Speed Of Sound Measurements Research Articles

Effect of nonideal fluid behavior on the jet mixing process under high-pressure and supersonic flow conditions

The mixing process of extremely underexpanded supercritical jets into a gaseous environment is studied. The focus lies on the influence of the nonideal fluid behavior on the mixing process. Numerical simulations are conducted for eight different injection conditions where experimental sound speed measurements are available. Overall, a very good agreement between simulations and experiments is found. A comparison of the real-gas and the ideal-gas closures shows the necessity to account for nonideal fluid behavior. The application of the ideal-gas law results in an incorrect energetic state which most prominently leads to an overestimation of the post-shock temperature by 70 K. The wrong energetic state yields erroneous thermodynamic properties in the mixing region. Finally, a mixture model is deduced enabling the prediction of mixture properties. As independent measurements of mass/mole fractions are not available, this evaluation procedure is a first attempt to numerically predict the mixture composition in underexpanded jets.

Mixed Micellization Behavior of (Chlorpromazine Hydrochloride + Cetyltrimethylammonium Bromide) System in Aqueous Solutions of Glycine

AbstractWe have examined the mixed micellar behavior of {amphiphilic drug; chlorpromazine hydrochloride (CPZ) + cationic surfactant; cetyltrimethylammonium bromide (CTAB)} at varying mole fractions of CPZ (αCPZ = 0.2, 0.4, 0.6, and 0.8) in (0.1, 0.3, and 0.5) mol kg−1 glycine(aq) solutions at 298.15, 308.15, and 318.15 K, by using conductometric, volumetric, isentropic compressibility, UV–visible absorbance, fluorescence, and dynamic light scattering (DLS) techniques. The critical micelle concentration (CMC) values obtained from above measurements have been utilized to calculate the thermodynamic parameters (ΔG°m, ΔH°m, and ΔS°m) and degree of ionization (α) at studied temperatures and concentrations. The partial specific volume (φv), partial specific isentropic compression (φκ), and isentropic compressibility (κs) have been calculated from the experimental density and speed of sound measurements and the results have been used to elucidate different interactions occurring in these systems. These results are further supported by UV–visible absorbance and fluorescence spectroscopic studies. The hydrodynamic diameters (Dh) of the mixed micellar system have been measured from the DLS studies. Thermodynamic and spectroscopic studies depict the dominance of hydrophobic/hydrophilic‐hydrophobic interactions between the alkyl (R = C16H33) chain of CTAB or hydrophobic tricyclic scaffolding of CPZ/Br−/N+‐CH3 group of CTAB or hydrophilic group i.e., tertiary amine portion of CPZ with hydrophobic group of glycine.

Speed of sound measurement for HFO refrigerants in liquid phase:

Speed of sound measurement for HFO refrigerants in liquid phase:

A Continuous-Wave Method for Sound Speed Measurement Based on an Infinite-Echo Model

A Continuous-Wave Method for Sound Speed Measurement Based on an Infinite-Echo Model

Defining disease progression in Chinese mainland people: Association between bone mineral density and knee osteoarthritis.

ObjectiveTo evaluate change in bone mineral density (BMD) during development of knee osteoarthritis (OA) in elderly Chinese community residents. Further, to monitor disease progression by recording speed of sound (SOS), one parameter of BMD provided by quantitative ultrasound measurement.MethodsA total of 4173 community residents of the Chinese mainland were organized to complete questionnaires and relevant measurements, including anthropometry, radiology and quantitative ultrasound (QUS). SOS measurements of the distal radius were acquired using QUS measurements. The Kellgren-Lawrence (KL) grade of knee OA was evaluated by two experienced radiographers using X-rays. Finally, a general linear models analysis was performed to determine potential relationships. Further, the area under the receiver operating characteristic curve (ROC AUC) was applied to assess the distinction model.ResultsThe SOS score in the OA group was significantly lower than that in the control group (p ​< ​0.001). However, after adjustment for age and body mass index (BMI), no significant difference was observed in the male population (p ​＝ ​0.841), while a significantly lower SOS score presented in knee OA participants in the female population (p ​＝ ​0.033). A turning point in SOS scores, from increasing to decreasing trends, occurred around KL grade 2; the SOS score gradually increased with progression in participants from KL grades 0 to 2, whereas the SOS score presented a significant decrease in participants with KL grades 3 and 4. The AUC for the model to distinguish OA progression was 0.891.ConclusionThere was a non-linear and stage-specific association between SOS score and knee OA, which presented a positive relationship in early stages, but a negative relationship in advanced stages. A decline of SOS score in knee OA patients in early stages should alert clinicians to the possibility of disease progression.The Translational potential of this articleIn the present study, the relationship between OA and BMD had established by SOS. The results suggested that close monitoring of SOS in elderly Chinese communities residents with knee OA could alert disease progression involvement by an easily accessible method, and help early referral to orthopedist consultation for further examination and treatment.

