Figure 4
Toroidal RIE and measuring setup: (a) Toroidal RIE mounted on the measuring device; negative high voltage is fed from the shaft above the toroidal ground collector; (b) setup used for measuring the airflow speed and estimation of the volume flow rate; an anemometer with a rotating vane and a plastic adaptor for focusing flow are used as shown; (c) details of the ionic system mounted on the thrust measuring seesaw device (d) 4-RIE array mounted on the seesaw measuring device; at the opposite end there is a balancing weight and an electronic scale measuring the overall axial ionic thrust.
