Measurement Of Liquid Viscosity Research Articles

ViscoCam

Dysphagia patients need to carefully control their intake liquid's viscosity to reduce choking and aspiration risks. However, accurate liquid viscosity measurement requires expensive rheometers still unavailable in daily life. Though the existing approximate testing methods are low-cost, they are not convenient for everyday use as they require either tedious procedures or dedicated apparatus. This paper presents ViscoCam, the first liquid viscosity classification system for dysphagia patients or carers, which only requires a smartphone. It is easy to operate, widely deployable, and robust for daily use. ViscoCam classifies visually indistinguishable liquid of various viscosity levels by exploiting the fact that the sloshing motion of viscous liquid decays faster than thin liquid. To perform a measurement, the user shakes a cup of liquid and their smartphone to induce the liquid sloshing motion. Then, ViscoCam senses the cup's motion using the smartphone's built-in accelerometer or microphone and infers liquid viscosity from the fluid surface motion captured by flashlight camera. To combat changes in camera position, lighting conditions, and liquid sloshing motion, a 3D convolutional neural network is trained to extract reliable motion features for classification. We evaluate ViscoCam's performance in classifying three levels in the IDDSI standard, which is the most up-to-date and internationally adopted one for dysphagia patients. Results show that ViscoCam achieves an overall accuracy of 96.52% in controlled cases. It is robust to unseen liquid heights or container sizes, and >81% accuracy is maintained under extreme testing cases.

2E3-1 Noncontact measurement of liquid viscosity in a soft container using free vibration after acoustic irradiation

2E3-1 Noncontact measurement of liquid viscosity in a soft container using free vibration after acoustic irradiation

A non-contact pneumoelectric device for liquid viscosity measurement

A non-contact pneumoelectric device for liquid viscosity measurement

Ultrasonic measurement of viscosity: Signal processing methodologies

This work deals with two alternative methodologies for data post-processing resulting from the ultrasonic shear-wave reflectance method used for liquid viscosity measurement. In the shear-wave reflectance method, the measurement principle is the small transference of energy to the liquid when the wave strikes a solid–liquid interface, causing a detectable change in the reflection coefficient. A measurement cell that uses mode conversion for the generation of the shear waves was employed and samples of five different substances were tested, covering a viscosity range of three orders of magnitude. Ultrasonic results were compared to the values obtained by conventional viscometry. Despite the wide range of viscosity and the different nature of the liquids, Newtonian behavior was observed with all samples at the working frequencies. This can be concluded from the coincidence between the values obtained by ultrasound and by the rotational viscometer. However, the viscosity values show an oscillating behavior when calculated for different frequencies along the band of the transducer. This oscillating behavior induces big errors when the viscosity is calculated at a single frequency, forcing the development of alternative methodologies. Two methodologies that calculate the reflection coefficient in a frequency band instead of a single frequency were analyzed, showing more accuracy and precision.

Liquid Viscosity Measurement Through a Drop Impact Event

Viscosity of liquids is an important property determining flow characteristics such as shear stress caused by a flow, and elongation and dripping of films and drops. Conventional techniques determine liquid viscosity from shear stress acting in a capillary tube, on a vibrating plate, or on a rotating cylinder. The disadvantages of the methods are its relatively long measurement time and large amount of samples required, and more importantly, its inapplicability for coagulating liquids whose viscosity increases with time. Here we develop an original liquid viscosity measurement technique that employs a drop impact on a solid surface. The measurement principle is based on the energy budget: An impacting drop spreads on a solid surface due to kinetic energy which is on the surface converted to the viscous dissipation and the surface tension energy. We can therefore deduce the viscosity from the inertial, the surface tension force and the maximum spreading diameter. The simplicity of the present technique enables us to overcome the problems of the conventional methods. In experiments, we measured the viscosity of glycerol aqueous solution drops using a high-speed camera and a laser sensor. In conclusion, we revealed the uncertainty of the present technique is approximately 10 %, which was evaluated both by uncertainty analysis and by experimentally comparing the viscosity with the ones obtained with an Ostwald viscometer.