Elastic properties of polyethylene from high pressure sound speed measurements

Polyethylene is a widely used plastic exhibiting a large range of properties that depend on molecular weight, crystallinity, chain branching, and cross-linking. In this study, the sound speeds and elastic properties of a variety of commercially available polyethylene materials were experimentally determined using the pulse-echo ultrasound technique. In situ pressure dependent measurements, including ultrasound time of flight, x-ray diffraction, and x-ray radiography, were performed using a Paris-Edinburgh large volume press at the High Pressure Collaborative Access Team (HPCAT), beamline 16-BM-B at the Advanced Photon Source. Polyethylene sound speed and elastic moduli were found to increase with increasing pressure. The zero pressure orthorhombic phase was found to transform to monoclinic at low pressures of ~0.1 GPa.

Investigating shock melting of metals through time-resolved x-ray diffraction of cerium

Time-resolved x-ray diffraction (XRD) was used to examine the behavior of Ce under shock loading to stress states up to 22 GPa that span the shock-melt transition. Experiments reported here observed Ce held at a steady state for ∼500 ns prior to being uniaxially released to ambient pressure. Time-resolved XRD shows a constant diffraction pattern over the duration of the steady state with rapid solidification occurring on release. Cerium was found to remain crystalline as Poisson's ratio (ν) increases in the α-phase with incipient melt observed in XRD once ν reaches 0.5. Diffraction results along with sound speed measurements limit melt completion to be between 12 and 14 GPa, significantly lower than previously expected. The XRD results add confidence to previous methods used to define incipient melt and help to define a method to constrain the melt region along the Hugoniot independent of a light source.

Simple Sound Speed Measurement Method for Liquids and Castable Phantom Materials

The speed of sound $c$ is an important property of materials and fluids. Ultrasonic imaging is based on the assumed values of $c$ , and the characterization of various phantom materials includes measurements of their $c$ values. Measurements of $c$ , to date, have required specialized setups that are not always readily available. The development of a simple alternative allows laboratories to measure $c$ with a minimum of specialized equipment. In this article, a method using only a polypropylene (or other plastic) test tube, fishing line, a level, a sewing or suture needle, sodium chloride, and a conventional ultrasonic B-mode imager is described that allows one to measure $c$ readily. The measurement is based on the difference between the apparent and actual distances separating two fishing line targets embedded within a test tube. The liquid or gel being measured is poured into the test tube and B-mode ultrasonic images are obtained using a conventional clinical imager. This method was tested on seven samples of saline solutions with varying salt concentrations, pure ethanol, and a tissue-mimicking gel to verify its accuracy over a broad range (1144–1700 m/s) of reference values. Sound speed measurements were, on average, 100.4% ± 0.86% of published values. No single measurement had a deviation exceeding 2.4%. The measurement of sound speed is simplified and may be accurately performed with minimal equipment.

Whole Breast Sound Speed Measurement from US Tomography Correlates Strongly with Volumetric Breast Density from Mammography.

