The ionic wind occurs with corona discharge. Knowledge of the ionic wind in a machine is necessary as a measure of the degradation of the image that originates from the generation products on corona discharge. The authors investigate the characteristics of the ionic wind in the neighborhood of a double-wire corona device through computational fluid dynamics to better understand this phenomenon. Various flow characteristics have been found. An inflow appears at the upper ventilation slit in the fan-off case. The primary flow diverges into some branches in a cross section. The authors can easily comprehend that this primary flow is derived from the schematic distribution of the body force. Several secondary vortices are induced by this flow at the same time. It is necessary to consider the effect of the grid electrode. Our numerical calculations correlate well with our experimental results by Particle Image Velocimetry. The primary flow appears also in a cross section on push-pull ventilation. Static pressure decreases along the wire. Large circulation occurs on the upstream side. Free powders that should contaminate the corona device move on the circulation. Large circulation thus has a close relation to contamination.