1. Department of Mechanical and Aerospace Engineering, Sapienza University of Rome , Via Eudossiana 18, Rome 00184, Italy
2. Institute for Fluid Mechanics, Friedrich-Alexander-Universität Erlangen-Nürnberg , Schloßplatz 4, Erlangen 91054, Germany
3. Institute for Fundamentals and Theory of Electrical Engineering, TU Graz , Rechbauerstraße 12, Graz 8010, Austria