To assess the feasibility of using tissue sound speed as a quantitative marker of breast density. This study was carried out under an Institutional Review Board-approved protocol (written consent required). Imaging data were selected retrospectively based on the availability of US tomography (UST) exams, screening mammograms with volumetric breast density data, patient age of 18 to 80 years, and weight less than 300 lbs. Sound speed images from the UST exams were used to measure the volume of dense tissue, the volume averaged sound speed (VASS), and the percent of high sound speed tissue (PHSST). The mammographic breast density and volume of dense tissue were estimated with three-dimensional (3D) software. Differences in volumes were assessed with paired t-tests. Spearman correlation coefficients were calculated to determine the strength of the correlations between the mammographic and UST assessments of breast density. A total of 100 UST and 3D mammographic data sets met the selection criteria. The resulting measurements showed that UST measured a more than 2-fold larger volume of dense tissue compared to mammography. The differences were statistically significant (P < 0.001). A strong correlation of rS = 0.85 (95% CI: 0.79-0.90) between 3D mammographic breast density (BD) and the VASS was noted. This correlation is significantly stronger than those reported in previous two-dimensional studies (rS = 0.85 vs rS = 0.71). A similar correlation was found for PHSST and mammographic BD with rS = 0.86 (95% CI: 0.80-0.90). The strong correlations between UST parameters and 3D mammographic BD suggest that breast sound speed should be further studied as a potential new marker for inclusion in clinical risk models.

Detecting muscle activation using ultrasound speed of sound inversion with deep learning.

Functional muscle imaging is essential for diagnostics of a multitude of musculoskeletal afflictions such as degenerative muscle diseases, muscle injuries, muscle atrophy, and neurological related issues such as spasticity. However, there is currently no solution, imaging or otherwise, capable of providing a map of active muscles over a large field of view in dynamic scenarios.In this work, we look at the feasibility of applying longitudinal sound speed measurements to the task of dynamic muscle imaging of contraction or activation. We perform the assessment using a deep learning network applied to prebeamformed ultrasound channel data for sound speed inversion.Preliminary results show that dynamic muscle contraction can be detected in the calf and that this contraction can be positively assigned to the operating muscles. Potential frame rates in the hundreds to thousands of frames per second are necessary to accomplish this.

Ultrasound speed study of the ternary liquid mixture (water + ethanol + 1-propanol) at T = 293.15 K and P = 0.1 MPa

Sound speed measurements in 42 ternary aqueous mixtures of ethanol plus 1-propanol and new measurements in the three binary mixtures, composed by the three same components, were made at T = 293.15 K and P = 0.1 MPa. Following the volumetric study recently published, a compressibility analysis is now presented in order to complement our previous work, mainly based on derived properties such as excess partial molar isentropic compressions of the three components and their limiting values. As far as we know curves for limiting excess partial molar isentropic compressions of the i component in the ternary mixture were derived for the first time. Transfer functions of these limiting values when water and alcohol molecules are transferred from the aqueous binary to the ternary mixture, are presented and interpreted in terms of hydrophobic hydration and H-bonding effect.

Measurements of Density and Sound Speed in Mixtures Relevant to Supercritical CO2 Cycles

Abstract The objective of this research is to validate properties of mixtures relevant to supercritical carbon dioxide (sCO2) power cycles. Direct-fired sCO2 cycles are a promising technology for the future power generation systems. The working fluid of sCO2 cycles will be near and above critical point of CO2. One of the challenges is that the simulation of mixtures should consider real gas behavior. Expected operating conditions of Allam cycles reach up to 300 bar and 1000 °C. Characterizing the mixtures at the extreme conditions is an important issue in current researches and industrial applications. Thermophysical properties of mixtures may be beyond the valid range of the widely used database such as NIST REFPROP. Experimental data of mixture properties in the literature are limited which is necessary to develop high-fidelity design tools for sCO2 power cycles. We measured the density and sound speed of several multi-component mixtures. A temperature-controlled high-pressure test cell was used for the density measurements. Sound speed was measured by resonant frequency detection using an external speaker and a piezoelectric pressure sensor. Mixtures studied in this work include carbon dioxide, methane, oxygen, and water vapor. Properties of pure CO2 were measured to show the validity of our technique. Compositions were selected to be close to frozen mixtures at the inlet, mid-progress, and exhaust conditions of a model sCO2 combustor in the previous numerical simulation work. Corresponding reaction progress variables (RPV) were RPV = 0, 0.5, and 1. Temperature and pressure conditions of experiments are 310–450 K and 0–150 bar. In our study, density and sound speed from the NIST REFPROP database agree with experimental measurements within the range of our measurement uncertainties.

