Fig.10 shows the variation of the ion concentration of the io and collector outlets with ion flow rate. At higher ion flow rates, the ion number concentration was high. The magnitude of the ion number concentration at the io outlet was much larger than at the ion collector outlet. It was expected that ions partially would be lost by electrostatic deposition inside the ion collector due to Brownian diffusion, electrostatic dispersion (space charge) and an external electric field. With ion concen-trations above 10
13ions/m3, ions may partially deposit onto the inner and outer electrodes of the ion collector by space charge effects in the absence of any applied voltage on the inner elec-trode. As shown inFig. 10, the ion number concentration at the ionizer outlet had a range from 9.3810 11 to 1.911013ions/m3, and 2.261012 to 1.791013ions/m3 for positive and negative corona voltages, respectively.