WorldWideScience

Sample records for angle-dependent ultrasonic detection

  1. Ultrasonic flaw detection device in nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Yoshishige; Takabayashi, Jun-ichi

    1996-02-02

    Flaws on an outer circumferential surface of a shroud at inner side than jet pumps in a nuclear reactor are simply and reliably detected using ultrasonic waves. Ultrasonic waves are irradiated to the shroud which surrounds a reactor core at the inner side and has a plurality of jet pumps at the outer side at predetermined distances. An ultrasonic wave probe which detects flaws based on reflecting waves is suspended using a suspending rope. A jet nozzle is attached to a probe-attaching portion and water is jetted out to reactor water to move the probe-attaching portion in the reactor. Then, flaws can be detected easily and reliably using ultrasonic waves even at a narrow gap at the inner side of each jet pump. (N.H.).

  2. Ultrasonic flaw detection device in nuclear reactor

    International Nuclear Information System (INIS)

    Flaws on an outer circumferential surface of a shroud at inner side than jet pumps in a nuclear reactor are simply and reliably detected using ultrasonic waves. Ultrasonic waves are irradiated to the shroud which surrounds a reactor core at the inner side and has a plurality of jet pumps at the outer side at predetermined distances. An ultrasonic wave probe which detects flaws based on reflecting waves is suspended using a suspending rope. A jet nozzle is attached to a probe-attaching portion and water is jetted out to reactor water to move the probe-attaching portion in the reactor. Then, flaws can be detected easily and reliably using ultrasonic waves even at a narrow gap at the inner side of each jet pump. (N.H.)

  3. Research on ultrasonic detection of complex surfaces

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Parts of complex surface are widely used now in many fields, and their detection has caused much concern. In China many manufactories still carry on the traditional way of manual detection, which requires highly skilled personnel and efficiency is low. Some large manufactories have imported auto-detecting equipments, which require CAD data on the parts, or just divide the surface into several approximate planes for automatic detection. Phased-array system is seldom used, and the cost is high. Besides,most of the systems have not considered the automatic sensitivity compensation of parts with varying thickness. To improve the detection quality and efficiency of nondestructive test (NDT) of parts of complex surface, this paper puts forward an integrated ultrasonic NDT system characterized by: (1) Use of ultrasonic measurement and reverse of curved surface to solve the CAD data problem; (2) Use of an automatic sensitivity compensation algorithm (based on the part's modelling information obtained in surface reverse) to fit the variety of the thickness; (3) Use of template matching and pseudo-color imaging to improve the quality of detection results. The system features integration of low cost mature technologies, and is suitable for detection of various parts of different complex surfaces in medium-and-small enterprises. The test results showed that the system can automatically detect parts of complex surface successfully, and that the inspection result is good and reliable.

  4. Development of capacitive micromachined ultrasonic transducer for noncontact ultrasonic detection

    International Nuclear Information System (INIS)

    In this study, the capacitive micromachined ultrasonic transducer (cMUT) was developed. Theoretical analysis and finite element analysis of the behavior of membrane (such as resonance frequency, membrane deflection, collapse deflection and collapse voltage) of the cMUT were performed. The design parameters of the cMUT were estimated and are the dimension and thickness of membrane, thickness of sacrificial layer, thickness and size of electrode, size of active element and so on. With the micro-fabrication process, the cMUT was fabricated on the silicon wafer. To measure the membrane displacement of cMUT, the Michelson phase modulation fiber interferometer was constructed. The measured membrane displacement was good agreed with the result of finite element analysis. To estimate the ultrasonic wave generated by the cMUT, the ultrasonic transceiver system was constructed. The developed cMUT shows a good performance and hence will be widely used to the filed of non-contact ultrasonic application.

  5. Crack depth profiling using guided wave angle dependent reflectivity

    International Nuclear Information System (INIS)

    Tomographic corrosion monitoring techniques have been developed, using two rings of sensors around the circumference of a pipe. This technique is capable of providing a detailed wall thickness map, however this might not be the only type of structural damage. Therefore this concept is expanded to detect and size cracks and small corrosion defects like root corrosion. The expanded concept uses two arrays of guided-wave transducers, collecting both reflection and transmission data. The data is processed such that the angle-dependent reflectivity is obtained without using a baseline signal of a defect-free situation. The angle-dependent reflectivity is the input of an inversion scheme that calculates a crack depth profile. From this profile, the depth and length of the crack can be determined. Preliminary experiments show encouraging results. The depth sizing accuracy is in the order of 0.5 mm

  6. Detection of cystic structures using pulsed ultrasonically induced resonant cavitation

    Science.gov (United States)

    Bar-Cohen, Yoseph (Inventor); Kovach, John S. (Inventor)

    2002-01-01

    Apparatus and method for early detection of cystic structures indicative of ovarian and breast cancers uses ultrasonic wave energy at a unique resonance frequency for inducing cavitation in cystic fluid characteristic of cystic structures in the ovaries associated with ovarian cancer, and in cystic structures in the breast associated with breast cancer. Induced cavitation bubbles in the cystic fluid implode, creating implosion waves which are detected by ultrasonic receiving transducers attached to the abdomen of the patient. Triangulation of the ultrasonic receiving transducers enables the received signals to be processed and analyzed to identify the location and structure of the cyst.

  7. Detection of defects in tubes by ultrasonic techniques

    International Nuclear Information System (INIS)

    An ultrasonic technique is described for on-site detection of longitudinally extending defects in the heat exchange tubes of a sodium/water in-vessel heat exchanger. The method consists of directing ultrasonic beam energy along a chordal path into the inner wall surface of the tube to induce circumferentially extending shear waves in the wall and detecting the echo signals deflected from the defects. (U.K.)

  8. Application of Ultrasonic Technology in Detecting of Sludge Level

    Institute of Scientific and Technical Information of China (English)

    姚来凤; FENG Yi-hua; Kong Ling-ping

    2007-01-01

    The basic principle and the method of detecting the sludge level have been presented, and thé merits and demerits of different methods have been compared. The method of detecting by ultrasonic has been put forward based on characteristic and the need of measuring of sludge level.

  9. Non-contact feature detection using ultrasonic Lamb waves

    Science.gov (United States)

    Sinha, Dipen N.

    2011-06-28

    Apparatus and method for non-contact ultrasonic detection of features on or within the walls of hollow pipes are described. An air-coupled, high-power ultrasonic transducer for generating guided waves in the pipe wall, and a high-sensitivity, air-coupled transducer for detecting these waves, are disposed at a distance apart and at chosen angle with respect to the surface of the pipe, either inside of or outside of the pipe. Measurements may be made in reflection or transmission modes depending on the relative position of the transducers and the pipe. Data are taken by sweeping the frequency of the incident ultrasonic waves, using a tracking narrow-band filter to reduce detected noise, and transforming the frequency domain data into the time domain using fast Fourier transformation, if required.

  10. Ultrasonic flaw detecting device and ultrasonic probe for nozzle of pressure vessel

    International Nuclear Information System (INIS)

    The present invention improves the accuracy for flaw detecting test at a curved portion on the inner surface of a nozzle of a pressure vessel. Namely, a running vehicle runs around the outer surface of a nozzle of a pressure vessel. A support arm is loaded on the running vehicle being rotatably and extensively in the longitudinal direction. An ultrasonic wave probe is held at the top end of the support arm and detects flaws at the curved portion on the inner surface of the nozzle. The ultrasonic probe is made rotatable in a plane in perpendicular to the longitudinal direction of the support arm by way of a bearing. Further, the surface of the probe to be in contact with the outer surface as a surface to be inspected is chamfered at the four corners. With such a constitution, tightness of the ultrasonic probe to the surface to be detected is improved. As a result, the ultrasonic flaw detection for the curved portion at the inner circumference of the nozzle of the pressure vessel can be conducted at a high efficiency. (I.S.)

  11. Ultrasonic defect detection method for socket welding joint

    International Nuclear Information System (INIS)

    The present invention provides a method of detecting defects over a wide range of a socket weld portion of various kinds of pipelines used, for example, in a nuclear power plant. Namely, an inclined probe is disposed to a jig for detecting defects by ultrasonic waves. This is rotated at least by one turn along the peripheral surface of the material to be detected such as weld tube joints. Defects of weld portion of the material can be detected automatically by using ultrasonic waves during the rotation. The inclined probe for detecting defects by ultrasonic waves comprises a transmission portion having a planar transmittance oscillator disposed to a wedge on the transmission side and a receiving portion comprising a planar receiving oscillator disposed to a wedge on the receiving side. With such a constitution, ultrasonic waves are emitted from the transmission portion to the defect detection portion in the welded portion. If a defect is present, defective echo is reflected to the receiving portion disposed ahead of the probe. Since the defective echo changes depending on the height of the detective portion, the estimation of the height of the defect can be facilitated. (I.S.)

  12. Ultrasonic sensing of GMAW: Laser/EMAT defect detection system

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, N.M.; Johnson, J.A.; Larsen, E.D. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Van Clark, A. Jr.; Schaps, S.R.; Fortunko, C.M. [National Inst. of Standards and Technology, Boulder, CO (United States)

    1992-08-01

    In-process ultrasonic sensing of welding allows detection of weld defects in real time. A noncontacting ultrasonic system is being developed to operate in a production environment. The principal components are a pulsed laser for ultrasound generation and an electromagnetic acoustic transducer (EMAT) for ultrasound reception. A PC-based data acquisition system determines the quality of the weld on a pass-by-pass basis. The laser/EMAT system interrogates the area in the weld volume where defects are most likely to occur. This area of interest is identified by computer calculations on a pass-by-pass basis using weld planning information provided by the off-line programmer. The absence of a signal above the threshold level in the computer-calculated time interval indicates a disruption of the sound path by a defect. The ultrasonic sensor system then provides an input signal to the weld controller about the defect condition. 8 refs.

  13. Artificial intelligence and ultrasonic tests in detection of defects

    International Nuclear Information System (INIS)

    One of the most serious problems in the quality control of welded unions is the location, identification and classification of defects. As a solution to this problem, a technique for classification, applicable to welded unions done by electric arc welding as well as by friction, is proposed; it is based on ultrasonic signals. The neuronal networks proposed are Kohonen and Multilayer Percept ron, all in a virtual instrument environment. Currently the techniques most used in this field are: radiological analysis (X-rays) and ultrasonic analysis (ultrasonic waves). The X-ray technique in addition to being dangerous requires highly specialized personnel and equipment, therefore its use is restricted. The ultrasonic technique, in spite of being one of the most used for detection of discontinuities, requires personnel with wide experience in the interpretation of ultrasonic signals, this is a time-consuming process which necessarily increases its operation cost. The classification techniques that we propose turn out to be safe, reliable, inexpensive and easy to implement for the solution of this important problem. (Author) 8 refs

  14. A new ultrasonic signal amplification method for detection of bacteria

    International Nuclear Information System (INIS)

    A new method is presented that increases the sensitivity of ultrasound-based techniques for detection of bacteria. The technique was developed for the detection of catalase-positive microorganisms. It uses a bubble trapping medium containing hydrogen peroxide that is mixed with the sample for microbiological evaluation. The enzyme catalase is present in catalase-positive bacteria, which induces a rapid hydrolysis of hydrogen peroxide, forming bubbles which remain in the medium. This reaction results in the amplification of the mechanical changes that the microorganisms produce in the medium. The effect can be detected by means of ultrasonic wave amplitude continuous measurement since the bubbles increase the ultrasonic attenuation significantly. It is shown that microorganism concentrations of the order of 105 cells ml−1 can be detected using this method. This allows an improvement of three orders of magnitude in the ultrasonic detection threshold of microorganisms in conventional culture media, and is competitive with modern rapid microbiological methods. It can also be used for the characterization of the enzymatic activity. (paper)

  15. Development of Abnormality Detection System for Bathers using Ultrasonic Sensors

    Science.gov (United States)

    Ohnishi, Yosuke; Abe, Takehiko; Nambo, Hidetaka; Kimura, Haruhiko; Ogoshi, Yasuhiro

    This paper proposes an abnormality detection system for bather sitting in bathtub. Increasing number of in-bathtub drowning accidents in Japan draws attention. Behind this large number of bathing accidents, Japan's unique social and cultural background come surface. For majority of people in Japan, bathing serves purpose in deep warming up of body, relax and enjoyable time. Therefore it is the custom for the Japanese to soak in bathtub. However overexposure to hot water may cause dizziness or fainting, which is possible to cause in-bathtub drowning. For drowning prevention, the system detects bather's abnormal state using an ultrasonic sensor array. The array, which has many ultrasonic sensors, is installed on the ceiling of bathroom above bathtub. The abnormality detection system uses the following two methods: posture detection and behavior detection. The function of posture detection is to estimate the risk of drowning by monitoring bather's posture. Meanwhile, the function of behavior detection is to estimate the risk of drowning by monitoring bather's behavior. By using these methods, the system detects bathers' different state from normal. As a result of experiment with a subject in the bathtub, the system was possible to detect abnormal state using subject's posture and behavior. Therefore the system is useful for monitoring bather to prevent drowning in bathtub.

  16. Detection of laser generated ultrasonic wave using Michelson interferometer

    International Nuclear Information System (INIS)

    A stabilized Michelson Interferometer is proposed in order to detect the laser-generated ultrasonic waves in fee from the external noise such as low frequency mechanical vibration. In order to confirm the performance, theoretically expected waveforms were compared with experimentally detected ones in thermo-elastic region, where we generated ultrasonic wave in steel disk by using a Q-switched Nd:YAG laser. Also sound velocities of longitudinal and shear components were measured and they showed good agreement with the typical values in steel. Finally, the change of sound velocity according to the temperature change was measured to show that the proposed technique could be applied to the characterization of high temperature materials.

  17. Range-Angle-Dependent Beamforming by Frequency Diverse Array Antenna

    OpenAIRE

    Wen-Qin Wang; Huaizong Shao; Jingye Cai

    2012-01-01

    This paper proposes a range-angle-dependent beamforming for frequency diverse array (FDA) antenna systems. Unlike conventional phased-array antenna, the FDA antenna employs a small amount of frequency increment compared to the carrier frequency across the array elements. The use of frequency increment generates an antenna pattern that is a function of range, time and angle. The range-angle-dependent beamforming allows the FDA antenna to transmit energy over a desired range or angle. This prov...

  18. Arrival-Time Detection and Ultrasonic Flow-Meter Applications

    Science.gov (United States)

    Willatzen, Morten; Søndergaard, Peter; Latino, Carl; Voss, Frands; Lervad Andersen, Niels; Brokate, Martin; Bounaim, Aicha

    2006-11-01

    The Danfoss problem on ultrasonic flow measurement has been separated into three parts each handled by a subgroup of the authors listed above. The first subgroup deals with a presentation of modelling equations describing the physics of ultrasonic flow meters employing reciprocal ultrasonic transducer systems. The mathematical model presented allows the electrical output signal to be determined corresponding to any time-dependent electrical input signal. The transducers modelled consist of a piezoceramic material layer and a passive acoustic matching layer. The second subgroup analyzes the possibility of coding the input signal so as to simplify arrival-time detection by re.nding the coded input sequence in the received signal. The narrow-band nature of the transducers makes this problem non-trivial but suggestions for improvement are proposed. The analysis given is based on traditional autoand cross-correlation techniques. The third subgroup attempts to improve existing correlation methods in determining arrival-time detection of signals. A mathematical formulation of the problem is given and the application to a set of real signals provided by Danfoss A/S is performed with good results.

