Ultrasonic Application Research Articles

Acoustic transmission line based modelling of microscaled channels and enclosures.

An analytical model is presented that describes the acoustical impedance of cylindrical tubes and concentrically connected systems of such tubes valid up to the ultrasonic application. This allows the evaluation of microsized geometries encountered in acoustical microdevices, such as housing enclosures and sound port Helmholtz resonators. Each tube is treated as an acoustic transmission line (TL). Connected tubes are described using a coupling impedance, which accounts for viscous and inertial effects due to duct size changes. The acoustic TL model is directly derived from Navier-Stokes and energy equation, including frequency dependent boundary layer effects of the viscous and thermal dissipation. The results for various evaluated enclosure and resonator geometries are in good agreement with finite element method (FEM) simulation in both audio and ultrasonic frequency range and are compared to dedicated lumped element models referenced in literature. The presented model provides benefits in three ways: it is faster than FEM simulation and allows an implementation into analytical models and circuit simulation tools. Finally, it allows geometries with characteristic dimensions close to and above the wavelength to be treated with high precision in contrast to lumped element models.

Effect of ultrasound on bubble-particle interaction in quartz-amine flotation system

In this study, the effect of ultrasound (US) on the quartz-amine flotation system was investigated in detail by considering various surface chemistry techniques. The effect of ultrasound on particle size, shape factor, and surface roughness were characterized by using Brunauer-Emmett-Teller (BET) surface area measurements and scanning electron microscopy (SEM) analyses. The contact angle and bubble-particle attachment time, as well as adsorption density measurements was carried out to evaluate the effect of ultrasound on quartz surface wetting ability. In addition, atomic force microscopy (AFM) analyses were conducted, and finally micro-flotation studies were performed. As a result, it was found that the micro-flotation recovery at 2 × 10−5 M dodecyl amine hydrochloride (DAH) concentration increased from 45.45% to 63.64% with 30 W ultrasonic application at conditioning step. However, the micro-flotation recovery decreased to 37.50% when the ultrasonic power increased to 150 W. The results showed some effect of ultrasound on particle size, particle shape, and surface roughness in some extent. The increase in the contact angle and the decrease in the bubble-particle attachment time were observed. A slightly high adsorption density was measured. All these show a positive effect of ultrasound on quartz flotation with amine as a collector.

Accelerated mild heating of dry-cured ham by applying power ultrasound in a liquid medium

Mild thermal treatments could be considered a feasible technique with which to improve the texture of dry-cured ham. This study explores the feasibility of using power ultrasound (PuS) to intensify heat transfer during the mild thermal treatment of dry-cured ham immersed in a liquid medium. For that purpose, a temperature controlled ultrasonic bath was used to avoid the water temperature rise due to cavitation during ultrasonic application, which could mask the actual effect of ultrasound in heat transport mechanisms. Experiments were carried out using dry-cured ham slices (thickness 2 cm), which were heated at different temperatures (40, 45, 50 °C) with (PuS) and without (conventional mechanical stirring, CV) ultrasonic assistance. Temperature was monitored in the two main muscles of the ham (Biceps femoris and Semimembranosus) and in different positions of the slice. A model that considered heat transfer entirely controlled by conduction was chosen for describing heating kinetics and quantify the influence of temperature and ultrasonic application in the apparent thermal diffusivity. The heat conduction model proposed was adequate to describe both CV and PuS heating kinetics (VAR > 98.6%). Ultrasound application sped up the heat transfer by increasing the apparent thermal diffusivity up to 51%, but the higher the temperature, the lower the ultrasonic intensification. The apparent thermal diffusivities identified for the slices were satisfactorily validated (VAR > 98.4%) in independent experiments with ham cylinders. Therefore, PuS could be considered as an effective technology for the purposes of accelerating the heat transfer, thus shortening the heating time of dry-cured ham slices immersed in a liquid medium.

Broadband ultrasound-trapping barrier based on hollow cylinder with a periodic grating

It is important to modulate ultrasonic waves in some ultrasonic application fields. We formed an ultrasound-trapping barrier through a hollow cylinder with a periodic grating on the surface and simulated the barrier using the finite element method. Using the Schlieren imaging technique, we visualized the ultrasound field distribution in the structure. Both the experimental and simulation results revealed that the structure can work in a broadband frequency range, demonstrating the effectiveness and practicability of the structure as a virtual ultrasound barrier. We also describe how the silent region and the ultrasound intensity can be adjusted in the hollow cylinder.

