Patent ID: 6587798
Filing Date: 2003-07-01
Classification: G01N,G01V

Abstract:
A method for measuring the speed of sound c in a fluid contained within an elongated body, the sound traversing the elongated body substantially along a direction aligned with the longest axis of the elongated body, the sound causing a momentary change in pressure in a portion of the fluid as the sound traverses the portion of the fluid, the method comprising the steps of:a) providing at predetermined locations an array of at least two sensors distributed along the elongated body, each sensor for discerning and signaling spatio-temporally sampled data including information indicating the pressure of the fluid at the position of the sensor; b) acquiring the spatio-temporally sampled data from each sensor at each of a number of instants of time; c) constructing a plot derivable from a k&ohgr; plot, using a technique selected from the group consisting of spectral-based algorithms, such as the Capon method or the MUSIC method, in which a spectrum-like function of the speed of sound is formed, and parametric methods of solution, such as the deterministic maximum likelihood method; d) identifying in the k&ohgr; plot a spectral ridge, and determining the slope of the spectral ridge; and e) determining the speed of sound assuming a relation between the speed of sound and the slope of the spectral ridge.