  19. Ultrasonic detection of cracks perpendicular to the surface

    International Nuclear Information System (INIS)

    An ultrasonic probe enabling cracks to be detected at significant depths is described. The underlying principle includes transformation of the longitudinal ultrasonic wave into a transverse wave. The probe is equipped with two transducers which are positioned on a common or separated refraction wedge. One transducer is so inclined that the longitudinal wave sent is incident under an angle which is smaller than the first critical angle. The other transducer receives the longitudinal wave refracted under an angle which is larger than the first critical angle. The small space required for the displacement of the probe on the surface tested is a major asset of this design. Angular probes with transformation of the longitudinal wave into a transverse wave will find particular use in in-service inspection of large nuclear reactor pressure vessels. (M.D.). 3 figs., 3 refs

  20. An Ultrasonic System for Weed Detection in Cereal Crops

    Directory of Open Access Journals (Sweden)

    Dionisio Andújar

    2012-12-01

    Full Text Available Site-specific weed management requires sensing of the actual weed infestation levels in agricultural fields to adapt the management accordingly. However, sophisticated sensor systems are not yet in wider practical use, since they are not easily available for the farmers and their handling as well as the management practice requires additional efforts. A new sensor-based weed detection method is presented in this paper and its applicability to cereal crops is evaluated. An ultrasonic distance sensor for the determination of plant heights was used for weed detection. It was hypothesised that the weed infested zones have a higher amount of biomass than non-infested areas and that this can be determined by plant height measurements. Ultrasonic distance measurements were taken in a winter wheat field infested by grass weeds and broad-leaved weeds. A total of 80 and 40 circular-shaped samples of different weed densities and compositions were assessed at two different dates. The sensor was pointed directly to the ground for height determination. In the following, weeds were counted and then removed from the sample locations. Grass weeds and broad-leaved weeds were separately removed. Differences between weed infested and weed-free measurements were determined. Dry-matter of weeds and crop was assessed and evaluated together with the sensor measurements. RGB images were taken prior and after weed removal to determine the coverage percentages of weeds and crop per sampling point. Image processing steps included EGI (excess green index computation and thresholding to separate plants and background. The relationship between ultrasonic readings and the corresponding coverage of the crop and weeds were assessed using multiple regression analysis. Results revealed a height difference between infested and non-infested sample locations. Density and biomass of weeds present in the sample influenced the ultrasonic readings. The possibilities of weed group

  1. Ultrasonic flaw detecting device for welded portion of stab and flaw detecting method therefor

    International Nuclear Information System (INIS)

    In the present invention, flaws are detected efficiently only for the welded portion of a stab disposed to a lower end plate of a pressure vessel used in a nuclear power plant. Namely, the device of the present invention comprises (1) an ultrasonic probe disposed to a shaft of the stab of control rod drives (CRD), (2) a shaft for supporting the ultrasonic probe, (3) a driving mechanism for circumferentially rotating and further axially moving the shaft, and (4) a controlling device for controlling the equipments described above and processing data. The position of the supersonic probe is moved vertically in the axial direction while rotating the shaft and rotating the supersonic probe in the circumferential direction by the driving mechanism driven upon receiving signals from the controlling device. Flaws can be detected only for the welded portion of the CRD stab using the ultrasonic probe by repeating the operation. In addition, efficiency for the flaw detecting operation is improved. (I.S.)

  2. Automatic ultrasonic image analysis method for defect detection

    International Nuclear Information System (INIS)

    Ultrasonic examination of austenitic steel weld seams raises well known problems of interpreting signals perturbed by this type of material. The JUKEBOX ultrasonic imaging system developed at the Cadarache Nuclear Research Center provides a major improvement in the general area of defect localization and characterization, based on processing overall images obtained by (X, Y) scanning. (X, time) images are formed by juxtaposing input signals. A series of parallel images shifted on the Y-axis is also available. The authors present a novel defect detection method based on analysing the timeline positions of the maxima and minima recorded on (X, time) images. This position is statistically stable when a defect is encountered, and is random enough under spurious noise conditions to constitute a discriminating parameter. The investigation involves calculating the trace variance: this parameters is then taken into account for detection purposes. Correlation with parallel images enhances detection reliability. A significant increase in the signal-to-noise ratio during tests on artificial defects is shown

  3. Concrete deterioration: detection by ultrasonic pulse velocity method

    International Nuclear Information System (INIS)

    Tests were performed to evaluate the feasibility of using Ultrasonic Pulse Velocity Method (UPVM) in detecting defect and determining its depth during the early age concrete. Five reinforced concrete (RC) slabs of grade 30, 40 and 50 specimens at day 3, 7,14 and 28 with a fabricated void at a known location were used. The results obtained were compared to determine the accuracy of the method hence the effectiveness of the method with different strength and as the concrete matures. This method detects defects in specimens during the early age The accuracy varies with concrete strength and as the concrete mature. The test results indicate the method can be used to assess the in-situ properties of concrete or for quality control on site. The method showed better accuracy with stronger concrete detects defects with the accuracy ranging from 55.75-99.62% from day 3-28 (full strength) respectively. (author)

  4. Theoretical and experimental investigation of fiber Bragg gratings with different lengths for ultrasonic detection

    Science.gov (United States)

    Yu, Zhouzhou; Jiang, Qi; Zhang, Hao; Wang, Junjie

    2016-06-01

    In this paper, the response of fiber Bragg gratings (FBGs) subjected to the ultrasonic wave has been theoretically and experimentally investigated. Although FBG sensors have been widely used in the ultrasonic detection for practical structural health monitoring, the relationship between the grating length and ultrasonic frequency is not yet to be obtained. To address this problem, an ultrasound detection system based on FBGs is designed and the response sensitivity of different lengths gratings are detected. Experimental results indicate that the grating with 3 mm length has a higher sensitivity when detecting high frequency ultrasonic wave, and the amplitude can be up to 0.6 mV. The 10 mm length grating has better detection sensitivity for low frequency ultrasonic wave and the amplitude is 0.8 mV. The results of this analysis provide useful tools for high sensitivity ultrasound detection in damage detection systems.

  5. Ultrasonic Techniques for Baseline-Free Damage Detection in Structures

    Science.gov (United States)

    Dutta, Debaditya

    This research presents ultrasonic techniques for baseline-free damage detection in structures in the context of structural health monitoring (SHM). Conventional SHM methods compare signals obtained from the pristine condition of a structure (baseline signals) with those from the current state, and relate certain changes in the signal characteristics to damage. While this approach has been successful in the laboratory, there are certain drawbacks of depending on baseline signals in real field applications. Data from the pristine condition are not available for most existing structures. Even if they are available, operational and environmental variations tend to mask the effect of damage on the signal characteristics. Most important, baseline measurements may become meaningless while assessing the condition of a structure after an extreme event such as an earthquake or a hurricane. Such events may destroy the sensors themselves and require installation of new sensors at different locations on the structure. Baseline-free structural damage detection can broaden the scope of SHM in the scenarios described above. A detailed discussion on the philosophy of baseline-free damage detection is provided in Chapter 1. Following this discussion, the research questions are formulated. The organization of this document and the major contributions of this research are also listed in this chapter. Chapter 2 describes a fully automated baseline-free technique for notch and crack detection in plates using a collocated pair of piezoelectric wafer transducers for measuring ultrasonic signals. Signal component corresponding to the damage induced mode-converted Lamb waves is extracted by processing the originally measured ultrasonic signals. The damage index is computed as a function of this mode-converted Lamb wave signal component. An over-determined system of Lamb wave measurements is used to find a least-square estimate of the measurement errors. This error estimate serves as the

  6. Symmetry constraints for the emission angle dependence of HBT radii

    CERN Document Server

    Heinz, Ulrich W; Lisa, M A; Wiedemann, Urs Achim

    2002-01-01

    We discuss symmetry constraints on the azimuthal oscillations of two-particle correlation (Hanbury Brown--Twiss interferometry) radii for non-central collisions between equal spherical nuclei. We also propose a new method for correcting in a model-independent way the emission angle dependent correlation function for finite event plane resolution and angular binning effects.

  7. Cloak based on the angle dependent constitutive parameters tensors.

    Science.gov (United States)

    Gurvitz, Egor; Andronaki, Semen; Vozianova, Anna; Khodzitsky, Mikhail

    2015-10-01

    The transformation optics cloak was proposed for the medium with the angle dependent tensors of permittivity and permeability consisted of the right-handed and left-handed metamaterial media. The cloaking effect was numerically simulated using finite element method in the terahertz frequency range for different wave sources. The impact of cloaking medium thickness on the invisibility effect was demonstrated. PMID:26480088

  8. Ultrasonic defect detection and size approximation using thin annulus probes

    International Nuclear Information System (INIS)

    Concern has been generated recently about the capabilities of performing nondestructive evaluation (NDE) of the closure head penetrations in nuclear-reactor pressure vessels (PV). These penetrations, primarily for instrumentation and control rod drive mechanisms (CRDMs), are usually thick-walled Inconel tubes, shrink-fitted into the steel closure head. The penetrations are then welded between the outside surface of the penetration and inside surface of the closure head. Stress corrosion cracks initiating at the inner surface of the penetration have been reported at several plants. Through wall cracks in the CRDM penetration or CRDM weld could lead to loss of PV coolant. The penetration presents a complex geometry for conventional NDE techniques. A thermal sleeve, through which pass the mechanical linkages for control-rod operation, is inserted into the penetration so that only a small annulus (nominally 3 mm) exists between the thermal sleeve and inside surface of the penetration. SwRI has developed and evaluated ultrasonic techniques for sizing defects in this area. Long, thin probes were designed to fit into the annulus to carry irrigated ultrasonic transducers into the region of interest. The probes were used to detect cracks in the penetration and to estimate remaining wall thickness

  9. ULTRASONIC DETECTION OF SURFACE-BREAKING RAILHEAD DEFECTS

    International Nuclear Information System (INIS)

    We recently presented measurements of defects on the railhead, using a novel pitch-catch ultrasonic system comprising of two electro-magnetic acoustic transducers (EMATs) generating and detecting Rayleigh waves. Current systems used on the UK rail network for detecting surface breaking defects are limited in speed (5 mm). The non-contact EMAT system has the potential to operate at higher line speed, improving network inspection coverage. The current system detects signals and performs an FFT in less than 1 ms, and changes in the detected signal amplitude and frequency content are used to characterise defects. A new set of simulated defects on sections of rail have been produced, including half-face slots machined normal to the railhead surface, clusters of angled slots, and pocket defects more typical of real defects. The smallest pocket defects are difficult to detect, with changes in signal amplitude and cut-off falling close to the noise level. However, at chosen higher frequencies a drop in FFT magnitude indicates the presence of a defect, and this indicator can be logically combined with amplitude and cut-off measurements to provide a more reliable result. Preparation for testing on a rotating rail rig at high speeds is ongoing

  10. XFEL OSCILLATOR SIMULATION INCLUDING ANGLE-DEPENDENT CRYSTAL REFLECTIVITY

    International Nuclear Information System (INIS)

    The oscillator package within the GINGER FEL simulation code has now been extended to include angle-dependent reflectivity properties of Bragg crystals. Previously, the package was modified to include frequencydependent reflectivity in order to model x-ray FEL oscillators from start-up from shot noise through to saturation. We present a summary of the algorithms used for modeling the crystal reflectivity and radiation propagation outside the undulator, discussing various numerical issues relevant to the domain of high Fresnel number and efficient Hankel transforms. We give some sample XFEL-O simulation results obtained with the angle-dependent reflectivity model, with particular attention directed to the longitudinal and transverse coherence of the radiation output.

  11. Ultrasonication of pyrogenic microorganisms improves the detection of pyrogens in the Mono Mac 6 assay

    DEFF Research Database (Denmark)

    Moesby, Lise; Hansen, E W; Christensen, J D

    2000-01-01

    aureus and Salmonella typhimurium, but neither Candida albicans nor Aspergillus niger. After ultrasonication of the microorganisms it is possible to detect C. albicans and A. niger. The interleukin-6 inducing ability of the examined microorganisms is in no case reduced after ultrasonic treatment. However...

  12. Influence on ultrasonic incident angle and defect detection sensitivity by cast stainless steel structure

    International Nuclear Information System (INIS)

    It is well known that ultrasonic waves are affected strongly by macro-structures in cast stainless steel, as in the primary pipe or other components in pressurized water reactors (PWRs). In this work, ultrasonic refractive angles and defect detection sensitivities are investigated at different incident angles to cast stainless steel. The aims of the investigation are to clarify the transmission of ultrasonic waves in cast stainless steel and to contribute to the transducer design. The results are that ultrasonic refractive angles in cast stainless steel shift towards the 45-degree direction with respect to the direction of dendritic structures by 11.8 degrees at the maximum and that the sensitivity of transducer for inner surface breaking cracks increases with decreasing incident angle. However, in an ultrasonic inspection of actual welds at smaller incident angles, a trade-off occurs between increased defect detection sensitivity and decreased defect discrimination capability due to intense false signals produced by non-defective features. (orig.)

  13. Extended incident-angle dependence formula of sputter yield

    International Nuclear Information System (INIS)

    We extend a new semi-empirical formula for incident-angle dependence of normalized sputter yield that includes the contribution to sputter yield from the direct knock-out process that was not considered in the previously proposed one. Three parameters included in the new one are estimated for data calculated with ACAT code for D+ ions incident obliquely on C, Fe and W materials in incident-energy regions from several tens of eV to 10 keV. Then, the parameters are expressed with functions of incident energy. The formula with the functions derived well reproduces that using the ACAT data in the whole energy range. (author)

  14. Angle dependence of Andreev scattering at semiconductor-superconductor interfaces

    DEFF Research Database (Denmark)

    Mortensen, Asger; Flensberg, Karsten; Jauho, Antti-Pekka

    1999-01-01

    We study the angle dependence of the Andreev scattering at a semiconductor-superconductor interface, generalizing the one-dimensional theory of Blonder, Tinkham, and Klapwijk (BTK),An increase of the momentum parallel to the interface leads to suppression of the probability of Andreev reflection ...... angle of incidence above which only normal reflection exists. For two- and three-dimensional interfaces a lower excess current compared to ballistic transport with perpendicular incidence is found. Thus, the one-dimensional BTK model overestimates the barrier strength for two- and three...

  15. Gamma mixture classifier for plaque detection in intravascular ultrasonic images.

    Science.gov (United States)

    Vegas-Sánchez-Ferrero, Gonzalo; Seabra, José; Rodriguez-Leor, Oriol; Serrano-Vida, Angel; Aja-Fernández, Santiago; Palencia, César; Martín-Fernández, Marcos; Sanches, Joao

    2014-01-01

    Carotid and coronary vascular incidents are mostly caused by vulnerable plaques. Detection and characterization of vulnerable plaques are important for early disease diagnosis and treatment. For this purpose, the echomorphology and composition have been studied. Several distributions have been used to describe ultrasonic data depending on tissues, acquisition conditions, and equipment. Among them, the Rayleigh distribution is a one-parameter model used to describe the raw envelope RF ultrasound signal for its simplicity, whereas the Nakagami distribution (a generalization of the Rayleigh distribution) is the two-parameter model which is commonly accepted. However, it fails to describe B-mode images or Cartesian interpolated or subsampled RF images because linear filtering changes the statistics of the signal. In this work, a gamma mixture model (GMM) is proposed to describe the subsampled/interpolated RF images and it is shown that the parameters and coefficients of the mixture are useful descriptors of speckle pattern for different types of plaque tissues. This new model outperforms recently proposed probabilistic and textural methods with respect to plaque description and characterization of echogenic contents. Classification results provide an overall accuracy of 86.56% for four classes and 95.16% for three classes. These results evidence the classifier usefulness for plaque characterization. Additionally, the classifier provides probability maps according to each tissue type, which can be displayed for inspecting local tissue composition, or used for automatic filtering and segmentation. PMID:24402895

  16. Advanced defect detection algorithm using clustering in ultrasonic NDE

    Science.gov (United States)

    Gongzhang, Rui; Gachagan, Anthony

    2016-02-01

    A range of materials used in industry exhibit scattering properties which limits ultrasonic NDE. Many algorithms have been proposed to enhance defect detection ability, such as the well-known Split Spectrum Processing (SSP) technique. Scattering noise usually cannot be fully removed and the remaining noise can be easily confused with real feature signals, hence becoming artefacts during the image interpretation stage. This paper presents an advanced algorithm to further reduce the influence of artefacts remaining in A-scan data after processing using a conventional defect detection algorithm. The raw A-scan data can be acquired from either traditional single transducer or phased array configurations. The proposed algorithm uses the concept of unsupervised machine learning to cluster segmental defect signals from pre-processed A-scans into different classes. The distinction and similarity between each class and the ensemble of randomly selected noise segments can be observed by applying a classification algorithm. Each class will then be labelled as `legitimate reflector' or `artefacts' based on this observation and the expected probability of defection (PoD) and probability of false alarm (PFA) determined. To facilitate data collection and validate the proposed algorithm, a 5MHz linear array transducer is used to collect A-scans from both austenitic steel and Inconel samples. Each pulse-echo A-scan is pre-processed using SSP and the subsequent application of the proposed clustering algorithm has provided an additional reduction to PFA while maintaining PoD for both samples compared with SSP results alone.

  17. Elevation angle dependence of the SMA antenna focus position

    CERN Document Server

    Matsushita, S; Sakamoto, K; Hunter, T R; Patel, N A; Sridharan, T K; Wilson, R W; Matsushita, Satoki; Saito, Masao; Sakamoto, Kazushi; Hunter, Todd R.; Patel, Nimesh A.; Sridharan, Tirupati K.; Wilson, Robert W.

