Solar wind effect on the multi-fluid plasma expansion in the Venusian upper ionosphere

Inspired by the observations suggesting that at altitudes of about $1000$ km the interaction between solar wind streams and Venus' ionosphere plasma leads to ions acceleration and outflow, the influence of different solar wind physical parameters, such as densities, temperatures and initial streaming velocities, has been studied. The ionosphere plasma system consists of two positive ion populations $O^+$, $H^+$ and electrons along with the solar wind streaming protons and electrons. We calculated the generated oxygen and hydrogen ions flow velocities and the electric fields. In addition, we calculated rough estimates for the escaping flux of ion populations ($O^+$, $H^+$) from Venus' ionosphere and compared them to observations. To a large extent, we found that the estimates match. We also discuss the relevance of ionospheric ion acceleration and outflow from Venus' upper.