Patent ID: 8695435
Filing Date: 2014-04-15
Classification: G01F

Abstract:
1. A method of determining a volume flow rate of a controlled media in a pipeline (CMP), comprising the steps of: (a) forming a sequence of primary ultrasound signals (USS); (b) alternately transmitting the USS in and counter the direction of a flow of the CMP; (c) alternately receiving the USS that passed in and counter the direction of the flow of the CMP; (d) forming a mutual correlation function of the codes of the USS passed in the direction of the flow of the CMP and the codes of the primary USS, to thereby determine the time of USS transmission in the direction of the flow of the CMP; (e) forming a mutual correlation function of the codes of the USS passed counter the direction of the flow of the CMP and the codes of the primary USS, to thereby determine the time of USS transmission counter the direction of the flow of the CMP; (f) forming a mutual correlation function of the codes of the USS passed in and counter the direction of the flow of the CMP, to thereby determine the difference between the time of USS transmission in and counter the direction of the flow of the CMP; (g) forming a code of the position address for the maximum value of the mutual correlation function of the codes of the USS passed in and counter the direction of the flow of the CMP, to thereby form a code of the time difference of the USS transmission in and counter the direction of the flow of the CMP; (h) forming an array of address codes corresponding to moments of zero crossing of the codes of the USS passed in the direction of the flow of the CMP; (i) determining the code of zero crossing moment address for the codes of the USS passed in the direction of the flow of the CMP, which the closest to the code of the position address for the maximum value of the mutual correlation function; (j) selecting a part of codes of the USS passed in the direction of the flow of the CMP, which corresponds to the maximum value of the correlation function; (k) forming a mutual correlation function of the selected part of the codes of the USS passed in the direction of the flow of the CMP and a delayed code phase shifted by 90° in relation to codes of the primary USS; (l) re-digitizing this mutual correlation function at mf (m) selecting a part of codes of the USS passed counter the direction of the flow of the CMP, which corresponds to the maximum value of the correlation function; (n) forming a mutual correlation function of the selected part of the codes of the USS passed counter the direction of the flow of the CMP and a delayed code phase shifted by 90° in relation to codes of the primary USS; (o) re-digitizing this mutual correlation function at in f (p) determining a code of the accurate difference of time intervals between the USS passed in and counter the direction of the flow of the CMP according to the formula ΔT=ΔT (q) determining the volume flow rate of the CMP from the formula where: ΔT—the code of accurate difference of time of USS transmission in and counter the direction of the flow of the CMP; T 1 —the code of time of USS transmission in the direction of the flow of the CMP; T 2 —the code of time of USS transmission counter the direction of the flow of the CMP; τ—the constant value that depends on the dimension geometry and materials of the transmitting-receiving radiators of USS; and κ—a proportionality factor depending on the geometric dimensions inside the pipeline.