    2006-01-01

    We report the measurement results and compensation of the antenna elevation angle dependences of the Sub-millimeter Array (SMA) antenna characteristics. Without optimizing the subreflector (focus) positions as a function of the antenna elevation angle, antenna beam patterns show lopsided sidelobes, and antenna efficiencies show degradations. The sidelobe level increases and the antenna efficiencies decrease about 1% and a few %, respectively, for every 10 degrees change in the elevation angle at the measured frequency of 237 GHz. We therefore obtained the optimized subreflector positions for X (azimuth), Y (elevation), and Z (radio optics) focus axes at various elevation angles for all the eight SMA antennas. The X axis position does not depend on the elevation angle. The Y and Z axes positions depend on the elevation angles, and are well fitted with a simple function for each axis with including a gravity term (cosine and sine of elevation, respectively). In the optimized subreflector positions, the antenna ...

  18. Angle-dependent vortex structure in a high anisotropy superconductor

    International Nuclear Information System (INIS)

    Angle-dependent muon spin rotation measurements have been made on the organic superconductor κ-(BEDT-TTF)2Cu(SCN)2. Oscillations are observed in the width of the internal field distribution, which are periodic in the perpendicular component of the applied magnetic field, Bz=B cos θ, with a uniform period over a range of angles and fields. These oscillations are superimposed on the standard cos θ scaling expected for the width in a highly anisotropic superconductor. The oscillation period is of order 2 mT and the amplitude is particularly strong at fields comparable with the period. The origin of this novel phenomenon is discussed in terms of the low field instabilities of tilted vortices in this highly anisotropic superconductor

  19. Detection of plating defects using ultrasonic and eddy current test methods

    International Nuclear Information System (INIS)

    The validity of ultrasonic and eddy current testing of austenitic platings of reactor pressure vessels was investigated in the context of a project funded by the Federal Radiation Protection Office (Bundesamt fuer Strahlenschutz). In the first phase, test specimens with natural defects were fabricated at MPA Stuttgart; in the second phase, plating defects were introduced in a MPA large-size vessel. Measurements showed that most plating defects will be detected by standard ultrasonic testing. The highest accuracy was achieved by a combination of ultrasonic and eddy current testing. (orig.)

  20. Decoupling of Getting Up Detection Device Using Ultrasonic Radar by Changing Duty Ratio of Transmission Wave

    Science.gov (United States)

    Yamada, Yo; Tanaka, Kanya; Haruyama, Kazuo; Wakasa, Yuji; Akashi, Takuya

    The decline in the quality of patient's safety control is a problem, because the number of caretakers is reduced by the acceleration of demographic aging in an elder care facility. Especially, the detection of getting up from the bed is very important for preventing patients from falling and wandering unbreakable. In our previous study, we have developed the getting up detection device with an ultrasonic radar, which is safe, cheap, and break-proof. However, if there are many patients in a ward, it is difficult to use some ultrasonic radars. The reason is that if some ultrasonic radars, which have the same frequency, are used in same ward, the ultrasonic signals are coherent with each other. To solve this problem, we propose a novel incoherent method. This method is achieved by improving the software in the device at a low cost.

  1. Further development of the ultrasonic testing method for improving the detection and analysis of corrosion cracks

    International Nuclear Information System (INIS)

    Defect detection and analysis can be improved applying the ultrasonic multifrequency technique basing on the principle that each defect type reveals two characteristic domains during ultrasonic testing, i.e. scattering and reflection. The frequency range ft, which is the frequency range where transition from scattering to reflection occurs, is a major characteristic value identifying the defect size, which in the case of corrosion cracks is directly proportional to the crack depth. (orig.)

  2. Damage detection in submerged plates using ultrasonic guided waves

    Indian Academy of Sciences (India)

    Sandeep Sharma; Abhijit Mukherjee

    2014-10-01

    This paper describes a non-contact and non-invasive health monitoring strategy for submerged plate structures using guided waves. The structure under consideration is immersed in water and subjected to longitudinal ultrasonic waves at specific angles of incidence using a cylindrical piezoelectric transducer using the surrounding water as coupling medium. Suitable ultrasonic guided wave modes with optimum scanning capabilities have been generated and identified in submerged plate system. Finally, the propagation of selected modes through submerged notched plates is investigated. Sensitivity of leaky waves to the notches has been studied. The methodology would help in identifying damages in the submerged plate structures.

  3. Hidden corrosion detection in aircraft aluminum structures using laser ultrasonics and wavelet transform signal analysis.

    Science.gov (United States)

    Silva, M Z; Gouyon, R; Lepoutre, F

    2003-06-01

    Preliminary results of hidden corrosion detection in aircraft aluminum structures using a noncontact laser based ultrasonic technique are presented. A short laser pulse focused to a line spot is used as a broadband source of ultrasonic guided waves in an aluminum 2024 sample cut from an aircraft structure and prepared with artificially corroded circular areas on its back surface. The out of plane surface displacements produced by the propagating ultrasonic waves were detected with a heterodyne Mach-Zehnder interferometer. Time-frequency analysis of the signals using a continuous wavelet transform allowed the identification of the generated Lamb modes by comparison with the calculated dispersion curves. The presence of back surface corrosion was detected by noting the loss of the S(1) mode near its cutoff frequency. This method is applicable to fast scanning inspection techniques and it is particularly suited for early corrosion detection. PMID:12782263

  4. Angle-dependent bandgap engineering in gated graphene superlattices

    Science.gov (United States)

    García-Cervantes, H.; Gaggero-Sager, L. M.; Sotolongo-Costa, O.; Naumis, G. G.; Rodríguez-Vargas, I.

    2016-03-01

    Graphene Superlattices (GSs) have attracted a lot of attention due to its peculiar properties as well as its possible technological implications. Among these characteristics we can mention: the extra Dirac points in the dispersion relation and the highly anisotropic propagation of the charge carriers. However, despite the intense research that is carried out in GSs, so far there is no report about the angular dependence of the Transmission Gap (TG) in GSs. Here, we report the dependence of TG as a function of the angle of the incident Dirac electrons in a rather simple Electrostatic GS (EGS). Our results show that the angular dependence of the TG is intricate, since for moderated angles the dependence is parabolic, while for large angles an exponential dependence is registered. We also find that the TG can be modulated from meV to eV, by changing the structural parameters of the GS. These characteristics open the possibility for an angle-dependent bandgap engineering in graphene.

  5. Ultrasonic Phased Array Techniques for Detection of Flaws of Stud Bolts in Nuclear Power Plants

    International Nuclear Information System (INIS)

    The reactor vessel body and closure head are fastened with the stud bolt that is one of crucial parts for safety of the reactor vessels in nuclear power plants. It is reported that the stud bolt is often experienced by fatigue cracks initiated at threads. Stud bolts are inspected by the ultrasonic technique during the overhaul periodically for the prevention of failure which leads to radioactive leakage from the nuclear reactor. The conventional ultrasonic inspection for stud bolts was mainly conducted by reflected echo method based on shadow effect. However, in this technique, there were numerous spurious signals reflected from every oblique surfaces of the thread. In this study, ultrasonic phased array technique was applied to investigate detectability of flaws in stud bolts and characteristics of ultrasonic images corresponding to different scanning methods, that is, sector and linear scan. For this purpose, simplified stud bolt specimens with artificial defects of various depths were prepared

  6. Ultrasonic detection technology based on joint robot on composite component with complex surface

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Juan; Xu, Chunguang; Zhang, Lan [School of Mechanical Engineering, Beijing Institute of Technology, Beijing (China)

    2014-02-18

    Some components have complex surface, such as the airplane wing and the shell of a pressure vessel etc. The quality of these components determines the reliability and safety of related equipment. Ultrasonic nondestructive detection is one of the main methods used for testing material defects at present. In order to improve the testing precision, the acoustic axis of the ultrasonic transducer should be consistent with the normal direction of the measured points. When we use joint robots, automatic ultrasonic scan along the component surface normal direction can be realized by motion trajectory planning and coordinate transformation etc. In order to express the defects accurately and truly, the robot position and the signal of the ultrasonic transducer should be synchronized.

  7. Ultrasonic flaw detection of the thin-walled articles weld joints

    International Nuclear Information System (INIS)

    Two versions of the weld joints ultrasonic flaw detections for thin-walled articles using computer-assisted flaw detector on display of which the color picture is formed are described. The detection method of weld joints flaws obtained at contact and diffusive welding is developed

  8. Ultrasonic temperature profiling system for detecting critical heat flux in non-uniformly heated tube bundles

    International Nuclear Information System (INIS)

    A new ultrasonic instrument system was developed and applied to the problem of detecting critical heat flux (CHF) in experiments that simulate a nuclear reactor fuel assembly. This instrumentation system used the principles of ultrasonic thermometry to detect and localte CHF in a tube bundle with non-uniform axial heat generation. The technique consists of measuring the time between pairs of ultrasonic echoes that reflect from a sequence of evenly spaced discontinuities along a sensor. Each measurement of time is directly related to the temperature of a specific segment of a sensor. The system was designed to handle many 16-zone sensors at a high rate of data acquisition so that CHF could be rapidly detected and accurately located. This paper includes a description of the sensor and the signal processing techniques as well as examples of the system's response to CHF

  9. Ultrasonic C-Scan Parameters for Detection of Hydride Blisters in Zirconium Pressure Tube

    International Nuclear Information System (INIS)

    EMAT Since Zr-2.5Nb pressure tubes have a high risk for the formation of blisters during their operation in pressurized heavy water reactors, there has been a strong incentive to develop a method for the non-destructive detection of blisters grown on the tube surfaces. However, because there is little mismatch in acoustic impedance between the hydride blisters and zirconium matrix, it is not easy to distinguish the boundary between the blister and zirconium matrix wit h the conventional methods. This study focused on the development of the ultrasonic method to detect the hydride blisters formed on Zr-2.5Nb pressure tubes. Hydride blisters were grown on the outer surface of the zirconium pressure tubes using a cold finger attached to steady state thermal diffusion equipment. An ultrasonic velocity ratio method as well as conventional ultrasonic parameters with immersion technique was developed to detect smaller hydride blisters on the zirconium pressure tube.

  10. Damage detection in acsr cables based on ultrasonic guided waves

    OpenAIRE

    Mijarez, Rito; Baltazar, Arturo; Rodríguez-Rodríguez, Joaquín; Ramírez-Niño, José

    2014-01-01

    The use of ultrasonic guided waves is growing as a non-destructive testing technique of multi-wire cables used in civil engineering structures. Wave propagation characteristics in these types of structures have been challenging to investigate owing to the load-dependent inter-wire contact and the helical geometry of the peripheral wires. In this work, experiments of guided waves propagated in a 0.9m Aluminum Conductor Steel Reinforced (ACSR) cable were conducted employing two longitudinal pie...

  11. Model based defect detection for free stator of ultrasonic motor

    DEFF Research Database (Denmark)

    Amini, Rouzbeh; Mojallali, Hamed; Izadi-Zamanabadi, Roozbeh;

    2007-01-01

    In this paper, measurements of admittance magnitude and phase are used to identify the complex values of equivalent circuit model for free stator of an ultrasonic motor. The model is used to evaluate the changes in the admittance and relative changes in the values of equivalent circuit elements. ....... This method identifies the damages and categorizes them. The validity of the method is verified by using free stator measurements of defect free stators of a recently developed multilayer piezoelectric motor....

  12. Enhancement of crack detection in stud bolts of nuclear reactor by ultrasonic technique

    International Nuclear Information System (INIS)

    The stud bolt is one of crucial parts for safety of reactor vessels in nuclear power plants. Crack initiation and propagation were reported in stud bolts using closure of reactor vessel and head. Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure and radioactive leakage from nuclear reactor. In conventional ultrasonic testing for inspection of stud bolts, crack was detected by using shadow effect. It takes too much time to inspect stud bolt by using conventional ultrasonic technique. In addition, there were numerous spurious signals reflected from every oblique surfaces of thread. In this study, the signal processing technique for enhancing conventional ultrasonic technique and the advanced ultrasonic phased array technique were introduced for inspect stud bolts. The signal processing technique provides removing spurious signal reflected from every oblique surfaces of thread and enhances detectability of defects. The phased array technique provides fast inspection and can be applied for structure of complex shape. There are sector scanning and linear scanning methods in phased array technique, and these scanning methods were applied to inspect stud bolt and detectability was investigated. (author)

  13. Inner wall inspection of steam generator tubes with circumferential welds using ultrasonic crack detection

    International Nuclear Information System (INIS)

    Cracks in the neighbourhood of circumferential welds at the inside of generator tubes to the weld seam can be detected with an ultrasonic probe system using Rayleigh's surface waves. A reference reflector with about 0.5 mm in depth and 1.5 mm in length is used. The ultrasonic inspection system is using a rotating mirror with two faces which can detect cracks on both sides of the weld and which can clearly separate crown or root indications from real defects. The signal-to-noise ratio is better than 12 dB. The system and results on tubes with artificial and real test reflectors are described

  14. Inner wall inspection of steam generator tubes with circumferential welds using ultrasonic crack detection

    International Nuclear Information System (INIS)

    Cracks in the neighbourhood of circumferential welds at the inside of generator tubes to the weld seam can be detected with an ultrasonic probe system using Rayleigh's surface waves. A reference reflector with about 0.5 mm in depth and 1.5 mm in length is used. The ultrasonic inspection system is using a rotating mirror with two faces which can detect cracks on both sides of the weld and which can clearly separate crown or root indications from real defects. The signal-to-noise ratio is better than 12 dB. The system and results on tubes with artificial and real test reflectors are described. 8 refs

  15. Generation and detection technique of laser-ultrasonic

    International Nuclear Information System (INIS)

    A number of physical processes may take place when a solid surface is illuminated by a pulse laser. At lower power region these include heating, the generation of thermal waves, elastic waves (ultrasound). At higher powers, material may be ablated from the surface and a plasma formed, while in the sample there may be melting, plastic deformation and even the formation of cracks. In this letter we consider the generation techniques of laser-ultrasonic il all possible state. And we consider the measurement technique of laser-generated ultrasound based on the optical method.

  16. A coupled elastoplastic-damage constitutive model with Lode angle dependent failure criterion

    OpenAIRE

    Erice Echávarri, Borja; Galvez Diaz-Rubio, Francisco

    2014-01-01

    A coupled elastoplastic-damage constitutive model with Lode angle dependent failure criterion for high strain and ballistic applications is presented. A Lode angle dependent function is added to the equivalent plastic strain to failure definition of the Johnson–Cook failure criterion. The weakening in the elastic law and in the Johnson–Cook-like constitutive relation implicitly introduces the Lode angle dependency in the elastoplastic behaviour. The material model is calibrated for precipitat...

  17. Automatic ultrasonic system for flaw detection and dimensional measurement of precision tubes

    International Nuclear Information System (INIS)

    This paper describes a system, which is installed at Nuclear Fuel Complex, Hyderabad. It is a tube rotation fixed probe type of system designed for fully automatic operation at high speed using immersion technique for ultrasonic flaw detection and dimensional measurement of precision of zirconium alloy seamless tubes used in fuel bundles for nuclear reactors

  18. Data Mining Rules for Ultrasonic B-Type Detection and Diagnosis for Cholecystolithiasis

    Institute of Scientific and Technical Information of China (English)

    LOUWei; YANLi-min; HEGuo-sen

    2004-01-01

    This paper presents realistic data mining based on the data of B-type ultrasonic detection and diagnosis for cholrcystolithiasis (gallbladder stone in biliary tract) recorded by a district central hospital in Shanghai during the past several years. Computer simulation and modeling is described.

  19. Defect Detection of Fiberglass Composite Laminates (FGCL) with Ultrasonic A-Scan Signal Measurement

    Science.gov (United States)

    Mahmod, M. F.; Abu Bakar, Elmi; Othman, A. R.

    2016-02-01

    Fiberglass composite laminates are widely used in many industries, due to its advantages of high specific strength and high specific modulus. Invisible defect such as delamination and inclusion may cause composite structural failure. Therefore, several research on ultrasonic testing for composite material defect detection have been done for the past few years. However, improper parameter setup may lead to significant error to determine the behavior of defects. In this paper, the intensive study on defect detection with ultrasonic single crystal immersion transducer has been conducted. In general, the defects detection thru acquired signal is determine the behavior of defects through the certain ultrasonic parameter setup such as sound velocity, pulse width, gain, sampling rate and transducer distance with specimen surface. Furthermore, an A-scan signal interpretation for FGCL defect detection is demonstrated and illustrated. This research is focusing on for FGCL with maximum thickness up to 10 mm in ambient temperature. The result shows an appropriate ultrasonic parameter will result better signal interpretation analysis.

  20. Detection of defect in concrete specimen using ultrasonic wave overlap method

    International Nuclear Information System (INIS)

    The detection of defects in concrete specimens using ultrasonic wave overlap method is studied. Experimental studies are performed to understand the interaction between crack depth, inclusion, and steel bar. In this study, the specimens with surface-opening crack and inclusion were made and tested. The scope of measurement is evaluated through the extension of probing distance. The relationship between crack depth and probing distance estimates that it is effect in case of probing distance less than crack depth. With the results from this study, it is found that the technique using the ultrasonic wave overlap is one of very useful method to evaluate the concrete defect.

