Vortices generate fluid oscillations that are detected when they pass through the beam and induce {TAIL ~ phase changes} representative of {HEAD ~ fluid flow rate} 
Vortices generate fluid oscillations that are detected when they pass through the beam and induce { TAIL ~ phase changes } representative of { HEAD ~ fluid flow rate }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD