Ultrasonic Flow Meter Time Difference Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for measuring the volume flow rate of a controlled medium in a pipeline are inaccurate due to insufficient precision in calculating the difference in time of ultrasonic signal transmission in and counter to the flow direction, leading to errors in computing the volume flow rate.
Innovation Solution
The method involves forming mutual correlation functions to determine the time difference of ultrasonic signal transmission in and counter to the flow direction, using a succession of steps including forming primary ultrasonic signals, transmitting and receiving signals, computing mutual correlation functions, and calculating the volume flow rate using the accurate difference in time intervals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional time difference calculation methods are used, then the device complexity is low, but the measurement precision of volume flow rate deteriorates
Solution Approach 1:
The patent applies preliminary action by forming mutual correlation functions between transmitted and received ultrasonic signals before performing time difference calculation. This preprocessing step prepares the signals in advance to enable more accurate time interval measurement between signal transmissions in opposite directions, thereby improving volume flow rate measurement precision.
Solution Approach 2:
The patent replaces traditional direct time difference calculation methods with a signal processing approach using mutual correlation functions. This substitution transforms the measurement problem from direct temporal comparison to frequency-domain signal analysis, enabling more precise determination of time intervals between ultrasonic signal transmissions.
2Measurement precision
If direct time difference calculation is used, then the calculation process is simple, but the accuracy of time interval measurement deteriorates
Solution Approach 1:
The patent forms mutual correlation functions as a preliminary processing step before time difference calculation. This advance preparation of signal relationships enables more accurate extraction of time interval information by establishing the correlation between transmitted and received signals in advance.
Solution Approach 2:
The patent transforms the measurement approach by changing from direct time comparison to correlation-based time interval extraction. By forming mutual correlation functions, the method converts temporal measurement into a function-based analysis, improving measurement accuracy through parameter transformation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly enhances the accuracy of volume flow rate measurement by precisely calculating the time difference, resulting in a more reliable computation of the volume flow rate.
Implementation Method 1
providing ultrasound signals (USS), alternately radiating USS into synchronized rings
Implementation Method 2
measuring the time of propagation along and counter the flow
Data Source
AI summary
Method comprises transmitting and receiving ultrasound signals (USS) in and counter direction of flow (ICDF) of controlled medium in pipeline (CMP); determining times of USS transmission ICDF of CMP and difference therebetween; forming time difference code; forming array of address codes corresponding to zero crossing moments of codes of USS passed ICF of CMP; determining zero crossing moment address code for codes of USS passed ICF of CMP closest to mutual correlation function (MCF) maximum address codes; selecting codes of USS passed ICDF of CMP corresponding to MCF maximum; forming MCF of selected part of codes of USS passed ICDF of CMP and signal shifted by 90° to primary USS; digitizing these MCF forming codes of time transmission of USS passed ICDF of CMP within sampling rate interval; determining accurate difference code of time intervals between USS passed ICDF of CMP; and determining CMP volume flow rate from a formula.