  1. Detection of defect in concrete specimen using ultrasonic wave overlap method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeon Su; Rhim, Hong Chul [Yonsei University, Seoul (Korea, Republic of); Woo, Sang Kyun; Song, Young Chul [Korea Electric Power ResearchInstitue, Daejeon (Korea, Republic of)

    2001-11-15

    The detection of defects in concrete specimens using ultrasonic wave overlap method is studied. Experimental studies are performed to understand the interaction between crack depth, inclusion, and steel bar. In this study, the specimens with surface-opening crack and inclusion were made and tested. The scope of measurement is evaluated through the extension of probing distance. The relationship between crack depth and probing distance estimates that it is effect in case of probing distance less than crack depth. With the results from this study, it is found that the technique using the ultrasonic wave overlap is one of very useful method to evaluate the concrete defect.

  2. Development of the ultrasonic flaw detection system for prototype FBR 'Monju' steam generators

    International Nuclear Information System (INIS)

    The supersonic flaw detection system for steam generator tubes, which is required to inspect the tubes quickly and accurately and to confirm the soundness, was developed, and the synthetic test of the whole system was carried out for verifying the function. This system is characterized by testing the heating tubes from inside, inserting electronic scanning, multi-array type ultrasonic flow detection probes by water flow pressure, and has the function to simultaneously detect circumferential, axial and wall-thinning defects at 4 m/min in helical coil tubes of about 100 m length. Besides, as the flaw detection ability, the defects with depth equivalent to 5 % of the wall thickness of tubes (0.2 mm) can be detected. In the synthetic test of the whole system, the steam generator tubes with same dimensions as those for Monju were used, and the easiness of inserting the probes into the tubes and the ability of detecting flaws (with depth of 20 % wall thickness) were confirmed. This system consists of ultrasonic flaw detection probes, an ultrasonic flaw detection equipment, a signal processor and a cable driving and positioning device. The objective of the development of this system was almost attained. (Kako, I.)

  3. A study on the diagnosis for power transformer by Ultrasonic wave detection

    International Nuclear Information System (INIS)

    The objectives of this study is to develop a device which could diagnose periodically the degradation of power transformer using ultrasonic signal through ultrasonic transducer attached surface of power transformer. And also it makes possible to reduce power failure time due to the power transformer fault and makes power system more reliable. Ultrasonic diagnostic device for power transformer was developed through this study. The developed device will contributed to early detection of fault and its location in the power transformer while it is operated, and also to extension of transformer life cycle, localization of this device will be reduced it's cost down compared with off shore. This device consisted of a new diagnostic algorithm is well suited for the power transformer which could found out some fault during the operation of on line monitoring system. This system could be extended to the general industrial plant utilizing the accumulated diagnostic technique.

  4. A study on the diagnosis for power transformer by ultrasonic wave detection(2)

    International Nuclear Information System (INIS)

    The objectives of this study is to develop a device which could diagnose periodically the degradation of power transformer using ultrasonic signal through ultrasonic transducer attached surface of power transformer. And also it makes possible to reduce power failure time due to the power transformer fault and makes power system more reliable. Ultrasonic diagnostic device for power transformer was developed through this study. The developed device will contributed to early detection of fault and its location in the power transformer while it is operated, and also to extension of transformer life cycle, localization of this device will be reduced it's cost down compared with off shore. This device consisted of a new diagnostic algorithm is well suited for the power transformer which could found out some fault during the operation of on line monitoring system. This system could be extended to the general industrial plant utilizing the accumulated diagnostic technique.

  5. A study on the diagnosis for power transformer by Ultrasonic wave detection (2)

    International Nuclear Information System (INIS)

    The objectives of this study is to develop a device which could diagnosis periodically the degradation of power transformer using ultrasonic signal through ultrasonic transducer attached surface of power transformer. And also it makes possible to reduce power failure time due to the power transformer fault and makes power system more reliable. Ultrasonic diagnostic device for power transformer was developed through this study. The developed device will contributed to early detection of fault and its location in the power transformer while it is operated, and also to extension of transformer life cycle, localization of this device will be reduced it's cost down compared with off shore. This device consisted of a new diagnostic algorithm is well suited for the power transformer which could found out some fault during the operation of on line monitoring system. This system could be extended to the general industrial plant utilizing the accumulated diagnostic technique.

  6. Improved corner detection by ultrasonic testing using phase analysis.

    Science.gov (United States)

    Broberg, Patrik; Runnemalm, Anna; Sjödahl, Mikael

    2013-02-01

    In ultrasonic testing, corners are used for sensitivity calibration in the form of notches, for measuring the sound velocity in the material, and as known reference points during testing. A 90° corner will always reflect incoming waves in the opposite direction due to a double reflection and therefore give a strong echo. This article presents a method for separating the echo from a corner from other echoes and more accurately find the position of the corner. The method is based on analysing the phase of the reflected signal. The proposed method was tested on a steel calibration block and the width of the indication was reduced by up to 50% compared to the amplitude signal. This results in a more accurate positioning of the corner. Using the phase instead of the amplitude will also improve the reliability, since reflections other than from corners will disappear. PMID:23164172

  7. Effect of stress on ultrasonic response in detection and sizing of cracks

    Energy Technology Data Exchange (ETDEWEB)

    Laukkanen, A. [VTT Manufacturing Technology, Materials and Structural Integrity, Espoo (Finland); Kemppainen, M.; Virkkunen, I. [Trueflaw ltd (Finland); Pitkaenen, J.

    2007-07-01

    In different NDT techniques huge developments have been achieved during the last few years with regard to crack detection and sizing. In a large range of materials, cracks are one of the most dangerous defect types. A crack is a planar reflector, which is sometimes extremely difficult to detect and to be sized. A crack can be totally open, partly closed or even totally closed because of compressive stresses. The effects of stresses cause problems, for instance, in inservice inspections of nuclear power plants in detection and sizing of closed cracks. This phenomenon causes similar effects in all kinds of plants and components. In this study some experimental inspections have been carried out as well as some FEM calculations of stress field around the crack and compared to corresponding measurements in literature. Materials used for this study are austenitic and ferritic piping steel. The dynamic load applied to the cracks was in form of different thermal cycles. The maximum temperature variations were from 20 C to 600 C depending on each dynamic loading cycle. Different types of ultrasonic methods were used in the measurements. The effect of closure on the response of normal ultrasonic practical probes was recorded. Dynamic loading during ultrasonic measurement gives clear evidence on the effect of the crack closure as well as on the amplitude variation limits in ultrasonic testing. (orig.)

  8. Gas leak localization and detection method based on a multi-point ultrasonic sensor array with TDOA algorithm

    Science.gov (United States)

    Tao, Wang; Dongying, Wang; Yu, Pei; Wei, Fan

    2015-09-01

    To resolve the measured target position to determine and locate leak problems with current gas leak detection and localization systems based on ultrasonic technology, this paper presents an improved multi-array ultrasonic gas leak TDOA (time difference of arrival) localization and detection method. This method involves arranging ultrasonic transducers at equal intervals in a high-sensitivity detector array, using small differences in ultrasonic sound intensity to determine the scope of the leak and generate a rough localization, and then using an array TDOA localization algorithm to determine the precise leak location. This method is then implemented in an ultrasonic leak detection and localization system. Experimental results showed that the TDOA localization method, using auxiliary sound intensity factors to avoid dependence on a single sound intensity to determine the leak size and location, achieved a localization error of less than 2 mm. The validity and correctness of this approach were thus verified.

  9. Detection of cracks in stud bolts of nuclear reactor by novel ultrasonic technique

    International Nuclear Information System (INIS)

    The stud bolt is one of the most critical parts for the safety of reactor vessels in nuclear power plants. However, in the practical application of ultrasonic technique for crack detection in stud bolt, the classification of crack signal from the signals reflected from threads in stud bolt is very difficult. In this study, shadow effect technique combined with new signal processing method has been investigated to enhance the detectability of small crack initiated from root of thread in stud bolt. The key idea of new signal processing concept is based on the fact that the shape of waveforms from the threads is uniform since the shape of the threads in a bolt is same. If some cracks exist in the thread, the flaw signals are different from the reference signals. It has shown that the small flaws can be effectively detected by novel ultrasonic technique combined with this new signal processing concept. (orig.)

  10. Enhancement of crack detection in stud bolts of nuclear reactor by ultrasonic signal processing technique

    International Nuclear Information System (INIS)

    'Full-text:' The stud bolts is one of the most critical parts for safety of reactor vessels in the nuclear power plants. However, in the application of ultrasonic technique for crack detection in stud bolt, some difficulties encountered are classification of crack signal from the signals reflected from threads part in stud bolt. In this study, shadow effect technique combined with new signal processing method is Investigated to enhance the detectability of small crack initiated from root of thread in stud bolt. The key idea of signal processing is based on the fact that the shape of waveforms from the threads is uniform since the shape of the threads in a bolt is same. If some cracks exist in the thread, the flaw signals are different to the reference signals. It is demonstrated that the small flaws are efficiently detected by novel ultrasonic technique combined with this new signal processing concept. (author)

  11. Enhancement of crack detection in stud bolts of nuclear reactor by ultrasonic signal processing technique

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.H.; Oh, W.D.; Choi, S.W.; Park, M.H. [Busan National Univ., Busan (Korea, Republic of)

    2004-07-01

    'Full-text:' The stud bolts is one of the most critical parts for safety of reactor vessels in the nuclear power plants. However, in the application of ultrasonic technique for crack detection in stud bolt, some difficulties encountered are classification of crack signal from the signals reflected from threads part in stud bolt. In this study, shadow effect technique combined with new signal processing method is Investigated to enhance the detectability of small crack initiated from root of thread in stud bolt. The key idea of signal processing is based on the fact that the shape of waveforms from the threads is uniform since the shape of the threads in a bolt is same. If some cracks exist in the thread, the flaw signals are different to the reference signals. It is demonstrated that the small flaws are efficiently detected by novel ultrasonic technique combined with this new signal processing concept. (author)

  12. Improved Detection of Tendon Ducts and Defects in Concrete Structures Using Ultrasonic Imaging

    International Nuclear Information System (INIS)

    At the beginning of the 90's the general opinion was, that ultrasonic inspection methods using pulse-echo technique were not suitable for the inspection of concrete because of the inhomogeneity and the strong scattering behavior of the embedded aggregates. In the meantime the progress in the development of new equipment and inspection strategies in connection with ultrasonic imaging techniques turns the pulse-echo technique into a powerful tool to solve problems related to concrete materials. These imaging techniques - developed for the inspection of homogenous materials like steel or aluminum - could be adopted to the very low frequencies needed for concrete inspections. Since 1994 the BAM and the IZFP cooperate in the field of concrete inspection. The BAM performs measurements using laser-vibro-meters, probe-arrays, and pitch-and-catch arrangements with two probes. The ultrasonic echoes received are digitized and stored on a computer and evaluated at the IZFP using the Synthetic Aperture Focusing Technique (SAFT) for 3-dimensional imaging. The results are very encouraging with respect to detection and positioning of reinforcement structures inside the concrete like tendon ducts and reinforcement bars as well as defects like compaction defects and voids (honey-combing represented by styrodur balls) and to detect and even size notches and natural cracks oriented vertical to the surface. These inspections are applied to bridges, non-ballasted tracks, and foundation slabs. They were performed in the laboratory as well as in the field at prestressed concrete bridges. In addition the Federal Highway Research Institute (Bundesanstalt fuer Strassenwesen, BAST) organized two round robin trials, one on test specimen containing artificial defects, the other on a motorway bridge, which had to be replaced. Examples of reconstructed ultrasonic images are presented. Further basic research work on ultrasonic imaging of concrete structures is carried out within a research group

  13. Detection of hydride blister in PHWR pressure tubes using ultrasonic velocity ratio method

    International Nuclear Information System (INIS)

    When the pressure tubes(PT) contact to the calandria tube(CT) in the pressurized heavy water reactor(PHWR), the temperature difference between inner and outer wall of PT results in a thermal diffusion of hydrogen (deuterium) and hydride blisters are formed on the outer surface of PT. Because the hydride blisters are acoustically continued to zirconium matrix, it is not easy to detect the blisters with conventional ultrasonic method. An ultrasonic velocity ratio method was developed to detect small hydride blisters on the zirconium pressure tube. Hydride blisters were grown in the PT specimen with a steady state thermal diffusion device. Ultrasonic velocity ratio method were developed for detection of hydride blisters. The flight time of longitudinal echo and reflected shear echo from the outer surface were measured and calculated to the parameter of velocity ratio of longitudinal wave to shear wave. The velocity ratio was plotted to modified c-scan display and converted to contour plot. The plots shows the capability that the blisters could be detected as well as imaged the shapes.

  14. Ultrasonic physics

    CERN Document Server

    Richardson, E G

    1962-01-01

    Ultrasonic Physics, Second Edition, provides an introduction to the fundamental principles of ultrasonic physics. The book opens with a discussion of the sources of ultrasound. This is followed by separate chapters on the properties and detection of ultrasonic radiation; measurement of propagation constants, i.e., the velocity and absorption, of ultrasound; ultrasound propagation in gases, liquids, and solids; and ultrasound propagation in aerosols, suspensions, and emulsions. The final chapter covers miscellaneous physical and physico-chemical actions, including dispersion and coagulation of

  15. Rapid Detection of high-level oncogene amplifications in ultrasonic surgical aspirations of brain tumors

    Directory of Open Access Journals (Sweden)

    Truong Long N

    2012-06-01

    Full Text Available Abstract Background Genomic tumor information, such as identification of amplified oncogenes, can be used to plan treatment. The two sources of a brain tumor that are commonly available include formalin-fixed, paraffin-embedded (FFPE sections from the small diagnostic biopsy and the ultrasonic surgical aspiration that contains the bulk of the tumor. In research centers, frozen tissue of a brain tumor may also be available. This study compared ultrasonic surgical aspiration and FFPE specimens from the same brain tumors for retrieval of DNA and molecular assessment of amplified oncogenes. Methods Surgical aspirations were centrifuged to separate erythrocytes from the tumor cells that predominantly formed large, overlying buffy coats. These were sampled to harvest nuclear pellets for DNA purification. Four glioblastomas, 2 lung carcinoma metastases, and an ependymoma were tested. An inexpensive PCR technique, multiplex ligation-dependent probe amplification (MLPA, quantified 79 oncogenes using 3 kits. Copy number (CN results were normalized to DNA from non-neoplastic brain (NB in calculated ratios, [tumor DNA]/[NB DNA]. Bland-Altman and Spearman rank correlative comparisons were determined. Regression analysis identified outliers. Results Purification of DNA from ultrasonic surgical aspirations was rapid ( Conclusions Buffy coats of centrifuged ultrasonic aspirations contained abundant tumor cells whose DNA permitted rapid, multiplex detection of high-level oncogene amplifications that were confirmed in FFPE. Virtual slides http://www.diagnosticpathology.diagnomx.eu/vs/1883718801686466

  16. Feature extraction for ultrasonic sensor based defect detection in ceramic components

    Science.gov (United States)

    Kesharaju, Manasa; Nagarajah, Romesh

    2014-02-01

    High density silicon carbide materials are commonly used as the ceramic element of hard armour inserts used in traditional body armour systems to reduce their weight, while providing improved hardness, strength and elastic response to stress. Currently, armour ceramic tiles are inspected visually offline using an X-ray technique that is time consuming and very expensive. In addition, from X-rays multiple defects are also misinterpreted as single defects. Therefore, to address these problems the ultrasonic non-destructive approach is being investigated. Ultrasound based inspection would be far more cost effective and reliable as the methodology is applicable for on-line quality control including implementation of accept/reject criteria. This paper describes a recently developed methodology to detect, locate and classify various manufacturing defects in ceramic tiles using sub band coding of ultrasonic test signals. The wavelet transform is applied to the ultrasonic signal and wavelet coefficients in the different frequency bands are extracted and used as input features to an artificial neural network (ANN) for purposes of signal classification. Two different classifiers, using artificial neural networks (supervised) and clustering (un-supervised) are supplied with features selected using Principal Component Analysis(PCA) and their classification performance compared. This investigation establishes experimentally that Principal Component Analysis(PCA) can be effectively used as a feature selection method that provides superior results for classifying various defects in the context of ultrasonic inspection in comparison with the X-ray technique.