The effect of cellulase, microwave and ultrasonic methods on crude polysaccharides extraction from the spore of Vietnamese lingzhi (Ganoderma lucidum)

Ganoderma lucidum known as reishi in Japanese and lingzhi in Chinese, are commonly used in Vietnam with excellent beneficial health effects. Polysaccharides are usually considered as their main active components. In this study, the polysaccharides from the spore of Vietnamese lingzhi, collected from the south of Vietnam, were analyzed and compared based on monitoring the absorbance of the samples in 490 nm, as well as enzymatic, microwave and ultrasonic methods with different surveyed parameters, such as: concentration of cellulase, microwave frequencies, extraction time, extraction temperature, ratio of sample and water. The results showed that the highest crude polysaccharide was extracted when using cellulase in enzymatic method with the following variables for the best adequate extraction conditions: cellulase concentration of 2.3%, enzyme treatment time of 150 min. and treatment temperature of 50°C. The highest amount of extracted polysaccharide was 7,1971% when the complex method was applied with preheating, enzyme use, ultrasonic application and microwave treatment, respectively.

Modelling and Optimization for Cutting Forces in Ultrasonic-Assisted Drilling of Soda Glass

Ultrasonic-Assisted Drilling (UAD) is a promising technology used for machining difficult-to-cut materials. In this work, an experimental investigation and statistical analysis are used to study the characteristics UAD and conventional drilling (CD) of soda glass using diamond abrasive tools. Statistically designed experiments were conducted using cutting fluid at different levels of tool feed rate, spindle speed, and tool abrasive-concentration. The mean thrust force and moment were considered the main responses. The significant drilling factors and their interactions were identified by modelling the process parameters and the output responses. The statistical models and optimum levels are determined. The ultrasonic application showed a significant effect on reducing the feed forces and drilling moment. Spindle speed is significant factor on thrust force and moment. The models error is less that 9%.

Effects of Ultrasonic Waves During Waterflooding for Enhanced Oil Recovery

Ultrasonic waves is an unconventional enhanced oil recovery (EOR) technology and has been a point of interest as it is more economical and environmentally friendly. Numerous research works on ultrasonic waves application in EOR have been reported, nevertheless the studies on the effect of ultrasonic waves towards oil mobilization in porous media are still debatable. Therefore, this study aims to investigate the effect of ultrasonic waves on enhanced oil recovery of three types of oil (kerosene, engine oil and crude oil) and a brine sample at different temperatures (27°C, 35°C, 45°C, 55°C). A series of ultrasonic waterflooding experiments were conducted under controlled temperature conditions. Results demonstrated that oil recovery increases as the temperature increases during ultrasonic exposure compared to conventional waterflooding. The ultrasonic waves creates energy that increase the mobility of a displacing fluid thus reduce the viscosity of displaced fluids whereas the vibration energy produced from ultrasonic waves induced the mobility of the entrapped oil within the pores. The IR Spectra test indicates that the oil produced from ultrasonic simulated waterflooding for oils with different viscosity and density from the IR Spectra result without ultrasonic exposure due to the influence of flow behavior and sweep efficiencies of fluids. As conclusion, the ultrasonic cavitation is one of mechanism that could improve oil mobilization and enhanced oil recovery.

Treatment of calvarial defects by resorbable and non-resorbable sonic activated polymer pins and mouldable titanium mesh in two dogs: a case report