A modified scaled variable reduced coordinate (SVRC)-quantitative structure property relationship (QSPR) model for predicting liquid viscosity of pure organic compounds

Liquid viscosity is an important physical property utilized in engineering designs for transportation and processing of fluids. However, the measurement of liquid viscosity is not always easy when the materials have toxicity and instability. In this study, a modified scaled variable reduced coordinate (SVRC)-quantitative structure property relationship (QSPR) model is suggested and analyzed in terms of its performance of prediction for liquid viscosity compared to the conventional SVRC-QSPR model and the other methods. The modification was conducted by changing the initial point from triple point to ambient temperature (293 K), and assuming that the liquid viscosity at critical temperature is 0 cP. The results reveal that the prediction performance of the modified SVRC-QSPR model is comparable to the other methods as showing 7.90% of mean absolute percentage error (MAPE) and 0.9838 of R 2. In terms of both the number of components and the performance of prediction, the modified SVRC-QSPR model is superior to the conventional SVRC-QSPR model. Also, the applicability of the model is improved since the condition of the end points of the modified model is not so restrictive as the conventional SVRC-QSPR model.

Analysis of Liquid Viscosity by Image Processing Techniques

Objective: In this paper, a technique is proposed for measurement of viscosity using the principle of dispersion of incident light with variation of liquid viscosity. The objective of the proposed technique is to design a non contact technique to analyze the characteristics of dispersed image using image processing for the light incident on liquid whose viscosity is to be measured. Methods: A camera is used to capture the background image of the refracted image. This captured image is processed by techniques like thresholding, filtering, and histogram to arrive at a quantified relation between viscosity and histogram values. To establish the relation an artificial neural network model is designed. Proposed neural network is trained by Levenburg Marquardt Algorithm, once trained it is tested with the real time system conditions. Findings: Once the neural network is designed, tests are conducted. Several samples of liquid are used with varying viscosity. From the obtained results it is clear that the proposed technique is able to measure viscosity accurately with a root mean percentage of error 2.01%. Application: From the obtained results it is clear that the proposed viscosity measurement technique can be used for measurement of liquid viscosity, even in dynamic flow conditions.

A structural tailored piezo actuated cantilever shaped 2-DOF resonators for viscosity and density sensing in liquids

Structural tailoring of cantilever shaped two degrees of freedom (2-DOF) resonators for the measurement of liquid viscosity and density is seldom explained. In this paper, a structural tailored 2-DOF cantilever shaped resonators for the determination of viscosity and density of liquids and its performance is investigated. The 2-DOF resonator consists of a trapezoidal shaped driver and absorber mass of identical frequency with a mass disparity. The driver and absorber mass are connected by a strong mechanical coupling unit which forms the 2-DOF trapezoidal cantilever resonant system (2-DOF TCR). The measurement principle is based on tracking the resonant characteristics of 2-DOF TCR system which depends on the viscosity and density of liquids it operates in. The system is evaluated for its performance in liquids of viscosity ranging from 0.23 mPas to 1400 mPas and density ranging from 713kg/m3 to 1261kg/m3. The resonant characteristics are compared with the existing 2-DOF rectangular cantilever resonant system (2-DOF RCR) and 1-DOF rectangular cantilever resonant system (1-DOF RCR) of same length. The theoretical results obtained from this study are in good agreement with the experimental results and the 2-DOF TCR system shows better sensitivity in determining the liquid viscosity and density.

Surface tension and liquid viscosity measurement for binary mixtures of R134a with R1234yf and R1234ze(E)

The surface tension and liquid kinematic viscosity of two binary refrigerant mixtures 1,1,1,2-tetrafluoroethane (R134a) (1) +2,3,3,3-tetrafluoroprop-1-ene (R1234yf) (2) and R134a (1) + trans-1,3,3,3-tetrafluoroprop-1-ene (R1234ze(E)) (2) were measured in the temperature range from 293 K up to the liquid–vapor critical point with the surface light scattering (SLS) method. The experimental data were correlated as a function of temperature and mole fraction of the pure components. For surface tension, the average absolute deviations are 0.019 mN∙m−1 for R134a + R1234yf and R134a + R1234ze(E). For liquid viscosity, the average absolute deviations are 0.96% and 1.16% for R134a + R1234yf and R134a + R1234ze(E), respectively.

