contrapropagating ultrasonic flowmeter

contrapropagating ultrasonic flowmeter

[¦kän·trə′prä·pə‚gād·iŋ ′əl·trə‚sän·ik ′flō‚mēd·ər]
(engineering)
An instrument for determining the velocity of a fluid flow from the difference between the times required for high-frequency sound to travel between two transducers in opposite directions along a path having a component parallel to the flow.