BackgroundTo date, calvarial defects in dogs have traditionally been addressed with different types of implants including bone allograft, polymethylmethacrylate and titanium mesh secured with conventional metallic fixation methods. This report describes the use of an absorbable and non absorbable novel polymer fixation method, Bonewelding® technology, in combination with titanium mesh for the repair of calvarial defects in two dogs. The clinical outcomes and comparative complication using resorbable and non-resorbable thermoplastic pins were compared.Case presentationThis report of two cases documents the repair of a traumatic calvarial fracture in an adult male Greyhound and a cranioplasty following frontal bone tumor resection in an adult female Cavalier King Charles Spaniel with the use of a commercially available titanium mesh secured with an innovative thermoplastic polymer screw system (Bonewelding®). The treatment combination aimed to restore cranial structure, sinus integrity and cosmetic appearance. A mouldable titanium mesh was cut to fit the bone defect of the frontal bone and secured with either resorbable or non-resorbable polymer pins using Bonewelding® technology. Gentamycin-impregnated collagen sponge was used intraoperatively to assist with sealing of the frontal sinuses. Calvarial fracture and post-operative implant positioning were advised using computed tomography. A satisfactory restoration of skull integrity and cosmetic result was achieved, and long term clinical outcome was deemed clinically adequate with good patient quality of life. Postoperative complications including rostral mesh uplift with minor associated clinical signs were encountered when resorbable pins were used. No postoperative complications were experienced in non-resorbable pins at 7 months follow-up, by contrast mesh uplift was noted 3 weeks post-procedure in the case treated using absorbable pins.ConclusionsThe report demonstrates the innovative use of sonic-activated polymer pins (Bonewelding® technology) alongside titanium mesh is a suitable alternative technique for skull defect repair in dogs. The use of Bonewelding® may offer advantages in reduction of surgical time. Further, ultrasonic pin application may be less invasive than alternative metallic fixation and potentially reduces bone trauma. Polymer systems may offer enhanced mesh-bone integration when compared to traditional metallic implants. The use of polymer pins demonstrates initial potential as a fixation method in cranioplasty. Initial findings in a single case comparison indicate a possible advantage in the use of non-absorbable over the absorbable systems to circumvent complications associated with variable polymer degradation, further long term studies with higher patient numbers are required before reliable conclusions can be made.

CaBi4Ti4O15-based lead-free sol–gel composites for high-temperature application

CaBi4Ti4O15 (CBiT)-based lead-free sol–gel composites were developed for high-temperature ultrasonic transducer application. In this study, two types of lead-free sol–gel solution, Ba0.7Sr0.3TiO3 (BST) and Bi4Ti3O12 (BiT), were used for consistency to fabricate ∼50-µm-thick CBiT/BST and CBiT/BiT films on 3-mm-thick titanium substrates by a sol–gel spray technique. BST and BiT were chosen because of their high dielectric constant and high Curie temperature, respectively, in addition to their being lead-free materials. A thermal cycle test was carried out between RT and 600 °C, and clear multiple echoes were confirmed during three thermal cycles for both materials. In addition, the sensitivity of CBiT/BiT was higher than that of CBiT/BST although a higher poling temperature is required for CBiT/BiT. Therefore, an ultrasonic transducer potential for high-temperature application was successfully demonstrated.

In-process non-destructive ultrasonic testing application during wire plus arc additive manufacturing

In-process non-destructive ultrasonic testing application during wire plus arc additive manufacturing

Повышение точности отверстий при развертывании в деталях из труднообрабатываемых материалов

The investigation results of the tool geometry impact upon accuracy of holes worked in hard-to-machine parts at the ultrasonic oscillation introduction in a cutting area are shown. The processes of hole reaming in parts made of stainless steel and titanium alloys at ultrasonic oscillation application upon a tool are considered. Tool basic parameters defining the accuracy of holes obtained are defined. The regularities of the impact of face and back angles of reamer cutting ends, an angle of an intake cone and a tool spiral direction upon a hole smash are revealed.

Study on synergistic toughening of polypropylene with high-density polyethylene and elastomer-olefin block copolymers under ultrasonic application

In this study, we prepared the blends of polypropylene (PP) and high-density polyethylene (HDPE) with elastomer-olefin block copolymers (OBC) using an ultrasonic twin-screw extruder and investigated the mechanical, thermodynamic, and rheological properties of the blends. We examined the interfacial interactions among PP, OBC, and HDPE and observed that the PP/OBC/HDPE blends formed a core-shell structure with HDPE as the core and OBC as the shell. The crystallization temperature as well as the crystallinity of the blends were improved thanks to the heterogeneous nucleation between PP- and OBC-covered HDPE particles. Moreover, the impact strength of PP/OBC/HDPE blends was increased by three times as compared with PP because of the addition of 10 phr OBC and 15 phr HDPE; however, the viscosity increased slightly. Furthermore, it was evident from the fracture surface morphologies of PP/OBC/HDPE blends that the OBC-covered HDPE particles became smaller under the application of ultrasonic irradiation; hence, the interfacial interactions between the particles and the PP matrix were enhanced and the impact strength of the blends was improved.

