Ultrasonic Flow Meter with Swirl-Sensitive Acoustic Paths
Solution Overview
Problem
Ultrasonic flow measurement devices face challenges in achieving high accuracy and reliability while maintaining a simple design and minimizing the number of transducers, particularly in complex piping structures where flow profiles are distorted by swirl, cross flow, and asymmetry.
Innovation Solution
The device employs multiple pairs of ultrasonic transducers arranged in specific acoustic paths, including swirl-sensitive equilateral triangular and half-square configurations, with shared transducers to increase the interrogation area and reduce signal interference, allowing for accurate flow velocity and throughput measurement with a minimal number of transducers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple transducers are used to increase interrogation area and improve measurement accuracy, then measurement precision and reliability are improved, but device complexity and cost increase
Solution Approach 1:
The patent combines multiple acoustic paths (triangular, square, diagonal) into a single integrated transducer arrangement. The first and second transducers work together to define multiple acoustic paths including triangular paths for swirl measurement and square/diagonal paths for flow profile characterization, eliminating the need for separate transducer sets for each function.
Solution Approach 2:
The transducer arrangement is designed to perform multiple functions simultaneously: measuring swirl velocity via triangular paths, characterizing flow profiles via square and diagonal paths, and determining flow direction. This multi-functionality reduces the overall number of transducers needed while maintaining comprehensive measurement capabilities.
2Measurement precision
If complex acoustic path configurations are used to improve accuracy in distorted flow profiles, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The acoustic measurement system is segmented into distinct path types: triangular paths for swirl measurement, square paths for flow profile characterization, and diagonal paths for additional flow direction information. Each path type is optimized for specific measurement objectives, allowing the system to handle distorted flow profiles through coordinated use of simplified path segments.
Solution Approach 2:
The patent employs asymmetric acoustic paths including diagonal paths that are not symmetric with respect to the conduit centerline. This asymmetry allows the system to detect and characterize asymmetric flow distortions, cross flows, and swirl patterns that would be invisible to symmetric path configurations.
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 configuration enhances the accuracy and reliability of flow measurements by providing comprehensive information about the flow profile and covering a larger conduit cross-section, while maintaining a relatively simple and cost-effective device design.
Implementation Method 1
transmitting ultrasonic sound waves between a transmitter and a receiver
Implementation Method 2
The transit time of the ultrasonic waves is measured
Implementation Method 3
the ultrasonic wave transmitted by the transmitter reflects twice at the inner conduit wall prior to being received by the receiver
Implementation Method 4
The transit time of the ultrasonic waves is measured. From the difference in transit time of the downstream directed ultrasonic wave and the upstream directed wave an average flow velocity or throughput can be calculated
Data Source
Figure 1~2
Figure 3~4
AI summary
A device for determining a flow characteristic of a fluid in a conduit comprises a conduit body (10), a first pair of first ultrasonic transducers (16, 18) defining a first swirl sensitive acoustic path (20) and a second pair of second ultrasonic transducers (24, 26) defining a second swirl sensitive acoustic path (28) , a third pair of third ultrasonic transducers (30, 32) and a fourth pair of fourth ultrasonic transducers (36, 38) the transducers (30, 32) of the third pair being positioned diametrically opposite to each other at the wall (14) of the conduit body (10) such that the third transducers (30, 32) define a third acoustic path (34) having a single reflection against the inner (12) wall of the conduit body (10) and the transducers (36, 38) of the fourth pair being positioned diametrically opposite to each other such that the fourth transducers (36, 38) define a fourth acoustic path (40), wherein the transducers (16, 18; 24, 26; 30, 32; 36, 38) are capable of acting individually as a transmitter and receiver for transmitting ultrasonic waves along their respective acoustic paths and receiving thereof, means (42, 44) for measuring the transit times of transmitted ultrasonic waves and for determining a flow characteristic from the measured transit times.