Volumetric and isentropic compressibility behaviour of ionic liquid, tetrapropylammonium bromide in some inorganic salts aqueous systems at T = (293.15 to 318.15) K

ABSTRACT In this work, to obtain evidence about the salting-out effect, a set of thermophysical properties, namely, density and speed of sound measurements were determined for the systems containing the ionic liquid tetrapropylammonium bromide and some inorganic salts at temperatures from T = 298.15 to 318.15 K and ambient pressure. For the investigated systems, the apparent molar volumes and apparent molar isentropic compressibilities at infinite dilution have been calculated at each temperature using the Masson equation. For all of the systems investigated the intermolecular interactions are weaker and also increase regularly with an increase in temperature. The values of TPAB are both negative and positive. For low concentrations, the isentropic compressibilities decrease with an increase in temperature. At a fixed temperature, the isentropic compressibilities also decreased with an increase in concentration of the solute.

Measurements of the density, speed of sound, viscosity and derived key thermodynamic properties of geothermal waters from East Turkey

Density, speed of sound, and viscosity of natural geothermal waters from the East Turkey Geothermal Field have been measured over the temperature range from 278 to 363 K and at atmospheric pressure. The measurements were made using the Anton Paar DSA 5000 M sound-speed analyzer and the Stabinger SVM3000 viscometer for two natural geothermal water samples from the Keklik Mağarasi and Afyon wells. A sound-speed analyzer (Anton Paar DSA 5000 M) was used to simultaneously measure of the speed of sound and the density of the same geothermal water samples. The standard uncertainty of the density, viscosity, and speed of sound measurements is estimated to be 0.01%, 0.25%, and 0.05%, respectively. Measured values of density and speed of sound were used to calculate other derived key thermodynamic properties of the geothermal waters, which are very important for environmental impact optimization of a geothermal energy production operation. The properties measured at atmospheric pressure have been used as reference data for prediction of high-pressure properties of the geothermal waters.

Experimental Characterization of a Piezoelectric Leaf-Cell Sensor for Simultaneous Fluid Density and Sound Speed Measurement

Measurement of a fluid mixture's bulk compressibility (i.e., simultaneous measurement of the fluid's sound speed and density) allows access to more underlying chemometric information about the mixture's multiphase composition than can currently be retrieved with single-mode sensor measurements, that is, those providing only one of either fluid density or fluid sound speed. Here, we summarize recent research to develop a sensor which provides simultaneous and congruent measurement of fluid density and sound speed, thus giving access to downhole borehole parameters such as oil/water volume fraction, gas-oil-ratio (GOR), live-oil density and compressibility, and dead-oil API.

Temperature-Dependent Thermodynamic Properties of Amino Acids in Aqueous Imidazolium-Based Ionic Liquid

Molecular interactions of amino acids with ionic liquids are significant to study the molecular stability and physicochemical properties of amino acids. Mixtures of amino acids l-leucine and N-acetyl-l-leucine + (0.005, 0.010, 0.030, and 0.050 mol·kg–1) aqueous solution of ionic liquid (1-butyl-3-methylimidazolium chloride) at temperature T = (288.15, 298.15, 308.15, and 318.15 K) have been studied by density and speeds of sound measurements. Volumetric properties have been obtained by utilizing data of density. Volumetric properties include apparent molar volumes, partial molar volumes at infinite dilution, limiting partial molar volumes of transfer at infinite dilution, apparent molar expansibility, etc. Similarly, speeds of sound measurements are utilized to calculate corresponding parameters like apparent molar isentropic compression, Kϕ,s, apparent molar isentropic compression at infinite dilution, Kϕ,s0, and transfer compressibility at infinite dilution ΔKϕ,s0. Results confirmed the predominance of ...