Compressed Liquid Viscosity Measurements of HFE-7000, HFE-7100, HFE-7200, and HFE-7500 at Temperatures from (253 to 373) K and Pressures up to 30 MPa

The compressed liquid viscosities of heptafluoropropyl methyl ether (HFE-7000), methoxy-nonafluorobutane (HFE-7100), ethoxy-nonafluorobutane (HFE-7200), and 2-trifluoromethyl-3-ethoxydodecafluorohexane (HFE-7500) were measured using a vibrating- wire viscometer over the temperature range of (253 to 373) K and at pressures from (0.1 to 30) MPa. The combined expanded uncertainty of the reported viscosity is about 2 % with a confidence level of 0.95 (k = 2). The experimental data were correlated with the empirical Andrade–Tait equation which could reproduce the results with average absolute percentage deviations of 0.44 %, 0.38 %, 0.56 %, and 0.56 %, respectively.

Development, implementation, and characterization of a standalone embedded viscosity measurement system based on the impedance spectroscopy of a vibrating wire sensor

This paper presents an embedded liquid viscosity measurement system based on a vibrating wire sensor. Although multiple viscometers based on different working principles are commercially available, there is still a market demand for a dedicated measurement system capable of performing accurate, fast measurements and requiring little or no operator training for simple systems and solution monitoring. The developed embedded system is based on a vibrating wire sensor that works by measuring the impedance response of the sensor, which depends on the viscosity and density of the liquid in which the sensor is immersed. The core of the embedded system is a digital signal processor (DSP) which controls the waveform generation and acquisitions for the measurement of the impedance frequency response. The DSP also processes the acquired waveforms and estimates the liquid viscosity. The user can interact with the measurement system through a keypad and an LCD or through a computer with a USB connection for data logging and processing. The presented system is tested on a set of viscosity standards and the estimated values are compared with the standard manufacturer specified viscosity values. A stability study of the measurement system is also performed.

Surface tension and liquid viscosity measurement of ethyl fluoride (R161) under saturation condition

Surface light scattering (SLS) has been used for the simultaneous determination of surface tension and liquid kinematic viscosity of ethyl fluoride (R161) under saturation conditions in the temperature ranges between 293K and very close to the critical temperature with the expanded uncertainties(k=2) of ±2% for the liquid kinematic viscosity and ±1.5% for the surface tension. In addition, the surface tension of R161 was also measured over the temperature range from (244 to 334)K using the differential capillary rise method. All the surface tension and viscosity results were correlated as a function of temperature, and the average absolute deviations between the experimental and calculated values were 0.04mNm−1 and 1.11%, respectively.

Precision density and viscosity measurement using two cantilevers with different widths

We introduce a novel method for fast measurement of liquid viscosity and density using two cantilevers with different geometries. Our method can be used for real-time monitoring in lab on chip systems and offer high accuracy for a large range of densities and viscosities. The measurement principle is based on tracking the oscillation frequencies of two cantilevers with a phase-locked loop (PLL) and comparing with reference measurements with a known fluid. A set of equations and a simple algorithm is developed to relate the density and the viscosity to the frequency shifts of the cantilevers. We found that the effect of the density and the viscosity can be well separated if cantilevers have different widths. In the experiments, two Nickel microcantilevers (widths 25μm and 100μm, length: 200μm, thickness: 1.75μm) were fully immersed in the liquid and the temperature was controlled. The actuation was using an external electro-coil and the oscillations were monitored using laser Doppler vibrometer. Thus, electrical connections to the cantilevers are not required, enabling measurements also in conductive liquids. The PLL is used to set the phase difference to 90° between the actuator and the sensor. Calibration measurements were performed using glycerol and ethylene glycol solutions with known densities and viscosities. The measurement error with the new method was lower than 3% in density in the range 995–1150kg/m3 and 4.6% in viscosity in the range 0.935–4mPa.s. Based on the signal-to-noise ratio, the minimum detectable difference in the viscosity is 1μPa.s and the density is 0.18kg/m3. Further improvements in the range and the accuracy are possible using 3 or more cantilevers with different geometries.

