Vibronic Density Sensing Using Phase-Shift Damping Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vibronic sensors face limitations in accurately determining density and viscosity of media, particularly at high viscosities, due to the assumption that measurements are independent of viscosity for a specific phase shift, which restricts their applicability.
Innovation Solution
A method and device using a vibronic sensor that determines density and viscosity by setting a predefinable phase shift between excitation and receive signals, allowing for the determination of attenuation and frequency, and employing an analytical model to calculate density and viscosity, regardless of viscosity, using a single or multiple phase shifts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a specific phase shift is assumed for viscosity-independent measurement, then density determination is simplified, but measurement accuracy deteriorates at high viscosities
Solution Approach 1:
The patent changes the measurement parameters by using multiple phase shifts instead of a single phase shift assumption. By measuring at different phase shifts and using the ratio of attenuation values, the method eliminates viscosity's confounding effect on density measurement while maintaining accuracy at high viscosities.
Solution Approach 2:
The patent introduces an intermediary approach by using the ratio of attenuation values at different phase shifts as a mediator parameter. This ratio serves as a viscosity-independent characteristic that enables accurate density determination without being affected by viscosity variations.
2Measurement precision
If multiple phase shifts are used to eliminate viscosity influence, then measurement accuracy improves, but measurement speed deteriorates
Solution Approach 1:
The patent applies partial action by using only two specific phase shifts (0° and 90°) rather than continuously scanning through all possible phase shifts. This selective approach at predefined phase shift values achieves viscosity-independent measurement while maintaining fast measurement speed.
3Measurement precision
If viscosity influence is eliminated through multiple measurements, then density determination accuracy improves, but device complexity increases
Solution Approach 1:
The patent replaces complex mechanical or hardware-based viscosity compensation mechanisms with an analytical solution. By using mathematical relationships between attenuation values at different phase shifts, the system eliminates viscosity influence through calculation rather than through complex physical compensation mechanisms.
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 accurate and universal determination of density and viscosity across various media, including highly viscous ones, with increased speed and simplified measurement principles compared to prior art.
Implementation Method 1
For example, the drive/receiver unit can be a piezoelectric element
Implementation Method 2
the drive/receiver unit can be a piezoelectric element... the mechanically vibrating unit is excited to mechanical vibrations by means of an electrical excitation signal. Conversely, the drive/receiver unit can receive the mechanical vibrations of the mechanically vibrating unit and convert them into an electrical reception signal
Implementation Method 3
the viscosity of a medium can be determined using a vibronic sensor based on the frequency-phase curve (Φ=g(ω)). This method is based on the dependence of the damping of the vibrating unit on the viscosity of the respective medium
Data Source
Figure 1
Figure 2
AI summary
The invention relates to a method for determining and/or monitoring the density (p) and/or the viscosity (v) of a medium (3) in a container (2) by means of a vibronic sensor (1), and a corresponding sensor (1). A vibrateable unit (4) is caused to mechanically vibrate by means of an electrical excitation signal (UA), and the mechanical vibrations of the mechanically vibrateable unit (4) are received and converted into an electrical receive signal (UE). In addition, the excitation signal (UA) is generated from the receive signal (UE) in such a way that at least one predeterminable phase shift (Δφ) occurs between the excitation signal (UA) and the receive signal (UE), wherein a frequency (f) of the excitations signal (UA) is determined from the receive signal (UE) with the occurrence of the predeterminable phase shift (Δφ). Furthermore, a damping (D) and/or a damping (D)-dependent variable is/are determined from the receive signal (UE) with the occurrence of the predeterminable phase shift (Δφ), and the density (p) and/or the viscosity (v) of the medium is/are determined at least from the damping (D) and/or the damping (D)-dependent variable, and from the frequency (f) of the excitation signal (UA).