Thermodynamic Temperature Measurements from the Triple Point of Water up to the Melting Point of Gallium

A new acoustic gas thermometry (AGT) system, which introduces a 1-L quasi-spherical resonator (QSR) made of oxygen-free copper, was built at the National Metrology Institute of Japan (NMIJ/AIST). The inner surface of the new QSR was machined using a diamond-turn tool. Improvement in the pressure measurement was introduced to allow direct measurement of the gas pressure in the resonator. The new AGT system was evaluated based on the measurement of the speed of sound in argon at the triple point of water and the melting point of gallium under the pressure range from 700 kPa down to 50 kPa. Based on these speed of sound measurements, the thermodynamic temperatures at the melting point of gallium were determined. The speed of sound measurements at isotherms of 283.15 K and 293.15 K were also conducted, and the related thermodynamic temperatures were determined. Based on the measured thermodynamic temperature T, the values of difference between T and the temperature T90 based on the International Temperature Scale of 1990 (ITS-90), (T − T90), along with the associated uncertainties, were calculated. The (T − T90) obtained in the present work were 1.3 ± 0.7 mK, 2.7 ± 0.8 mK, and 4.1 ± 0.8 mK for T90 of 283.15 K, 293.15 K, and 302.9146 K, respectively. These values were found to be in agreement within the estimated uncertainty with the currently reported values that exist in temperature range overlapping with the present work.

Research on Wind Noise Estimation Method by Synchronous Measurement of Low Frequency Sound and Wind Speed

Research on Wind Noise Estimation Method by Synchronous Measurement of Low Frequency Sound and Wind Speed

Fiber Optic Acoustic Vibration Sensors for Ultrasound Measurement in Low-Pressure CO₂ Environment

The detection of acoustic signals in the Martian environment is significant to understand the issues such as the evolution of the universe, structure of matter, origin of life, and future migration of humans. We proposed a method for testing ultrasonic wave by using fiber-optic Fabry-Perot vibration sensors in a low-pressure CO 2 environment. We conducted high-precision sound wave amplitude and speed measurement tests with different center frequencies at 21, 25, 34, and 40 kHz under different gas compositions, pressures, and distances. Results showed that under the conditions of 15 °C and gas pressure in the range of 600 Pa to 1 MPa, the measured average sound velocity of ultrasonic signals at each frequency was 268.79 m/s in the CO 2 environment, which was lower than the velocity of 336.18 m/s measured in the air environment. The results in this study can be applied to theoretical and experimental studies of future Mars probes pertaining to ultrasonic positioning and detection.

Tibial speed of sound changes in preterm infants during the first year of life.

Metabolic bone disease of prematurity (MBD) frequently affects preterm infants. The accurate diagnosis of the MBD remains a challenging issue despite characteristic clinical, laboratory and imaging features. Recently, non-invasive quantitative ultrasound (QUS) measuring speed of sound (SOS) has been applied to assess bone status. Limited data are available on comparison of QUS among preterm infants. To evaluate development of tibial bone SOS values in preterm infants during the first year of life and compare the SOS values among different birth weight categories. QUS was used in 153 infants below 34 weeks of gestation. The study group was divided into 3 subgroups based on birth weight (BW): ≤1000 g, 1001-1500 g and >1500 g. SOS measurement was performed at 6 and 12 months of corrected age (CA). Overall, we found significant increase in mean tibial SOS between 6 and 12 months of CA (3004 ± 123 vs 3253 ± 109 m/s, p = 0.001). There were significant differences in SOS among birth weight categories at 6 months of CA (p = 0.045). However, these differences were not statistically significant at 12 months of CA (p = 0.289). The infants ≤ 1000 g scored the highest SOS values at both time points. Tibial SOS significantly increases during infancy in preterm newborns. Significant variation exists in SOS at 6 months, but not at 12 months of corrected age according to BW. Moreover, inverse correlation between BW and SOS indicating better bone status was revealed in extremely low birth weight infants at both 6 or at 12 months of CA.