Flow Rate Measuring Device Waveform Portion Pulsation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current flow rate measuring devices face challenges in achieving high accuracy, particularly with engines that generate large pulsation, as existing solutions fail to effectively handle counter flow elements and swirls near the cylindrical portion openings, leading to measurement errors.
Innovation Solution
The flow rate measuring device incorporates a cylindrical portion with a waveform portion at its opening, featuring protrusions and recessed portions that divide the main flow and measurement flow into multiple streams, facilitating mixing and preventing swirls from combining, while allowing counter flow elements to be drawn in, thus enhancing measurement accuracy and discharge efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a conventional flow rate measuring device is used, then the device structure is simple, but the measurement precision deteriorates under large pulsation conditions
Solution Approach 1:
The cylindrical portion is divided into multiple segments along the flow direction, with each segment containing protrusions and recessed portions. This segmentation allows the device to handle different flow conditions (including counter flow elements) in different segments, improving measurement precision under pulsation without requiring a completely complex redesign of the entire device.
Solution Approach 2:
The cylindrical portion incorporates localized protrusions and recessed portions at specific positions rather than uniform modifications throughout. This local quality approach addresses the specific problem of swirl formation at the opening while maintaining simplicity in other regions, resolving the contradiction between measurement precision and device complexity.
2Measurement precision
If the cylindrical portion opening is modified to prevent swirls, then measurement precision improves, but the device complexity increases
Solution Approach 1:
The cylindrical portion incorporates curved surfaces and rounded transitions instead of sharp edges or complex angular structures. The protrusions and recessed portions feature smooth curved profiles that effectively manage swirl formation while maintaining manufacturing simplicity and avoiding excessive geometric complexity.
3Measurement precision
If a conventional cylindrical portion is used, then the device is easy to manufacture, but counter flow elements are not effectively handled
Solution Approach 1:
The cylindrical portion design allows the flow pattern to dynamically adapt to different operating conditions. The protrusions and recessed portions create flow separation and recombination zones that automatically adjust to handle both normal flow and counter flow elements, improving measurement precision without requiring complex active control mechanisms that would complicate manufacturing.
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 improves the accuracy of flow rate measurements by effectively managing swirls and counter flow elements, even under conditions of large pulsation, while being cost-effective and versatile, with the waveform portion design allowing for easy manufacturing and robustness across various flow speeds.
Implementation Method 1
The waveform portion has a shape that divides the main flow guided by the cylindrical portion into a plurality of main flows and that divides the measurement flow guided by the cylindrical portion into a plurality of measurement flows
Implementation Method 2
The cylindrical portion includes an outer circumferential surface, which guides the main flow, and an inner circumferential surface, which guides the measurement flow
Data Source
AI summary
A flow rate measuring device measures a flow rate of a main flow flowing through a duct. The flow rate measuring device includes a bypass passage, a flow rate sensor, and a measurement body. The measurement body includes a measurement flow inlet opening toward an upstream side of the duct and a cylindrical portion opening toward a downstream side of the duct. The cylindrical portion is disposed to cover the measurement flow outlet. The cylindrical portion includes an outer circumferential surface guiding the main flow and an inner circumferential surface guiding the measurement flow. The cylindrical portion includes a waveform portion formed in an edge side of an opening of the cylindrical. The waveform portion divides the main flow guided by the cylindrical portion into a plurality of main flows and divides the measurement flow guided by the cylindrical portion into a plurality of measurement flows.