A non-destructive testing methodology for damage assessment of reinforced concrete buildings after seismic events

In the present study non-destructive testing (NDT) methods involving ultrasonic and sonic wave propagation in the solid matter were applied in order to detect and investigate the modifications induced by the seismic load on reinforced concrete (RC) buildings. In particular, the aim of this experimental work was to delineate a methodology for quick and easy application on-the-field to provide information on the state of health of a RC structure subjected to a seismic event by investigating the columns in lower stories, which are generally more safely reachable for inspection. The methodology was experimented through shaking table tests reproducing several earthquakes. Shaking table tests were performed at ENEA Casaccia Research Centre on a full-scale 2-storey RC frame building designed under the current Italian code (NTC2008). Among the considered NDT techniques, direct and indirect sonic methods, as well as partial and complete approaches for ultrasonic tomography application were explored. The above NDTs were applied to the specimen before and after the shaking table testing. Numerical simulations by finite element methods (FEMs) were also adopted for a better comprehension of the dynamic behaviour of the specimen and interpretation of the experimental results. Through the comparison with typical damage indicators formulated for RC buildings, derived from the modal parameters evolution and from the displacements of the structure during the seismic load, promising indications were obtained and the proposed NDT-based methodology was discussed.

Dispersion of graphene nanoplatelets reinforcing type II cement paste

One of the most recent, affordable and at the same time cutting-edge class of carbon nanostructures are the graphene nanoplatelets (GnPs). They depict multifunctional capabilities such as improved mechanical properties in conjunction with high electrical and thermal conductivity making them suitable for the development of multifunctional materials. One of the most essential parameters, to successfully exploit the GnPs characteristics, is their homogeneous distribution inside the matrix. In this direction, the applicability of a method, similar to the one applied for the preparation of carbon nanofiber and carbon nanotube reinforced Type I cement nanocomposites, is here investigated. Ultrasonic processing and treatment with a 3rd generation superplasticizer was used to uniformly disperse the GnPs (of lateral size equal to 8 μm) in the mixing water. This admixture was exploited as a GnPs dispersing agent, as it is commonly used, to improve the workability of cementitious materials and is fully compatible with the matrix. The nanocomposites were prepared using Type II cement. The electrical resistivity of the nanocomposites developed was evaluated. Three-point bending tests were performed at prismatic beam specimens with an artificial notch at the age of 28 days. Both the effects of dispersing agent (superplasticizer) concentration and ultrasonication energy application were investigated. It was concluded that both the admixture concentration and ultrasonic energy application strongly affect the GnPs dispersion and reinforcing efficiency.

Control of cystic artery during laparoscopic cholecystectomy: clips versus ultrasonic energy devices which is better?

Background: This study was undertaken to know whether clip usage or ultrasonic energy application, obtains better haemostasis of cystic artery during laparoscopic cholecystectomy.Methods: About 80 patients undergoing laparoscopic cholecystectomy were selected on a prospective basis and divided into two equal groups- A and B. a comparative study was done between the two group. Clips were used to control cystic artery in group A patients and ultrasonic energy device was used for the same in group B.Results: In group A, 2 patients had clip slippage intraoperatively which was dealt by reapplication of clips.in group B,1 patient had intraoperative bleeding from cystic artery few minutes after application of ultrasonic energy which was dealt by bipolar cauterization. In both the groups no, postoperative bleeding was encountered.Conclusions: During laparoscopic cholecystectomy, clip usage and ultrasonic energy application are equally competent in achieving haemostasis of cystic artery.

Ultrasound-assisted extraction from defatted oat (Avena sativa L.) bran to simultaneously enhance phenolic compounds and β-glucan contents: Compositional and kinetic studies

In this research, the influence of ultrasonic application and temperature on extraction yields of free, esterified, bound phenolics, and β-glucan from defatted oat bran was investigated. Ultrasonic-assisted extraction (UAE) and conventional extraction (CE) were performed at different temperature. Extracts kinetics were monitored by determining the total phenolic content (TPC), antioxidant capacity (ORAC), and total avenanthramides of free phenolic compounds by mathematical model. HPLC-DAD was used to identify and quantify the main phenolic compounds. The results suggested that phenolic extraction yields of UAE was faster and higher than that of CE for free phenolics, with fitting to mathematically model (MRPD < 6%) well, whereas the bound fractions decreased. Besides, the TPC, ORAC and total avenanthramides of free phenolics were significantly improved by increasing the temperature in both UAE and CE, whereas the bound were significantly decreased. β-Glucan yields pretreated in UAE were approximately 37% higher than that in CE.

