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

Abstract

The ion-transit anemometer which had been proposed previously was modified for the ease to analyze its ion cloud behavior theoretically. The new probe used an axisymmetric ion emitter. With this symmetrical configuration of ion emitter assembly, the motion of emitted ion cloud becomes axisymmetnc. With this probe the different configuration of a detector r h g was examined to estimate the size of emitted charge cloud. By changing the diameter of a ring electrode, the different detector signals were obtained. From these experiments, the size of emitted charge cloud can be estimated. Although the emitted charge cloud expands with proceeding, the diameter of charge cloud at the detector position seems to be 20 -30 mm. The average velocity of charge cloud between electrodes seems fairly constant even if expanding. The measured ion-mobility agrees well with the reported value.

Corona Discharge Velocimeter

“…Later work on the ionic anemometers was carried out by several authors [5,6,18,19,20,23,31,40,41] in order to design probes for specific applications. However all these ionic devices are dedicated to the measure of the fluid flow velocity : they estimate average velocity and fluctuations associated with turbulence.…”