Micro-Coriolis Mass Flow Sensor Strain Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing micro-Coriolis mass flow sensors have limited design options for Coriolis tube geometry and are sensitive to water hammer.
Innovation Solution
A micro-Coriolis mass flow sensor with a rectangular or square loop shape and strain measurement devices on freely suspended portions of the Coriolis tube, allowing for a wider range of geometries and reduced sensitivity to water hammer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If capacitive readout is used in micro-Coriolis mass flow sensors, then displacement measurement is achieved, but the range of Coriolis tube geometry options is limited
Solution Approach 1:
The patent replaces capacitive readout (electrical field-based detection) with strain measurement devices (mechanical strain detection). This substitution enables a wider range of Coriolis tube geometries because strain gauges can be applied to various shapes including rectangular and square loops, whereas capacitive readout requires specific geometric configurations for proper operation.
2Measurement precision
If displacement measurement is used in micro-Coriolis mass flow sensors, then mass flow detection is achieved, but sensitivity to water hammer increases
Solution Approach 1:
The patent changes the measurement parameter from displacement to strain. By measuring strain (deformation) rather than displacement (position change), the detection system becomes less sensitive to water hammer effects. Water hammer causes transient displacement spikes, but strain measurement captures the actual mechanical stress on the tube, providing more stable and accurate mass flow detection during transient conditions.
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
Enables a broader range of design options for the Coriolis tube geometry and reduces sensitivity to water hammer, improving measurement accuracy and reliability.
Implementation Method 1
the detection means comprising one or more strain measurement devices configured for resistive readout being arranged in or on the Coriolis tube
Implementation Method 2
As a fluid flows in the vibrating tube, it induces Coriolis forces, proportional to the mass flow, which affect the tube motion and change the mode shape
Implementation Method 3
The vibration of the tube generated by the exciter takes place at a more or less fixed frequency which varies slightly as a function, amongst others, of the density of the medium flowing through the tube. The vibration frequency is almost always a natural frequency of the tube so that a maximum amplitude can be achieved with a minimum energy input
Data Source
Figure 1A~1C
Figure 1D~2
Figure 3A~3D
AI summary
The invention relates to a micro-Coriolis mass flow sensor, comprising a Coriolis tube having a fixed inlet and a fixed outlet, being fixed in tube fixation means, excitation means for oscillating the Coriolis tube about an excitation axis, detection means (8) for detecting, in use, at least a measure for movements of part of the Coriolis tube, characterized by the detection means (8) comprising one or more strain measurement devices (9, 11) configured for resistive readout being arranged in or on the Coriolis tube.