Patent ID: 8915136
Filing Date: 2014-12-23
Classification: G01B

Abstract:
1. A method of determining an internal cross-sectional area of a pipe along its length, the method including the steps of: (a) filling the pipe with a first fluid; (b) feeding a second fluid into the pipe at a known flow rate, the second fluid being immiscible with the first fluid, and a meniscus being formed at an interface between the first and the second fluid, the meniscus moving along the pipe as the second fluid displaces the first fluid in the pipe; (c) ultrasonically detecting a position of the meniscus as it moves along the pipe; and (d) determining from the second fluid flow rate and the meniscus position, the internal cross-sectional area of the pipe along its length, a volume V of the second fluid fed into the pipe being determined from the second fluid flow rate, and the internal cross-sectional area A of the pipe at a given meniscus position x being determined from the expression: A(x) =dV(x)/dx.