Corona wheel

    The first one was the study of a mobile corona (tourniquet experiment).

Tourniquet experiment

    The starting speed was fixed by the adjustment of the high voltage and the intensity was simultaneously measured with voltage so the electrical power was known. Then we suddenly cut the electrical power and measured the speed decay.

Speed decay

     The resulting deceleration with the known inertia momentum permitted the calculus of the force and then the mechanic power. The maximum speed was around 20 m/s and we were able to show that the force remained constant up to that speed. In order to investigate higher speeds we decided to blow on the mobile part with compressed air. Then we measured the speed decay with and without the discharge.

Speed decay with air blowing

    With this artefact it was possible to show that the force remains constant up to speeds higher than 50 m/s, and that the efficiency can reach values higher than 15 %.

Force and Efficiency

    This work was published in the J.A.P (Journal of Applied Physics) in the years 83-84.