differential-producing primary device

differential-producing primary device

[dif·ə′ren·chəl prə‚düs·iŋ ¦prī‚mer·ē di′vīs]

(engineering)

An instrument that modifies the flow pattern of a fluid passing through a pipe, duct, or open channel, and thereby produces a difference in pressure between two points, which can then be measured to determine the rate of flow.