Application of Magnetic Field Method for Measuring Lubricant Viscosity

This study presents an application of Hall Effect sensor to assess the viscosity of industrial lubricant by using reference metal particles with the dimension ranging from 1 µm to 100 µm and the mass ranging from 0.1 g to 1 g as the essential modules of the developed system. Hall Effect sensor is a small electronic component which is easy for installing, analyzing, and processing due to electrical output generated. Moreover, the cost of this developed method is lower than other means of viscosity tests. At present, there are several studies on viscosity and quality tests of industrial lubricants such as Ultrasonic measurement of viscosity of liquids [1], Photoacoustic measurement of liquid viscosity [2], Measurement of magnetic viscosity in NdFeB [3], A viscosity and density meter with a magnetically suspended rotor [4], Capacitive sensor [5], IR-Absorption [6], and Optical fiber sensing [7]. In this study, the measurement methodology was considered only the lubricant viscosity at the temperature of 26 °C and then compared the results to the viscosity classification which is the reference of lubricant characteristic. Moreover, the lubricant types namely SAE 15W-40, SAE 20W-50 and ISO VG 100 were selected as the case studies.

2P2-6 Measurement of Liquid Viscosity near a Wall Using Optoacoustic Interaction(Poster Session)

2P2-6 Measurement of Liquid Viscosity near a Wall Using Optoacoustic Interaction(Poster Session)

Measurement of Liquid Viscosity and Density Using Single Piezoelectric Resonator with Two Vibration Modes

Measurement of Liquid Viscosity and Density Using Single Piezoelectric Resonator with Two Vibration Modes

Measurement of Liquid Viscosity and Density Using Single Piezoelectric Resonator with Two Vibration Modes

We report the results of an experiment on measuring the viscosities and densities of several liquids using a single piezoelectric sensor, since only the numerical results obtained by finite element analysis were reported in our previous paper. The novelty of the sensor is that the viscosity and density can be inferred simply by measuring resonance frequencies in liquid for the vibration in the tangential and normal directions with respect to the contact surface between the sensor and the liquid, while the method suggested as reference requires measurements of resonance frequency and damping of a single vibration mode. By comparing the viscosities and densities measured by the proposed and conventional methods using food oil, the densities were found to correspond to the values measured using a weight meter with an error within 1% and the viscosity was evaluated to be higher than that measured using a viscometer with an error within 10%. The results suggest the possibility of measuring liquid density and viscosity by the proposed method.

Viscosity measurements of liquids under pressure by using the quartz crystal resonators

A quartz crystal viscometer has been developed for measuring viscosity in liquids under pressure. It employs an AT-cut quartz crystal resonator of fundamental frequency 3 MHz inserted in a variable-volume vessel designed for working up to 80 MPa. Viscosity is determined by two methods from resonance frequency and bandwidth measurements along up to eight different overtones. The resonance frequency allows an absolute measurement of the viscosity but leads to an accuracy limited to 5% whereas the bandwidth technique which works in a relative way provides an accuracy of 2%. The techniques were tested by carrying out measurements in two pure compounds: heptane and toluene. Measurement results demonstrate the feasibility of the technique in this viscosity range. The apparatus was also used to determine the viscosity of n-decane with dissolved methane. The results obtained with these mixtures reveal the applicability of the apparatus for reservoir fluids study.

Application of SH surface acoustic waves for measuring the viscosity of liquids in function of pressure and temperature

Viscosity measurements were carried out on triolein at pressures from atmospheric up to 650 MPa and in the temperature range from 10 °C to 40 °C using ultrasonic measuring setup. Bleustein–Gulyaev SH surface acoustic waves waveguides were used as viscosity sensors. Additionally, pressure changes occurring during phase transition have been measured over the same temperature range. Application of ultrasonic SH surface acoustic waves in the liquid viscosity measurements at high pressure has many advantages. It enables viscosity measurement during phase transitions and in the high-pressure range where the classical viscosity measurement methods cannot operate. Measurements of phase transition kinetics and viscosity of liquids at high pressures and various temperatures (isotherms) is a novelty. The knowledge of changes in viscosity in function of pressure and temperature can help to obtain a deeper insight into thermodynamic properties of liquids.

Photoacoustic measurement of liquid viscosity

In this letter, we report on the use of photoacoustic method to measure the viscosity of viscous liquids. The theoretical and experimental study was performed on the influence of viscosity effects on photoacoustic generation. We provide evidence that the frequency spectrum of photoacoustic signal is precisely related to the viscosity. Measurements are validated on different water–glycerol mixtures. Good agreement between theoretical and experimental results is obtained. This present method provides an insight into in situ viscosity measurements, which has potential for noninvasive detection of blood viscosity.