The accelerated positively charged ions accelerate {HEAD ~ low energy air} within {TAIL ~ lower regions} of a boundary layer over the ducted surfaces bounding the ducted fluid flow 
The accelerated positively charged ions accelerate { HEAD ~ low energy air } within { TAIL ~ lower regions } of a boundary layer over the ducted surfaces bounding the ducted fluid flow
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH