Patent ID: 9651442
Date: 2017-05-16
CPC Classifications: G01D,G01L,G01N

Claim:
1. A method of measuring the pressure of a contained fluid, the fluid being contained in a chamber which is defined, at least in part, by a first side wall, a second side wall, and an end wall each having an inner surface exposed to the fluid within the chamber, wherein the inner surface of the first side wall opposes the inner surface of the second side wall across the chamber, the end wall further having an outer surface separated from the inner surface of the end wall by the material of the end wall, the method comprising: providing the end wall to have inner and outer surfaces which are flat and parallel when the end wall is in a relaxed condition, wherein the inner surface of the end wall extends between the inner surface of the first side wall and the inner surface of the second side wall; introducing ultrasound into the material of the end wall at an introduction position; detecting the ultrasound after travelling through the material of the end wall to a detection position; measuring the time of flight of the detected ultrasound from the introduction position to the detection position; and providing a measurement of the fluid pressure at the inner surface of the end wall, as a function of the measured time of flight.