Authors: Zhaoming Gan (New Mexico Consortium), Hui Li (Los Alamos National Laboratory), Xiangrong Fu (Los Alamos National Laboratory), Senbei Du (Boston University) and Lingling Zhao (4University of Alabama in Huntsville)

We perform high-resolution global 3D compressible MHD simulations on the turbulent solar winds by injecting various waves/perturbations at the corona base, aiming to simulate the turbulence development in the Near-Sun environments, including understanding the evolution of nonlinear fluctuations in the expanding winds, especially the origin of density fluctuations. Unlike sub-grid turbulence models, our numerical resolution is high enough to resolve the “break frequency” and part of the “inertial range”, which enables us to study the nonlinear activities of individual waves and energy dissipation within the limited dynamical range. The wave injection, thus the wind acceleration and fluctuation levels, is calibrated with observations. Virtual satellites are implemented during the simulations to make plasma samples at runtime, which makes it possible to compare our results directly with in-situ measurements. Special attention is paid to the parametric decaying instability and its roles in developing turbulence and the density fluctuations as observed by the Parker Solar Probe.