  17. A novel method for detecting second harmonic ultrasonic components generated from fastened bolts

    Science.gov (United States)

    Fukuda, Makoto; Imano, Kazuhiko

    2012-09-01

    This study examines the use of ultrasonic second harmonic components in the quality control of bolt-fastened structures. An improved method for detecting the second harmonic components, from a bolt fastened with a nut, using the transmission method is constructed. A hexagon head iron bolt (12-mm diameter and 25-mm long) was used in the experiments. The bolt was fastened using a digital torque wrench. The second harmonic component increased by approximately 20 dB before and after the bolt was fastened. The sources of second harmonic components were contact acoustic nonlinearity in the screw thread interfaces of the bolt-nut and were the plastic deformation in the bolt with fastening bolt. This result was improved by approximately 10 dB compared with previous our method. Consequently, usefulness of the novel method for detecting second harmonic ultrasonic components generated from fastened bolt was confirmed.

  18. Characterization and comparison of defects detection limits of three ultrasonic non destructive methods

    Directory of Open Access Journals (Sweden)

    Welemane H.

    2010-06-01

    Full Text Available This work deals with the Liquid Resin Infusion (LRI process developed within the research program “FUSelage COMPosite” of DAHER SOCATA. This manufacturing process enables the realization of complex composite structures or fuselage elements in a single phase (mono-material, which considerably reduce connections and relative difficulties. The concern here is the investigation of non destructive testing (NDT methods that can be applied to LRI-structures in order to define their capacities for defect detection, and especially their associated critical defect size. In aviation industry, the AITM standards require the ultrasonic testing as NDT for composite materials. Therefore the aim of this work is to characterize and compare three different and complementary ultrasonic techniques on composite specimens. Such analysis allows to define the NDT application field of each method in term of defect detection.

  19. Ultrasonic damage detection of concrete structures by using pulse-echo sensor arrays and SAFT

    Science.gov (United States)

    Shi, Li-hua; Shao, Zhi-xue; Shao, Zhe

    2009-07-01

    In ultrasonic nondestructive testing (NDT) of concrete structures, the synthetic aperture focusing technique (SAFT) can improve the resolution of target and therefore gives a better image display of the B-scan data. In traditional B-scan of concrete structures the ultrasonic transducers are usually moved manually to detect the whole structure, the detection speed and the consistency in different test points are greatly affected. A PZT sensor array is designed in this paper to perform B-scan on large concrete structures more efficiently. The excitation of the sensor array and the data processing techniques for the array data are discussed. A signal processing approach is proposed to improve the consistency between different test channels in the array. Experiments on real structures show the embedded objects can be located accurately by using the array sensor and SAFT method.

  20. A SENSITIVE AND STABLE CONFOCAL FABRY-PEROT INTERFEROMETER FOR SURFACE ULTRASONIC VIBRATION DETECTION

    Institute of Scientific and Technical Information of China (English)

    DING HONG-SHENG; TONG LI-GE; CHEN GENG-HUA

    2001-01-01

    A new confocal Fabry-Pérot interferometer (CFPI) has been constructed. By using both of the conjugate rays,the sensitivity of the system was doubled. Moreover, the negative feedback control loop of a single-chip microcomputer (MCS-51) was applied to stabilize the working point at an optimum position. The system has been used in detecting the piezoelectric ultrasonic vibration on the surface of an aluminium sample.

  1. A new ultrasonic method to detect chemical additives in branded milk

    Indian Academy of Sciences (India)

    S Mohanan; P G Thomas Panicker; Lilly Iype; M Laila; I Domini; R G Bindu

    2002-09-01

    A new ultrasonic method – thermoacoustic analysis – is reported for the detection of the added chemical preservatives in branded milk. The nature of variation and shift in the thermal response of the acoustic parameters specific acoustic impedance, adiabatic compressibility and Rao’s specific sound velocity for different samples of branded milk as compared to the chemical added pure milk are explained as due to the presence of chemicals in these branded samples.

  2. Detection of Hydride Blisters in Zirconium Pressure Tubes using Ultrasonic Mode Conversion and Velocity Ratio Method

    International Nuclear Information System (INIS)

    When the pressure tubes(f are in contact with the calandria tube(CT) in the pressurized heavy water reactor(PHWR), the temperature difference between inner and outer wall of W results in a thermal diffusion of hydrogen (deuterium) and hydride blisters are formed on the outer surface of PT. Because the hydride blisters and zirconium matrix are acoustically continuous, it is not easy to distinguish the blisters from the matrix with conventional ultrasonic method. An ultrasonic velocity ratio method was developed to detect small hydride blisters on the zirconium pressure tube. Hydride blisters were grown in the PT specimen using a steady state thermal diffusion device. The flight times of longitudinal echo and reflected shear echo from the outer surface were measured accurately. The velocity ratio of the longitudinal wave to the shear wave was calculated and displayed using contour plot. Compared to the conventional flight time method of longitudinal wave, the velocity ratio method shows superior sensitivity to detect smaller blisters as well as better images for the blister shapes. Detectable limit of the outer shape of the hydride blisters was conservatively estimated as 50μm, with the same specifications of ultrasonic transducer used in the actual PHWR pressure tube inspection

  3. A control system of mobile navigation robot for precise spraying based ultrasonic detecting and ARM embedded technologies

    Science.gov (United States)

    Tang, Xiuying; Li, Cuiling; Wang, Xiu; Yue, Xinpeng; Peng, Yankun

    2011-06-01

    This paper described a control system of mobile navigation robot for precision spraying in greenhouse environment, which were composed of main control module, motor driving module, ultrasonic detecting module and wirless remote control module. The hard circuits of control system were built. The main control module used ARM7TDMI-S-based LPC2210 micro-processing controller. The motor driving module consisted of voltage amplifier circuit based SN74LS245N and DM74LS244N chips, RC filter circuit, and HM-YZ-30 DC brush motor driver. The ultrasonic detecting module consisted of four standard ultrasonic ranging modules which were arranged on the four sides around the mobile navigation robot, and used GM8125 chip to expand serial communication interfaces. An obstacle-avoiding strategy and its algorithm were proposed and the control programs of mobile navigation robot were programmed. The mobile navigation robot for spraying can realize the actions such as starting and stopping, forward and backward moving, accelerate and decelerate motion, and right and left turn. Finally, the functional experiments of the mobile navigation robot were conducted in the laboratory environment. The results showed that the ultrasonic detecting distance of the robot was 50.5mm-1832.0mm and detecting blind zone was less than 50mm, the ultrasonic detecting angle of individual ultrasonic detecting module of robot was similar to U-shaped and its vaule was about 45.66°, and the moving path of navigation robot was approximately linear.

  4. A Laser-based Ultrasonic Inspection System to Detect Micro Fatigue Cracks

    International Nuclear Information System (INIS)

    Laser-based ultrasonic techniques have been established as a viable non-contact alternative to piezoelectric transducers for generating and receiving ultrasound. Laser-based ultrasonic inspection system provides a number of advantages over the conventional generation by piezoelectric transducers, especially a non-contact generation and detection of ultrasonic waves, high spatial scanning resolution, controllable narrow-band and wide-band spectrum, absolute measurements of the moving distance, use of fiber optics, and an ability to operate on curved and rough surfaces and at hard-to-access locations like a nuclear power plant. Ochiai and Miura used the laser-based ultrasound to detect micro fatigue cracks for the inspection of a material degradation in nuclear power plants. This widely applicable laser-based ultrasonic inspection system is comparatively expensive and provides low signal-to-noise ratio to measure ultrasound by using the laser interferometer. Many studies have been carried out to improve the measuring efficiency of the laser interferometer. One of the widely used laser interferometer types to measure the ultrasound is the Confocal Fabry-Perot Interferometer(CFPI). The measurement gain of the CFPI is slightly and continually varied according to the small change of the cavity length and the fluctuations of the measuring laser beam frequency with time. If we continually adjust the voltage of a PZT which is fixed to one of the interferometer mirrors, the optimum working point of the CFPI can be fixed. Though a static stabilizer can fix the gain of the CFPI where the CW laser beam is targeted at one position, it can not be used when the CW laser beam is scanned like a scanning laser source(SLS) technique. A dynamic stabilizer can be used for the scanning ultrasonic inspection system. A robust dynamic stabilizer is needed for an application to the industrial inspection fields. Kromine showed that the SLS technique is effective to detect small fatigue cracks

  5. An efficient decomposition technique to solve angle-dependent Hanle scattering problems

    CERN Document Server

    Supriya, H D; Nagendra, K N; Ravindra, B; Anusha, L S; 10.1016/j.jqsrt.2012.12.016

    2013-01-01

    Hanle scattering is an important diagnostic tool to study weak solar magnetic fields. Partial frequency redistribution (PRD) is necessary to interpret the linear polarization observed in strong resonance lines. Usually angle-averaged PRD functions are used to analyze linear polarization. However it is established that angle-dependent PRD functions are often necessary to interpret polarization profiles formed in the presence of weak magnetic fields. Our aim is to present an efficient decomposition technique, and the numerical method to solve the concerned angle-dependent line transfer problem. Together with the standard Stokes decomposition technique we employ Fourier expansion over the outgoing azimuth angle to express in a more convenient form, the angle-dependent PRD function for the Hanle effect. It allows the use of angle-dependent frequency domains of Bommier to solve the Hanle transfer problem. Such an approach is self-consistent and accurate compared to a recent approach where angle-averaged frequency ...

  6. Wireless ultrasonic wavefield imaging via laser for hidden damage detection inside a steel box girder bridge

    International Nuclear Information System (INIS)

    This paper presents a wireless ultrasonic wavefield imaging (WUWI) technique for detecting hidden damage inside a steel box girder bridge. The proposed technique allows (1) complete wireless excitation of piezoelectric transducers and noncontact sensing of the corresponding responses using laser beams, (2) autonomous damage visualization without comparing against baseline data previously accumulated from the pristine condition of a target structure and (3) robust damage diagnosis even for real structures with complex structural geometries. First, a new WUWI hardware system was developed by integrating optoelectronic-based signal transmitting and receiving devices and a scanning laser Doppler vibrometer. Next, a damage visualization algorithm, self-referencing f-k filter (SRF), was introduced to isolate and visualize only crack-induced ultrasonic modes from measured ultrasonic wavefield images. Finally, the performance of the proposed technique was validated through hidden crack visualization at a decommissioned Ramp-G Bridge in South Korea. The experimental results reveal that the proposed technique instantaneously detects and successfully visualizes hidden cracks even in the complex structure of a real bridge. (paper)

  7. Wireless ultrasonic wavefield imaging via laser for hidden damage detection inside a steel box girder bridge

    Science.gov (United States)

    An, Yun-Kyu; Song, Homin; Sohn, Hoon

    2014-09-01

    This paper presents a wireless ultrasonic wavefield imaging (WUWI) technique for detecting hidden damage inside a steel box girder bridge. The proposed technique allows (1) complete wireless excitation of piezoelectric transducers and noncontact sensing of the corresponding responses using laser beams, (2) autonomous damage visualization without comparing against baseline data previously accumulated from the pristine condition of a target structure and (3) robust damage diagnosis even for real structures with complex structural geometries. First, a new WUWI hardware system was developed by integrating optoelectronic-based signal transmitting and receiving devices and a scanning laser Doppler vibrometer. Next, a damage visualization algorithm, self-referencing f-k filter (SRF), was introduced to isolate and visualize only crack-induced ultrasonic modes from measured ultrasonic wavefield images. Finally, the performance of the proposed technique was validated through hidden crack visualization at a decommissioned Ramp-G Bridge in South Korea. The experimental results reveal that the proposed technique instantaneously detects and successfully visualizes hidden cracks even in the complex structure of a real bridge.

  8. Ultrasonic detection of laminar-type defects in iridium alloy blanks

    Energy Technology Data Exchange (ETDEWEB)

    Cook, K.V.; Cunningham, R.A. Jr.; Simpson, W.A. Jr.; McClung, R.W.

    1986-07-01

    Encapsulated isotopic heat sources for use in generating electrical power for space applications require flight-quality hardware material. Iridium is the chosen material for such applications, and Oak Ridge National Laboratory has been the prime supplier of iridium alloy forming blanks 52 mm in diameter by 0.66 mm thick (1.0 by 0.026 in.). Prior to the work reported here, these blanks were ultrasonically examined by using 0.9-mm-diam (0.035-in.) simulated flaw standards. However, as a result of this effort, the sensitivity of our ultrasonic pulse-echo test system has been increased. The improved ultrasonic test system permits blank inspection at the 0.5-mm-diam (0.020-in.) simulated flaw detection level. This test system was successfully demonstrated on the initial blanks provided via an improved processing route (consumable arc-melting, extruding, and rolling). The equipment modification and/or selection and the specific focused search unit immersion technique developed to provide this capability are described. The improved flaw detection capability also provides data maps of a common type of defect in iridium (delaminations).

  9. Reference-free fatigue crack detection using nonlinear ultrasonic modulation under various temperature and loading conditions

    Science.gov (United States)

    Lim, Hyung Jin; Sohn, Hoon; DeSimio, Martin P.; Brown, Kevin

    2014-04-01

    This study presents a reference-free fatigue crack detection technique using nonlinear ultrasonic modulation. When low frequency (LF) and high frequency (HF) inputs generated by two surface-mounted lead zirconate titanate (PZT) transducers are applied to a structure, the presence of a fatigue crack can provide a mechanism for nonlinear ultrasonic modulation and create spectral sidebands around the frequency of the HF signal. The crack-induced spectral sidebands are isolated using a combination of linear response subtraction (LRS), synchronous demodulation (SD) and continuous wavelet transform (CWT) filtering. Then, a sequential outlier analysis is performed on the extracted sidebands to identify the crack presence without referring any baseline data obtained from the intact condition of the structure. Finally, the robustness of the proposed technique is demonstrated using actual test data obtained from simple aluminum plate and complex aircraft fitting-lug specimens under varying temperature and loading variations.

  10. Control system for detecting cut-time of milk coagulation using ultrasonic method

    Science.gov (United States)

    Wen, Youxian; Liu, Jianyin; Yu, Liming; Gunasekaran, Sundaram

    1993-09-01

    The research developed new and non-destructive method to detect the cutting time of milk coagulation. The system used for estimating cut-time of milk coagulation consisted of a high frequency signal generator transmitter and receiver transducers computerized data acquisition and control executive circuits. When input signal frequency equals to the inherent frequency of the ultrasonic transducer-milk coagulation system the output signal of the receiver transducer is the same frequency sine wave as that of the emit transducer and only different on their amplitude. The RMS. to DC conversion designed converted the high frequency signal into dc signal so that the computer can process easily it. The whole control system was operated by running designed EASYEST program and the clotting time(turning point) and cutting time(cutting point) was determined automatically. The experiments running the control system in laboratory produced positive correlation between the attenuation of ultrasonic signal and the physical property of milk coagulation.

  11. Ultrasonic non-destructive evaluation for characterisation, microdefects detection and imaging of industrial/medical based materials

    International Nuclear Information System (INIS)

    The ultrasonic non-destructive evaluation (NDE) has emerged as one of the powerful methods to characterise the materials. The recent adventure of electronics and computers lead to tremendous developments in the field of ultrasonics NDE. In the present paper an attempt has been made to characterise the industrial based materials such as semiconducting glasses, superconducting glass and glass ceramics and bio active glasses through ultrasonic NDE. The factors like surface defects, subsurface defects etc. can not be studied using the traditional ultrasonics NDT and other methods. However, microdefects detection and imaging of the above materials will give a better insight into the properties of the above materials. Therefore, the basic principle, operation and application of scanning acoustic microscopy has been discussed briefly for the NDE of microdefects detection and imaging of the materials. (author)

  12. Flow angle dependent photoacoustic Doppler power spectra under intensity-modulated continuous wave laser excitation

    Directory of Open Access Journals (Sweden)

    Yu Tong

    2016-02-01

    Full Text Available Photoacoustic Doppler (PAD power spectra showing an evident Doppler shift represent the major characteristics of the continuous wave-excited or burst wave-excited versions of PAD flow measurements. In this paper, the flow angle dependences of the PAD power spectra are investigated using an experiment setup that was established based on intensity-modulated continuous wave laser excitation. The setup has an overall configuration that is similar to a previously reported configuration, but is more sophisticated in that it accurately aligns the laser illumination with the ultrasound detection process, and in that it picks up the correct sample position. In the analysis of the power spectra data, we find that the background power spectra can be extracted by combining the output signals from the two channels of the lock-in amplifier, which is very useful for identification of the PAD power spectra. The power spectra are presented and analyzed in opposite flow directions, at different flow speeds, and at different flow angles. The power spectra at a 90° flow angle show the unique properties of symmetrical shapes due to PAD broadening. For the other flow angles, the smoothed power spectra clearly show a flow angle cosine relationship.

