turbulence driven ZFs.