A global drift-fluid model is employed to study plasma discharges in linear devices including self-consistent treatment of electric fields. Numerical results on plasma rotation and turbulent scales are found to be very similar to experimental observations. Also a pronounced intermittent plasma transport in radial direction is observed for particular conditions. Extended filaments are expelled from the plasma column. In the simulations numerical probes have been implemented for detailed statistical analysis of the plasma fluctuations suitable for comparison with experimental data. In this contribution particular attention is paid to the impact of the plasma source on the intermittencies in the plasma column. It is found that even slight modifications in the shape of the plasma source can strongly change the plasma dynamics.