  13. Study on flaw detection and evaluation technique for turbine rotor disc using ultrasonic inspection

    International Nuclear Information System (INIS)

    Rim or web part of the turbine rotor disc can be inspected by magnetic test(MT) or penetration test(PT) because of easy accessibility to them. but, unless disc is separated from a rotor, above NDT inspection of hub, keyway part and bore surface is not applicable because of difficult accessibility to them. MT method which has been used for inspection of the LP turbine disc, should be replaced by a new method as it has caused an increase of the manpower followed by blade separation and prolonged shut-down periods. So, ultrasonic inspection that can be inspected promptly and elucidated crack size, is urgently required for a disc, and can not but depend on this method. However, due to complexity of their shape and structure, and unestablishment of inspection technique, ultrasonic inspection for a disc has many difficulties such as inspection method, flaw evaluation and signal analysis etc. Thus, in this study, ultrasonic inspection technique to detect and assess flows occurred in turbine rotor disc was developed, and also their inspection procedure was established for guarantee of safety and reliability on turbine for a power plant.

  14. Ultrasonic Detection of Delamination and Material Characterization of Thermal Barrier Coatings

    Science.gov (United States)

    Chen, Hung-Liang Roger; Zhang, Binwei; Alvin, Mary Anne; Lin, Yun

    2012-12-01

    This article describes ultrasonic nondestructive evaluation (NDE) to detect the changes of material properties and provide early warning of delamination in thermal barrier coating (TBC) systems. NDE tests were performed on single-crystal René N5 superalloy coupons that were coated with a commercially available MCrAlY bond coat and an air plasma sprayed 7% yttria-stabilized zirconia (YSZ) top coat deposited by Air Plasma Spray method, as well as Haynes 230 superalloy coupons coated with MCrA1Y bond coat, and an electron beam physical vapor deposit of 7% YSZ top coat. The TBC coupons were subjected to either cyclic or isothermal exposure for various lengths of time at temperatures ranging from 900 to 1100 °C. The ultrasonic measurements performed on the coupons had provided an early warning of delamination along the top coat/TGO interface before exposure time, when delamination occurred. The material's property (Young's modulus) of the top coat was estimated using the measured wave speeds. Finite element analysis (FEA) of the ultrasonic wave propagation was conducted on a simplified TBC system to verify experimental observations. The technique developed was also demonstrated on an as-manufactured turbine blade to estimate normalized top coat thickness measurements.

  15. Cladding flaw detection and sizing by horizontally polarized shear wave ultrasonic EMAT transducers

    International Nuclear Information System (INIS)

    Further experimental work was done within the framework of the current research contract on the employment of the EMAT technique in the ultrasonic inspection of reactor vessel cladding. This year's activity focused on the study of the space distribution of the ultrasonic beam generated by the flexible transducers developed during the course of the previous year, and on the inspection of the cladding of the JRC-ISPRA PWR vessel 1:5 scale model. Two transducer pairs were used to make laboratory measurements on the clad and unclad test block sides for the purpose of studying ultrasonic beam distribution. It emerged that the cladding tended to confine the beam. If however the wavelength was equal to or greater than the cladding thickness the confinement was not complete and became less and less evident with increasing wavelength. It was consequently possible to pick up echoes produced by flaws located both within the cladding and in the underlaying layers. The PWR vessel model cladding was then inspected in the neighbourhood of the welds and a large number of flaws was found. The EMAT technique has proved to be suitable for the detection and rough location of flaws but less so for their sizing, although in some cases it was possible to assess the distance between the flaw and the cladding top

  16. Development of ultrasonic inspection technique for crack detection in retaining rings

    International Nuclear Information System (INIS)

    The majority of retaining rings which are currently in service, are composed of a material which is susceptible to stress corrosion when exposed to moisture. Due to the inherent stress levels in the shrunk-on areas, they are particularly susceptible to stress corrosion attack. Therefore, retaining rings require non-destructive examination to avert catastrophic failure. Guidelines for retaining ring inspection issued by EPRI recommend ultrasonic manual and automated methods of inspection for rings in place. Application of the conventional manual method, using S-waves is difficult, and yields unreliable results. Due to the unreliability factor, utilities have been forced to depend upon surface examination methods, such as visual and penetrant techniques. In most instances, a surface exam will necessitate the costly and potentially damaging removal of the rings from the rotor to provide full access to areas of interest. Due to the various complexities of conventional ultrasonic retaining ring inspections, it is essential that the front end ultrasonics (i.e., transducers and techniques) be optimized to produce the best possible examination. For this reason, AMDATA has developed custom transducers and techniques to enhance automated detection capability of flaws in the various suspect areas of retaining rings. When the optimized techniques are applied to generate the best possible raw data, the Intraspect /98 trademark is then used to reliably apply technique, acquire the data and perform post processing evaluations. One of the most promising ultrasonic techniques for retaining ring inspection is creeping waves. This paper investigates the use of creeping waves for retaining ring inspection

  17. Detection of Arterial Wall Boundaries Using an Echo Model Composed of Multiple Ultrasonic Pulses

    Science.gov (United States)

    Ibrahim, Nabilah; Hasegawa, Hideyuki; Kanai, Hiroshi

    2013-07-01

    The assessment of the intima-media thickness (IMT) of the carotid arterial wall, which is the most frequently used indicator to diagnose atherosclerosis by ultrasound, involves the measurement of the lumen-intima boundary (LIB) and media-adventitia boundary (MAB). In this study, using the mean squared error (MSE) method and by applying the template matching technique, an adaptive model of an ultrasonic echo, which is obtained from an ultrasonic pulse measured with a hydrophone, was fitted with the measured in vivo RF echo to estimate the boundaries of the carotid arterial wall. In the present study, the frequency and phase of the adaptive model were considered to improve the accuracy in the determination of the LIB and MAB. For a 7.5-mm-long short segment of the carotid artery in the longitudinal direction, the average IMTs estimated by the improved technique and the previous method were 502+/-61 and 558+/-120 µm, respectively, showing a decrease in the standard deviation by the proposed method. Moreover, the result obtained by the improved technique presented only 0.4% difference between the automatically detected boundary and the manually detected boundary, which is smaller than that obtained by the previous method (10.7% difference). These results verified that the boundary detected by the improved technique was more accurate than that detected by the previous method.

  18. Generation and detection of ultrasonic waves with no contact by electromagnetic way

    International Nuclear Information System (INIS)

    This work is not only to study and analyse the electromagnetic generation and detection of ultrasonic waves, but to investigate their possible application in nondestructive testing of materials as well. The theory has been based upon the analysis of two magnetic effects. These are namely: the magnetostrictive effect and the electrodynamic effect. The analysis of the latter effect has been founded upon a macroscopic and a microscopic model. For each model, the propagation equation of the electromagnetically produced acoustic waves has been established and resolved. In the microscopic model, two cases have been considered: generation with static induction superposition. Generation without static induction superposition. As regards detection, only the generation with static induction superposition has been considered. Longitudinal and transverse waves have been experimentally generated and detected in steel, aluminium, and copper. The following parameters have been analysed: The static induction effect. The nature propagation medium. The effect of the distance between the generating coil and for receiving one and the material surface. The effect of coil characteristics. Finally, the possibility of generating and detecting ultrasonic waves has been analysed using a single coil in a combined emission - reception mode

  19. Ultrasonic array for obstacle detection based on CDMA with Kasami codes.

    Science.gov (United States)

    Diego, Cristina; Hernández, Alvaro; Jiménez, Ana; Alvarez, Fernando J; Sanz, Rebeca; Aparicio, Joaquín

    2011-01-01

    This paper raises the design of an ultrasonic array for obstacle detection based on Phased Array (PA) techniques, which steers the acoustic beam through the environment by electronics rather than mechanical means. The transmission of every element in the array has been encoded, according to Code Division for Multiple Access (CDMA), which allows multiple beams to be transmitted simultaneously. All these features together enable a parallel scanning system which does not only improve the image rate but also achieves longer inspection distances in comparison with conventional PA techniques. PMID:22247675

  20. Highly Sensitive Detection of Red Blood Cell Aggregation with Ultrasonic Peak Frequency

    Science.gov (United States)

    Sato, Takayuki; Tojo, Hiroyuki; Watanabe, Yasuaki

    2013-07-01

    A novel technique of detecting the peak frequency of an ultrasonic reflection spectrum was proposed, with the aim of enhancing the sensitivity and accuracy of estimating the aggregation size of red blood cells (RBCs). Peak frequencies for stagnant and running suspensions prepared with monodisperse particles of graphite and acryl that were used to mimic aggregated RBCs were acquired. As a result, the relationships between particle diameter and peak frequency, which were independent of the material of the particles and flow rate, were obtained. For bidisperse samples, i.e., mixtures of two different sizes of particle samples, quantitative relationships corresponding to changes in the mixing ratio were observed.

  1. Generation of ultrasonic wave by a pulsed Nd:YAG laser and application of detection of defects

    International Nuclear Information System (INIS)

    Conventional ultrasonic evaluation is the contacting method by using transducer and couplant. Thus it not applied the material with high temperature, movement. Substitutionally a laser pulse irradiated on a material generates acoustic wave. In this paper, piezoelectric transducer detects ultrasonic waveforms. We have experimented in low laser energy for nondestructive evaluation. And theoretical waveform is compared with experimental waveform. And longitudinal, shear wave are detected and their sound velocity are obtained exactly. Also, in application, we discussed how flaw detection might be achieved with laser-generated ultrasound in aluminum plate with drill hole.

  2. Assessment of Foot Trajectory for Human Gait Phase Detection Using Wireless Ultrasonic Sensor Network.

    Science.gov (United States)

    Qi, Yongbin; Soh, Cheong Boon; Gunawan, Erry; Low, Kay-Soon; Thomas, Rijil

    2016-01-01

    This paper presents a new highly accurate gait phase detection system using wearable wireless ultrasonic sensors, which can be used in gait analysis or rehabilitation applications. The gait phase detection system uses the foot displacement information during walking to extract the following gait phases: heel-strike, heel-off, toe-off, and mid-swing. The displacement of foot-mounted ultrasonic sensor is obtained from several passive anchors placed at known locations by employing local spherical positioning technique, which is further enhanced by the combination of recursive Newton-Gauss method and Kalman Filter. The algorithm performance is examined by comparing with a commercial optical motion tracking system with ten healthy subjects and two foot injured subjects. Accurate estimates of gait cycle (with an error of -0.02 ±0.01 s), stance phase(with an error of 0.04±0.03 s), and swing phase (with an error of -0.05±0.03 s) compared to the reference system are obtained. We have also investigated the influence of walking velocities on the performance of the proposed gait phase detection algorithm. Statistical analysis shows that there is no significant difference between both systems during different walking speeds. Moreover, we have tested and discussed the possibility of the proposed system for clinical applications by analyzing the experimental results for both healthy and injured subjects. The experiments show that the estimated gait phases have the potential to become indicators for sports and rehabilitation engineering. PMID:25769165

  3. Ultrasonics crack-detection in demanding pipeline environments and low diameter pipes

    Energy Technology Data Exchange (ETDEWEB)

    Baumeister, Marc; Bouaoua, Nourreddine; Woltermann, Frank; Hennig, Thomas; Berlekamp, Maria; Beuker, Thomas [RTRC, Lingen (Germany)

    2010-07-01

    Building ultrasonic crack-detection tools presents special challenges when conditions are demanding, for example with temperatures above 70 degree C, high pressures exceeding 100 bars, and medium types such as heavy crude oil with inherently high damping and temperature dependency of the damping characteristic, where complications are mainly related to the bonding conditions. Lower pipeline diameters increase the degree of complexity even more. This paper describes the design and development approach chosen by ROSEN for pipelines with an outer diameter ranging from 6 to 8 inches where all the above mentioned issues are also considered. The aim of this tool is the detection of circumferential cracks in the influencing region of the girth weld. The tool body design chosen was that the UT crack detection probes were attached to the central pipe of the ILI tool; this minimized the influence of the welds on run behaviour.

  4. In-Process Detection of Weld Defects Using Laser-Based Ultrasonic Lamb Waves

    Energy Technology Data Exchange (ETDEWEB)

    Kercel, S W

    2001-01-04

    Laser-based ultrasonic (LBU) measurement shows great promise for on-line monitoring of weld quality in tailor-welded blanks. Tailor-welded blanks are steel blanks made from plates of differing thickness and/or properties butt-welded together; they are used in automobile manufacturing to produce body, frame, and closure panels. LBU uses a pulsed laser to generate the ultrasound and a continuous wave (CW) laser interferometer to detect the ultrasound at the point of interrogation to perform ultrasonic inspection. LBU enables in-process measurements since there is no sensor contact or near-contact with the workpiece. The authors have used laser-generated plate (Lamb) waves to propagate from one plate into the weld nugget as a means of detecting defects. This report recounts an investigation of a number of inspection architectures based on processing of signals from selected plate waves, which are either reflected from or transmitted through the weld zone. Bayesian parameter estimation and wavelet analysis (both continuous and discrete) have shown that the LBU time-series signal is readily separable into components that provide distinguishing features, which describe weld quality. The authors anticipate that, in an on-line industrial application, these measurements can be implemented just downstream from the weld cell. Then the weld quality data can be fed back to control critical weld parameters or alert the operator of a problem requiring maintenance. Internal weld defects and deviations from the desired surface profile can then be corrected before defective parts are produced. The major conclusions of this study are as follows. Bayesian parameter estimation is able to separate entangled Lamb wave modes. Pattern recognition algorithms applied to Lamb mode features have produced robust features for distinguishing between several types of weld defects. In other words, the information is present in the output of the laser ultrasonic hardware, and it is feasible to

  5. Influence of scattering phenomena on the solar zenith angle dependence of in-water irradiance levels

    International Nuclear Information System (INIS)

    A Monte Carlo analysis is utilized to determine the influence of the inherent properties of a water mass on the solar zenith angle dependence of subsurface irradiance levels. It is shown that the proportion of scattering interactions (as represented by the scattering albedo ω) has a greater influence on this dependence that does the backscattering probability B. Several representations of direct and/or diffuse incident radiation are considered, and their effects on the solar zenith angle dependence are evaluated. Irradiance level data collected in Lake Erie are compared to the predictions of the Monte Carlo analysis

  6. Capacitive micromachined ultrasonic transducers with diffraction-based integrated optical displacement detection.

    Science.gov (United States)

    Hall, Neal A; Lee, Wook; Degertekin, F Levent

    2003-11-01

    Capacitive detection limits the performance of capacitive micromachined ultrasonic transducers (CMUTs) by providing poor sensitivity below megahertz frequencies and limiting acoustic power output by imposing constraints on the membrane-substrate gap height. In this paper, an integrated optical interferometric detection method for CMUTs, which provides high displacement sensitivity independent of operation frequency and device capacitance, is reported. The method also enables optoelectronics integration in a small volume and provides optoelectronic isolation between transmit and receive electronics. Implementation of the method involves fabricating CMUTs on transparent substrates and shaping the electrode under each individual CMUT membrane in the form of an optical diffraction grating. Each CMUT membrane thus forms a phase-sensitive optical diffraction grating structure that is used to measure membrane displacements down to 2 x 10(-4) A/square root(Hz) level in the dc to 2-MHz range. Test devices are fabricated on quartz substrates, and ultrasonic array imaging in air is performed using a single 4-mm square CMUT consisting of 19 x 19 array of membranes operating at 750 kHz. PMID:14682641

  7. Bond Graph Modelling for Fault Detection and Isolation of an Ultrasonic Linear Motor

    Directory of Open Access Journals (Sweden)

    Mabrouk KHEMLICHE

    2010-12-01

    Full Text Available In this paper Bond Graph modeling, simulation and monitoring of ultrasonic linear motors are presented. Only the vibration of piezoelectric ceramics and stator will be taken into account. Contact problems between stator and rotor are not treated here. So, standing and travelling waves will be briefly presented since the majority of the motors use another wave type to generate the stator vibration and thus obtain the elliptic trajectory of the points on the surface of the stator in the first time. Then, electric equivalent circuit will be presented with the aim for giving a general idea of another way of graphical modelling of the vibrator introduced and developed. The simulations of an ultrasonic linear motor are then performed and experimental results on a prototype built at the laboratory are presented. Finally, validation of the Bond Graph method for modelling is carried out, comparing both simulation and experiment results. This paper describes the application of the FDI approach to an electrical system. We demonstrate the FDI effectiveness with real data collected from our automotive test. We introduce the analysis of the problem involved in the faults localization in this process. We propose a method of fault detection applied to the diagnosis and to determine the gravity of a detected fault. We show the possibilities of application of the new approaches to the complex system control.

