Patent ID: 7997149

Claim:
Apparatus for measuring the sound velocity of a fluid flowing in a tubing, comprising: an elongated cartridge having first and second ends to be placed between ends of the tubing, said cartridge having a hollow internal section formed by first and second chambers of different diameters communicating with said first and second ends and that define first and second walls that extend toward the cartridge longitudinal axis and are spaced apart by a known distance, wherein fluid is to flow into said first end, through said internal section and out through said second end; a piezoelectric sensor mounted in said hollow internal section to transmit signal energy to said first and second walls to be reflected back to said sensor; a circuit including a microprocessor to control the transmission of the signal energy by said sensor and for computing the round trip transit time of the signal energy transmitted by said sensor to each of said first and second walls and reflected therefrom back to said sensor; wherein said microprocessor is programmed with said known distance between said first and second walls and computes the sound velocity of the flowing fluid based on the difference of the two measured round trip transit times and the known fixed distance.