The behavior of emitted charge cloud from an axisymmetric ion-flow anemometer

An ion-transit anemometer proposed previously was modified in order to make it easy to analyze its ion cloud behavior theoretically. The new probe used an axisymmetric ion emitter. With this probe different configurations of a detector ring were examined to estimate the size of the emitted charge cloud. By changing the diameter of the ring electrode, different detector signals were obtained. From these experiments, the size of the emitted charge cloud can be estimated. The velocity of the emitted ion cloud is between 2.0 and 2.2×10^-4 m²/Vs, which agrees with published data. Even if the charge cloud expands with distance from the emitter assembly, the velocity seems constant. The diameter of the charge cloud when it passes through the detector seems to be between 20 and 30 mm, depending on both V_B and V_p. Induction charge is much larger than emitted charge due to high voltage pulse