  8. Ultrasonic flaw detection of austenitic stainless steel longitudinally welded pipe and tubing

    International Nuclear Information System (INIS)

    Recently there has been the trend that the welded austenitic stainless steel pipe and tubing are used in the nuclear industry in place of the seamless pipe and tubing. For most of the nuclear components, the pipe and tubing must be examined with ultrasonic method by the demands of ASME SA-655. But the ultrasonic flaw detection of the austenitic welds is generally difficult because of scattering and deflection of the acoustic beam due to the coarse grained and elastically anisotropic preferred oriented structure of dendrite. For the thinner welds of pipe and tubing, the attenuation and deflection of the beam do not make the serious problems, however, the deterioration of the signal-to-noise ratio by the coherent structural noise from the welds may still disturb the flaw detection. The longitudinal wave can be employed to suppress the structural noise. This depends upon its longer wave length. In the automatic examination of the pipe and tubing, however, the customary shear wave angle beam technique must be applied to use the skipped beam

  9. A Study on Advanced Ultrasonic Technique for Thermal Fatigue Crack Detection of Thermal Stratification Pipeline in NPPs

    International Nuclear Information System (INIS)

    Ultrasonic inspection techniques are widely used to ensure the reliable operation and lifetime extension of nuclear power plants. Thermal stratification typically occurs in the surge line or the main feed water lines in nuclear power plants. Thermal stratification is a flow condition in which hotter fluid flows over a colder region of fluid in pipeline. Since a change in temperature causes a change in the density of the pipe wall, these thermal conditions might lead to increased overall bending stresses in pipelines. In addition, cyclic changes in stratification height cause thermal stress. This cycling can lead to thermal fatigue crack initiation and crack growth. If thermal fatigue crack grows continuously, the leakage of water or steam will occur and this may cause serious problems on reactor cooling system. Therefore, these cracks must be detected before the crack growth reaches for leakage. In this study, an ultrasonic technique was employed for evaluation of thermal fatigue cracks due to thermal stratification in pipelines of nuclear power plants. The angle beam ultrasonic techniques(time-of-flight diffraction(TOFD) and shadow effect method) were used to detect thermal fatigue cracks which grow from the inner surface of the pipeline. The angle beam ultrasonic technique is usually used for the detection of cracks on the inside of the structures. When ultrasonic waves generated from the angle probe encounters a crack, ultrasonic waves of the shear modes are reflect or transmit from the crack wall. Also ultrasonic waves generated from the angle probe shear modes are diffracted from the tip of the crack, and the shear wave is reflected from the corner of the crack

  10. Parametric Study of the Device Angle Dependency of a Single Vortex Generator on a Flat Plate

    DEFF Research Database (Denmark)

    Fernandez, U.; Réthoré, Pierre-Elouan; Sørensen, Niels N.; Velte, Clara Marika; Zahle, Frederik; Egusquiza, E.

    A detailed study of the device angle dependency of a single vortex generator (VG) is presented in this paper. A single Vortex Generator on a test section wall case, with four different positions of the device angle to the incoming flow, has been designed and solved by computational methods. The...

  11. On the Origin of the Trigger-Angle Dependence of the Ridge Structure

    CERN Document Server

    Hama, Yogiro; Grassi, Frederique; Qian, Wei-Liang

    2012-01-01

    The origin of the trigger-angle dependence of the ridge structure in two-hadron long-range correlations, as observed at RHIC, is discussed as due to an interplay between the elliptic flow caused by the initial state global geometry and flow produced by fluctuations.

  12. Application of ultrasonic signature analysis for fatigue detection in complex structures

    Science.gov (United States)

    Zuckerwar, A. J.

    1974-01-01

    Ultrasonic signature analysis shows promise of being a singularly well-suited method for detecting fatigue in structures as complex as aircraft. The method employs instrumentation centered about a Fourier analyzer system, which features analog-to-digital conversion, digital data processing, and digital display of cross-correlation functions and cross-spectra. These features are essential to the analysis of ultrasonic signatures according to the procedure described here. In order to establish the feasibility of the method, the initial experiments were confined to simple plates with simulated and fatigue-induced defects respectively. In the first test the signature proved sensitive to the size of a small hole drilled into the plate. In the second test, performed on a series of fatigue-loaded plates, the signature proved capable of indicating both the initial appearance and subsequent growth of a fatigue crack. In view of these encouraging results it is concluded that the method has reached a sufficiently advanced stage of development to warrant application to small-scale structures or even actual aircraft.

  13. Sparse Array Imaging of Change-Detected Ultrasonic Signals by Minimum Variance Processing

    Science.gov (United States)

    Michaels, J. E.; Hall, J. S.; Hickman, G.; Krolik, J.

    2009-03-01

    Spatially distributed arrays of permanently attached ultrasonic sensors are being considered for structural health monitoring systems. Most algorithms for analyzing the received signals are based upon change detection whereby baselines from the undamaged structure are subtracted from current signals of interest, and the residual signals are analyzed. In particular, delay-and-sum algorithms applied to the residual signals have been shown to be effective for imaging damage in plate-like structures that support propagation of guided waves. Here we consider minimum variance processing of the residual signals, which is an adaptive beamforming method in common use for processing of radar signals where the weights are adjusted at each pixel location prior to summation based upon actual and expected signal amplitudes. Experimental results from a sparse sensor array show that this processing method can provide a significantly improved signal-to-noise ratio by suppressing unwanted sidelobes in the image.

  14. Fast recognition algorithm of underwater micro-terrain based on ultrasonic detection

    Institute of Scientific and Technical Information of China (English)

    LUO Bo-wen; ZHOU Zhi-jin; BU Ying-yong; ZHAO Hai-ming

    2008-01-01

    An algorithm was proposed to fast recognize three types of underwater micro-terrain, i.e. the level, the gradient and the uneven. With pendulum single beam bathymeter, the hard level concrete floor, the random uneven floor and the gradient wood panel (8°) were ultrasonically detected 20 times, respectively. The results show that the algorithm is right from fact that the first clustering values of the uneven are all less than the threshold value of 60.0% that is obtained by the level and gradient samples. The algorithm based on the dynamic clustering theory can effectively eliminate the influences of the exceptional elevation values produced by the disturbances resulted from the grazing angle, the characteristic of bottom material and environmental noises, and its real-time capability is good. Thus, the algorithm provides a foundation for the next restructuring of the micro-terrain.

  15. A model for the ultrasonic detection of surface-breaking cracks by the scanning laser source technique

    OpenAIRE

    Arias Vicente, Irene; Achenbach, J. D.

    2004-01-01

    A model for the scanning laser source (SLS) technique is presented. The SLS is a novel laser-based inspection method for the ultrasonic detection of small surface-breaking cracks. The generated ultrasonic signal is monitored as a line-focused laser is scanned over the defect. Characteristic changes in the amplitude and the frequency content are observed. The modeling approach is based on the decomposition of the field generated by the laser in a cracked two-dimensional half-space, by virtue o...

  16. Ultrasonic waves scattering through dissimilar welds: application to characterisation of spurious echoes detected during inspection

    International Nuclear Information System (INIS)

    Ultrasonic testing of bimetallic welds can show the presence of structural echoes. In pulse echo mode inspections at oblique incidence, these echoes are detected close to the back-wall (surface opposite to the control). These echoes have a specific shape: the amplitude is distributed along lines parallel to the weld sides. Such echoes can disturb the inspection: they can be misinterpreted as provided by a defect, or they can mask a possible defect. The aim of this thesis is to explain this phenomenon with an interpretation based on the anisotropic property of the weld. In such a structure, specific mode conversions in the lasts welding pass arise. Mode converted waves can reflect normally on the back-wall and therefore back propagate to the transducer along the same wave path as the forward propagation. Some generalities of ultrasonic testing of bimetallic welds are given in a preliminary chapter. In the first chapter, various experiments showed that these structural echoes do not result from beam deflection in the weld and that this phenomenon occurs in the last millimeters under the back-wall. According to these results, an interpretation for these echoes based on the anisotropic and the inhomogeneous structure of the weld is given in the last welding pass, oblique compression waves may be converted into normal shear waves. The second chapter presented a theoretical analysis of these mode conversions phenomenon between two metallurgical structures with different dendrite orientations. The analysis of the welding passes metallography and a bibliographic study summarizes on the relevancy to use a orthotropic symmetry to describe the metallurgical structure of the material under test. The third chapter deals with experimental studies to confirm this hypothesis. Detection of shear waves in the last welding passes near the back-wall mock-up using a specific sensor, able to discriminate the polarisation wave at the reception, validate the mode conversion hypothesis

  17. Ultrasonic sensing of GMAW: Laser/EMAT defect detection system. [Gas Metal Arc Welding (GMAW), Electromagnetic acoustic transducer (EMAT)

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, N.M.; Johnson, J.A.; Larsen, E.D. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Van Clark, A. Jr.; Schaps, S.R.; Fortunko, C.M. (National Inst. of Standards and Technology, Boulder, CO (United States))

    1992-01-01

    In-process ultrasonic sensing of welding allows detection of weld defects in real time. A noncontacting ultrasonic system is being developed to operate in a production environment. The principal components are a pulsed laser for ultrasound generation and an electromagnetic acoustic transducer (EMAT) for ultrasound reception. A PC-based data acquisition system determines the quality of the weld on a pass-by-pass basis. The laser/EMAT system interrogates the area in the weld volume where defects are most likely to occur. This area of interest is identified by computer calculations on a pass-by-pass basis using weld planning information provided by the off-line programmer. The absence of a signal above the threshold level in the computer-calculated time interval indicates a disruption of the sound path by a defect. The ultrasonic sensor system then provides an input signal to the weld controller about the defect condition. 8 refs.

  18. Multivariate data-driven modelling and pattern recognition for damage detection and identification for acoustic emission and acousto-ultrasonics

    International Nuclear Information System (INIS)

    Different methods are commonly used for non-destructive testing in structures; among others, acoustic emission and ultrasonic inspections are widely used to assess structures. The research presented in this paper is motivated by the need to improve the inspection capabilities and reliability of structural health monitoring (SHM) systems based on ultrasonic guided waves with focus on the acoustic emission and acousto-ultrasonics techniques. The use of a guided wave based approach is driven by the fact that these waves are able to propagate over relatively long distances, and interact sensitively and uniquely with different types of defect. Special attention is paid here to the development of efficient SHM methodologies. This requires robust signal processing techniques for the correct interpretation of the complex ultrasonic waves. Therefore, a variety of existing algorithms for signal processing and pattern recognition are evaluated and integrated into the different proposed methodologies. As a contribution to solve the problem, this paper presents results in damage detection and classification using a methodology based on hierarchical nonlinear principal component analysis, square prediction measurements and self-organizing maps, which are applied to data from acoustic emission tests and acousto-ultrasonic inspections. At the end, the efficiency of these methodologies is experimentally evaluated in diverse anisotropic composite structures. (paper)

  19. Aspect angle dependence of backscatter intensity of 1-m auroral plasma waves

    International Nuclear Information System (INIS)

    The backscatter intensities of primary and secondary 1-m unstable plasma waves in the auroral E region have been measured as a function of magnetic aspect angle (α) for electric field values between 25 and 30 mV/m. The variation of the absorption A, measured in decibels, is of the form A = -IaCo cos2 α/(1 + Co cos2 α). The best fits to the observed attenuation yield parameter values of (Ia, Co) = (49.6, 530) and (48.8, 900) for primary and secondary waves, respectively. The backscatter intensity from primary waves has the same aspect angle dependence as the mean Doppler velocity aspect angle-dependence observed in previous auroral radar data sets (Nielsen, 1986). The observations suggest that the radar backscatter cross section of the primary waves maximizes a few kilometers higher in altitude than that of the secondary waves

  20. SU-E-T-195: Gantry Angle Dependency of MLC Leaf Position Error

    International Nuclear Information System (INIS)

    Purpose: The aim of this study was to investigate the gantry angle dependency of the multileaf collimator (MLC) leaf position error. Methods: An automatic MLC quality assurance system (AutoMLCQA) was developed to evaluate the gantry angle dependency of the MLC leaf position error using an electronic portal imaging device (EPID). To eliminate the EPID position error due to gantry rotation, we designed a reference maker (RM) that could be inserted into the wedge mount. After setting up the EPID, a reference image was taken of the RM using an open field. Next, an EPID-based picket-fence test (PFT) was performed without the RM. These procedures were repeated at every 45° intervals of the gantry angle. A total of eight reference images and PFT image sets were analyzed using in-house software. The average MLC leaf position error was calculated at five pickets (-10, -5, 0, 5, and 10 cm) in accordance with general PFT guidelines using in-house software. This test was carried out for four linear accelerators. Results: The average MLC leaf position errors were within the set criterion of <1 mm (actual errors ranged from -0.7 to 0.8 mm) for all gantry angles, but significant gantry angle dependency was observed in all machines. The error was smaller at a gantry angle of 0° but increased toward the positive direction with gantry angle increments in the clockwise direction. The error reached a maximum value at a gantry angle of 90° and then gradually decreased until 180°. In the counter-clockwise rotation of the gantry, the same pattern of error was observed but the error increased in the negative direction. Conclusion: The AutoMLCQA system was useful to evaluate the MLC leaf position error for various gantry angles without the EPID position error. The Gantry angle dependency should be considered during MLC leaf position error analysis

  1. SU-E-T-195: Gantry Angle Dependency of MLC Leaf Position Error

    Energy Technology Data Exchange (ETDEWEB)

    Ju, S; Hong, C; Kim, M; Chung, K; Kim, J; Han, Y; Ahn, S; Chung, S; Shin, E; Shin, J; Kim, H; Kim, D; Choi, D [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2014-06-01

    Purpose: The aim of this study was to investigate the gantry angle dependency of the multileaf collimator (MLC) leaf position error. Methods: An automatic MLC quality assurance system (AutoMLCQA) was developed to evaluate the gantry angle dependency of the MLC leaf position error using an electronic portal imaging device (EPID). To eliminate the EPID position error due to gantry rotation, we designed a reference maker (RM) that could be inserted into the wedge mount. After setting up the EPID, a reference image was taken of the RM using an open field. Next, an EPID-based picket-fence test (PFT) was performed without the RM. These procedures were repeated at every 45° intervals of the gantry angle. A total of eight reference images and PFT image sets were analyzed using in-house software. The average MLC leaf position error was calculated at five pickets (-10, -5, 0, 5, and 10 cm) in accordance with general PFT guidelines using in-house software. This test was carried out for four linear accelerators. Results: The average MLC leaf position errors were within the set criterion of <1 mm (actual errors ranged from -0.7 to 0.8 mm) for all gantry angles, but significant gantry angle dependency was observed in all machines. The error was smaller at a gantry angle of 0° but increased toward the positive direction with gantry angle increments in the clockwise direction. The error reached a maximum value at a gantry angle of 90° and then gradually decreased until 180°. In the counter-clockwise rotation of the gantry, the same pattern of error was observed but the error increased in the negative direction. Conclusion: The AutoMLCQA system was useful to evaluate the MLC leaf position error for various gantry angles without the EPID position error. The Gantry angle dependency should be considered during MLC leaf position error analysis.

  2. Fracture detection in crystalline rock using ultrasonic reflection techniques: Volume 1

    International Nuclear Information System (INIS)

    This research was initiated to investigate using ultrasonic seismic reflection techniques to detect fracture discontinuities in a granitic rock. Initial compressional (P) and shear (SH) wave experiments were performed on a 0.9 x 0.9 x 0.3 meter granite slab in an attempt to detect seismic energy reflected from the opposite face of the slab. It was found that processing techniques such as deconvolution and array synthesis could improve the standout of the reflection event. During the summers of 1979 and 1980 SH reflection experiments were performed at a granite quarry near Knowles, California. The purpose of this study was to use SH reflection methods to detect an in situ fracture located one to three meters behind the quarry face. These SH data were later analyzed using methods similar to those applied in the laboratory. Interpretation of the later-arriving events observed in the SH field data as reflections from a steeply-dipping fracture was inconclusive. 41 refs., 43 figs., 7 tabs

  3. Quantitative detection of cerebral arteriosclerosis by means of the Doppler ultrasonic technique.

    Science.gov (United States)

    Miyazaki, M

    1986-01-01

    A correlation between the continuity of the cerebral blood flow pattern and the cerebral vascular resistance (namely, cerebral arteriosclerosis) was investigated by the Doppler ultrasonic technique. The following facts were observed. Examination of the brachial blood flow pattern in circulatory stress, i.e., hand-grasping, brachial-binding, cold- and warm-stimulating tests revealed that the more the peripheral vascular resistance was increased, the more was the discontinuity of brachial blood flow pattern increased. Investigation of the continuity of the cerebral blood flow pattern (internal carotid artery) in 18 young healthy persons and 46 elderly patients with cerebral vascular diseases revealed a continuous pattern in all of the young persons, while the discontinuous pattern was frequently observed in the elderly patients. These findings suggest that the cerebral vascular resistance is more increased in the elderly patients than in the young persons. The cerebral blood flow pattern was classified into the following three types according to the continuity of the cerebral blood flow pattern: continuous, intermediate and discontinuous type, and the relation to the Continuous Index (CI), which was devised as an objective parameter of the continuity, was examined. The following CI figures were obtained: 110-200% in the young persons; in the elderly patients: continuous type, 120-185%; intermediate type, 85-135%; discontinuous type, 50-85%. From the above findings it is postulated that the Doppler ultrasonic technique is useful for the quantitative detection of cerebral arteriosclerosis, i.e., anticipation of cerebral vascular accidents, and for the discrimination between arteriosclerotic dementia and Alzheimer's disease. PMID:3525327

  4. The detection of cavitation in hydraulic machines by use of ultrasonic signal analysis

    Science.gov (United States)

    Gruber, P.; Odermatt, P.; Etterlin, M.; Lerch, T.; Frei, M.; Farhat, M.