Structural Phase Evolution in Ultrasonic-Assisted Friction Stir Welded 2195 Aluminum Alloy Joints

The authors examined the structural and phase state of fixed joints produced by method of friction stir welding (FSW) and ultrasonic-assisted friction stir welding (UAFSW) from extruded profile of aluminum alloy AA2195. In order to identify the role of ultrasonic application in the course of welding, such characteristics, as volume fraction and average size of secondary particles are compared in the base material and stir zones of FSW and UAFSW joints. By applying the methods of SEM and TEM analysis, researchers established the complex character of phase transitions as a result of ultrasonic application.

Ultrasonic fog application of organic acids delays postharvest decay in red bayberry

Red bayberry (Morella rubra Lour.) has attractive fruit with appealing flavour and global market potential. However, its fresh fruit are highly susceptible to mechanical damage and postharvest fungal decay. The objective of the current study was to assess the efficacy of weak organic acids in delaying decay when applied to the fruit as an ultrasonic fog. Preliminary screening identified genotypes with acceptable postharvest longevity for use in the experiments. Fruit of genotype N1MR06 that received a 1h ultrasonic fog treatment with acetic acid exhibited a significantly (P<0.05) lower decay incidence of 18% after 10 d at 5°C as compared with 70% for untreated control fruit. However, the decay incidence in fruit treated with citric acid (55%) did not significantly (P>0.05) differ from the control. Subsequent experiments using fruit of genotypes N1MR06 and N1MR09 confirmed that ultrasonic fogging with acetic acid was an effective measure for delaying postharvest decay in red bayberry. Sensory evaluation along with total soluble solids and titratable acidity measurements showed that the acetic acid treatment had no adverse effect on the organoleptic quality of red bayberry. Overall, the study determined that genotype selection has an impact on red bayberry shelf life and that further shelf life gains can be achieved through ultrasonic fogging of safe, natural and inexpensive acetic acid.

Interactions at the planar Ag3Sn/liquid Sn interface under ultrasonic irradiation

The interactions at the interface between planar Ag3Sn and liquid Sn under ultrasonic irradiation were investigated. An intensive thermal grooving process occurred at Ag3Sn grain boundaries due to ultrasonic effects. Without ultrasonic application, planar shape of Ag3Sn layer gradually evolved into scalloped morphology after the solid-state Sn melting, due to a preferential dissolution of the intermetallic compounds from the regions at grain boundaries, which left behind the grooves embedding in the Ag3Sn layer. Under the effect of ultrasonic, stable grooves could be rapidly generated within an extremely short time (<10s) that was far less than the traditional soldering process (>10min). In addition, the deepened grooves leaded to the formation of necks at the roots of Ag3Sn grains, and further resulted in the strong detachment of intermetallic grains from the substrate. The intensive thermal grooving could promote the growth of Ag3Sn grains in the vertical direction but restrain their coarsening in the horizontal direction, consequently, an elongated morphology was presented. All these phenomena could be attributed to the acoustic cavitation and streaming effects of ultrasonic vibration.

Piezoelectric properties of PCW-PNN-PZT ceramics sintered at low temperature

ABSTRACTIn this study, in order to develop the composition ceramics for ultrasonic sensor application, Pb0.985Bi0.01(Co1/2W1/2)0.03(Ni1/3Nb2/3)0.09(ZrxTi1-x)0.88O3+0.25wt% CuO (abbreviated as PCW-PNN-PZT) system ceramics were prepared with the variations of x and then their phase microstructure, piezoelectric and dielectric characteristics were investigated with the variations of x. The compositions near the morphotropic phase boundary (MPB) appeared when x = 0.495. Moreover, the PCW-PNN-PZT ceramics could be sintered at low temperature of 920°C by adding sintering aids CuO. At sintering temperature of 920°C and x = 0.495 specimen, the density (ρ), electromechanical coupling factor(kp), dielectric constant (ϵr), mechanical quality (Qm) and piezoelectric constant (d33) piezoelectric figure of merit (d33·g33) indicated the optimal value of 7.94 g/cm3. 0.65, 1959, 356, 486 pC/N, and 15.56 [pm2/N], respectively, suitable for ultrasonic sensor application. The CuO was proved to lower the sintering temperature of piezoelectric ceramics due to the effects of PbO and CuO liquid phase.