    2014-03-01

    This presentation describes an experimental approach for the detection of cavitation in hydraulic machines by use of ultrasonic signal analysis. Instead of using the high frequency pulses (typically 1MHz) only for transit time measurement different other signal characteristics are extracted from the individual signals and its correlation function with reference signals in order to gain knowledge of the water conditions. As the pulse repetition rate is high (typically 100Hz), statistical parameters can be extracted of the signals. The idea is to find patterns in the parameters by a classifier that can distinguish between the different water states. This classification scheme has been applied to different cavitation sections: a sphere in a water flow in circular tube at the HSLU in Lucerne, a NACA profile in a cavitation tunnel and a Francis model test turbine both at LMH in Lausanne. From the signal raw data several statistical parameters in the time and frequency domain as well as from the correlation function with reference signals have been determined. As classifiers two methods were used: neural feed forward networks and decision trees. For both classification methods realizations with lowest complexity as possible are of special interest. It is shown that three signal characteristics, two from the signal itself and one from the correlation function are in many cases sufficient for the detection capability. The final goal is to combine these results with operating point, vibration, acoustic emission and dynamic pressure information such that a distinction between dangerous and not dangerous cavitation is possible.

  5. The detection of cavitation in hydraulic machines by use of ultrasonic signal analysis

    International Nuclear Information System (INIS)

    This presentation describes an experimental approach for the detection of cavitation in hydraulic machines by use of ultrasonic signal analysis. Instead of using the high frequency pulses (typically 1MHz) only for transit time measurement different other signal characteristics are extracted from the individual signals and its correlation function with reference signals in order to gain knowledge of the water conditions. As the pulse repetition rate is high (typically 100Hz), statistical parameters can be extracted of the signals. The idea is to find patterns in the parameters by a classifier that can distinguish between the different water states. This classification scheme has been applied to different cavitation sections: a sphere in a water flow in circular tube at the HSLU in Lucerne, a NACA profile in a cavitation tunnel and a Francis model test turbine both at LMH in Lausanne. From the signal raw data several statistical parameters in the time and frequency domain as well as from the correlation function with reference signals have been determined. As classifiers two methods were used: neural feed forward networks and decision trees. For both classification methods realizations with lowest complexity as possible are of special interest. It is shown that three signal characteristics, two from the signal itself and one from the correlation function are in many cases sufficient for the detection capability. The final goal is to combine these results with operating point, vibration, acoustic emission and dynamic pressure information such that a distinction between dangerous and not dangerous cavitation is possible

  6. In-Line Crack and Stress Detection in Silicon Solar Cells Using Resonance Ultrasonic Vibrations

    Energy Technology Data Exchange (ETDEWEB)

    Ostapenko, Sergei

    2013-04-03

    Statement of Problem and Objectives. Wafer breakage in automated solar cell production lines is identified as a major technical problem and a barrier for further cost reduction of silicon solar module manufacturing. To the best of our knowledge, there are no commercial systems addressing critical needs for in-line inspection of the mechanical quality of solar wafers and cells. The principal objective of the SBIR program is to validate through experiments and computer modeling the applicability of the Resonance Ultrasonic Vibrations system, which ultimately can be used as a real-time in-line manufacturing quality control tool for fast detection of mechanically unstable silicon solar cells caused by cracks. The specific objective of Phase II is to move the technology of in-line crack detection from the laboratory level to commercial demonstration through development of a system prototype. The fragility of silicon wafers possessing low mechanical strength is attributed to peripheral and bulk millimeter-length cracks. The research program is based on feasibility results obtained during Phase I, which established that: (i) the Resonance Ultrasonic Vibrations method is applicable to as-cut, processed wafers and finished cells; (ii) the method sensitivity depends on the specific processing step; it is highest in as-cut wafers and lowest in wafers with metallization pattern and grid contacts; (iii) the system is capable of matching the 2.0 seconds per wafer throughput rate of state-of-art solar cell production lines; (iv) finite element modeling provides vibration mode analysis along with peak shift versus crack length and crack location dependence; (v) a high 91% crack rejection rate was confirmed through experimentation and statistical analysis. The Phase II project has the following specific tasks: (i) specify optimal configurations of the in-line system’s component hardware and software; (ii) develop and justify a system prototype that meets

  7. Signal Processing Variables for Optimization of Flaw Detection in Composites Using Ultrasonic Guided Wave Scanning

    Science.gov (United States)

    Roth, Don J.; Cosgriff, Laura M.; Martin, Richard E.; Teemer, LeTarrie

    2004-01-01

    This study analyzes the effect of signal processing variables on the ability of the ultrasonic guided wave scan method at NASA Glenn Research Center to distinguish various flaw conditions in ceramic matrix composites samples. In the ultrasonic guided wave scan method, several time- and frequency-domain parameters are calculated from the ultrasonic guided wave signal at each scan location to form images. The parameters include power spectral density, centroid mean time, total energy (zeroth moment), centroid frequency, and ultrasonic decay rate. A number of signal processing variables are available to the user when calculating these parameters. These signal processing variables include 1) the time portion of the time-domain waveform processed, 2) integration type for the properties requiring integrations, 3) bounded versus unbounded integrations, 4) power spectral density window type, 5) and the number of time segments chosen if using the short-time fourier transform to calculate ultrasonic decay rate. Flaw conditions examined included delamination, cracking, and density variation.

  8. Defect detection performance of the UCSD non-contact air-coupled ultrasonic guided wave inspection of rails prototype

    Science.gov (United States)

    Mariani, Stefano; Nguyen, Thompson V.; Sternini, Simone; Lanza di Scalea, Francesco; Fateh, Mahmood; Wilson, Robert

    2016-04-01

    The University of California at San Diego (UCSD), under a Federal Railroad Administration (FRA) Office of Research and Development (R&D) grant, is developing a system for high-speed and non-contact rail defect detection. A prototype using an ultrasonic air-coupled guided wave signal generation and air-coupled signal detection, paired with a real-time statistical analysis algorithm, has been realized. This system requires a specialized filtering approach based on electrical impedance matching due to the inherently poor signal-to-noise ratio of air-coupled ultrasonic measurements in rail steel. Various aspects of the prototype have been designed with the aid of numerical analyses. In particular, simulations of ultrasonic guided wave propagation in rails have been performed using a Local Interaction Simulation Approach (LISA) algorithm. The system's operating parameters were selected based on Receiver Operating Characteristic (ROC) curves, which provide a quantitative manner to evaluate different detection performances based on the trade-off between detection rate and false positive rate. The prototype based on this technology was tested in October 2014 at the Transportation Technology Center (TTC) in Pueblo, Colorado, and again in November 2015 after incorporating changes based on lessons learned. Results from the 2015 field test are discussed in this paper.

  9. T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

    OpenAIRE

    Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Kaneshiro, Kayleigh; Schwarzkopf, Ran; Hara, Takeshi; Yoshioka, Hiroshi

    2015-01-01

    Objectives To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. Methods T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and an...

  10. Evaluation of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station

    International Nuclear Information System (INIS)

    During a recent inservice inspection (ISI) of a dissimilar metal weld (DMW) in an inlet (hot leg) steam generator nozzle at North Anna Power Station Unit 1, several axially oriented flaws went undetected by the licensee's manual ultrasonic testing (UT) technique. The flaws were subsequently detected as a result of outside diameter (OD) surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the DMW. Further ultrasonic tests were then performed, and a total of five axially oriented flaws, classified as primary water stress corrosion cracking (PWSCC), were detected in varied locations around the weld circumference.

  11. Determination of selected polychlorinated biphenyls in soil by miniaturised ultrasonic solvent extraction and gas chromatography-mass-selective detection

    International Nuclear Information System (INIS)

    Miniaturised ultrasonic solvent extraction procedure was developed for the determination of selected polychlorinated biphenyls (PCBs) in soil samples by gas chromatography-mass-selective detection by using 23 factorial experimental design. Recoveries of PCBs from fortified soil samples are over 90% for three different fortification levels between 40 and 120 μg kg-1, and relative standard deviations of the recoveries are below 7%. The limits of detection (LODs) ranged from 0.003 to 0.006 μg kg-1. The performance of the proposed method was compared to traditional shake flask extraction method on the spiked real soil sample and extraction methods showed comparable efficiencies. Proposed miniaturised ultrasonic solvent extraction offers several advantages, i.e., reducing sample requirement for measurement of target compound, less solvent consumption and reducing the costs associated with solvent purchase and waste disposal

  12. Detection of surface breaking cracks in centrifugally cast stainless steel with ultrasonic inspection from the cracked side

    International Nuclear Information System (INIS)

    The ability of detecting surface breaking or near-surface cracks with ultrasonic techniques from the inside of centrifugally cast stainless steel pipes have been investigated by The Swedish Plant Inspectorate and AF-Teknisk Roentgencentralen AB on behalf of The Swedish Nuclear Power Inspectorate and The Swedish State Power Board. Fifteen specimens from the international Stainless Steel Round Robin Test were used in this study. All specimens were examined from the cracked side with different ultrasonic probes. The data reported here indicate that a probe with dual elements, low frequency, longitudinal waves and short focus distance can detect almost all of the intended defects with a rather good signal-to-noise ratio. (author)

  13. Future Constraints on Angle-Dependent Non-Gaussianity from Large Radio Surveys

    CERN Document Server

    Raccanelli, Alvise; Bartolo, Nicola; Bertacca, Daniele; Liguori, Michele; Matarrese, Sabino; Norris, Ray P; Parkinson, David

    2015-01-01

    We investigate how well future large-scale radio surveys could measure different shapes of primordial non-Gaussianity; in particular we focus on angle-dependent non-Gaussianity arising from primordial anisotropic sources, whose bispectrum has an angle dependence between the three wavevectors that is characterized by Legendre polynomials $\\mathcal{P}_L$ and expansion coefficients $c_L$. We provide forecasts for measurements of galaxy power spectrum, finding that Large-Scale Structure (LSS) data could allow measurements of primordial non-Gaussianity competitive or improving upon current constraints set by CMB experiments, for all the shapes considered. We argue that the best constraints will come from the possibility to assign redshift information to radio galaxy surveys, and investigate a few possible scenarios for the EMU and SKA surveys. A realistic (futuristic) modeling could provide constraints of $f_{\\rm NL}^{\\rm loc} \\approx 1 (0.5)$ for the local shape, $f_{\\rm NL}$ of $\\mathcal{O}(10) (\\mathcal{O}(1))$...

  14. The In-Plane Anisotropy of WTe2 Investigated by Angle-Dependent and Polarized Raman Spectroscopy.

    Science.gov (United States)

    Song, Qingjun; Pan, Xingchen; Wang, Haifeng; Zhang, Kun; Tan, Qinghai; Li, Pan; Wan, Yi; Wang, Yilun; Xu, Xiaolong; Lin, Miaoling; Wan, Xiangang; Song, Fengqi; Dai, Lun

    2016-01-01

    Tungsten ditelluride (WTe2) is a semi-metallic layered transition metal dichalcogenide with a stable distorted 1T phase. The reduced symmetry of this system leads to in-plane anisotropy in various materials properties. We have systemically studied the in-plane anisotropy of Raman modes in few-layer and bulk WTe2 by angle-dependent and polarized Raman spectroscopy (ADPRS). Ten Raman modes are clearly resolved. Their intensities show periodic variation with sample rotating. We identify the symmetries of the detected modes by quantitatively analyzing the ADPRS results based on the symmetry selection rules. Material absorption effect on the phonon modes with high vibration frequencies is investigated by considering complex Raman tensor elements. We also provide a rapid and nondestructive method to identify the crystallographic orientation of WTe2. The crystallographic orientation is further confirmed by the quantitative atomic-resolution force image. Finally, we find that the atomic vibrational tendency and complexity of detected modes are also reflected in the shrinkage degree defined based on ADPRS, which is confirmed by corresponding density functional calculation. Our work provides a deep understanding of the interaction between WTe2 and light, which will benefit in future studies about the anisotropic physical properties of WTe2 and other in-plane anisotropic materials. PMID:27404226

  15. Detection of Boundaries of Carotid Arterial Wall by Analyzing Ultrasonic RF Signals

    Science.gov (United States)

    Ibrahim, Nabilah; Hasegawa, Hideyuki; Kanai, Hiroshi

    2012-07-01

    In line with the fact that the intima-media thickness (IMT) of the carotid arterial wall is the most frequently used indicator to diagnose atherosclerosis by ultrasound, it is essential to accurately estimate the thickness of the intima-media complex (IMC) boundaries, i.e., the lumen-intima boundary (LIB) and media-adventitia boundary (MAB). In this study, an improved adaptive model of an ultrasonic echo was developed for the model to realize better fitting to the reference RF echo, which is measured from a glass plate, using a Gaussian window for the envelope function of the adaptive model. Using the mean squared error (MSE) method, the envelope of the improved adaptive model (multiply the sinusoidal wave with the Gaussian window) was fitted with the envelope of an RF echo measured in vivo to estimate the boundaries of the carotid arterial wall. Firstly, a computer simulation of the carotid arterial wall was conducted to evaluate the accuracy of boundary detection using the envelope of the improved adaptive model. In the simulation, IMT was set at 0.50 mm in a 7.2-mm-long short segment in the longitudinal direction. The IMT estimated by the proposed method was 0.54 mm. The 8% error between the true and detected IMTs showed the high accuracy of the envelope of the improved adaptive model in boundary detection. In the in vivo measurement, for the 4.8-mm-long short segment in the longitudinal direction, the average IMT automatically estimated by the proposed method was 0.57 mm. The result was compared with those obtained by the previous method and manually. The IMT estimated by the previous method, which uses an RF adaptive model, was 0.59 mm and the manually determined IMT was 0.56 mm. The smaller difference between the results obtained by the proposed method and manually verified that boundary detection by the proposed method was better than that by the previous method.

  16. Non-destructive testing methods for detection of creep-induced defects by means of ultrasonic surface waves

    International Nuclear Information System (INIS)

    A method is presented for measuring the propagation velocity of surface waves in the ultrasonic frequency range. The creep-induced defect occurs predominantly at the topmost surface and leads to a minor deceleration of the ultrasonic waves in the material. With increasing penetration depth, the waves increasingly scan the material layers deeper down from the surface, which are increasingly less damaged. This indicates a smooth increase in the propagation velocity. Initial measurements at two damaged pipe bends, both after service times of more than 200.000 hours, exhibit the predicted behaviour. In both cases, the wave velocity increases at damaged sites with increasing penetration depth. The results obtained are in good agreement with metallographic examinations of the detected defect sites at the pipe bends. (orig./MM)

  17. Converging ultrasonic shear-vertical waves generated by a double-line laser and its application for surface defect detection

    International Nuclear Information System (INIS)

    A double-line laser source as an irradiation pattern for the generation of ultrasonic waves is proposed. Simulated results show that the shear-vertical (SV) waves generated by the double-line laser source superimpose and produce a convergence effect at the center axis with a fixed angle. The amplitude of the converging SV wave is significantly improved compared to the ultrasonic field generated by a single-line source under the same condition of the thermoelastic regime. Simulations show good agreement with experimental results, which demonstrate that the SV waves in a steel plate subjected to the double-line laser source converge efficiently at the center axis. Then, a method using the converging SV to detect surface defect on a steel plate is proposed. The characterization of the surface defect has been quantitatively measured with high accuracy by the well-designed double-line source. (author)

  18. National Metal Casting Research Institute final report. Development of an automated ultrasonic inspection cell for detecting subsurface discontinuities in cast gray iron. Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    Burningham, J.S. [University of Northern Iowa, Cedar Falls, IA (United States). Dept. of Industrial Technology

    1995-08-01

    This inspection cell consisted of an ultrasonic flaw detector, transducer, robot, immersion tank, computer, and software. Normal beam pulse-echo ultrasonic nondestructive testing, using the developed automated cell, was performed on 17 bosses on each rough casting. Ultrasonic transducer selection, initial inspection criteria, and ultrasonic flow detector (UFD) setup parameters were developed for the gray iron castings used in this study. The software were developed for control of the robot and UFD in real time. The software performed two main tasks: emulating the manual operation of the UFD, and evaluating the ultrasonic signatures for detecting subsurface discontinuities. A random lot of 105 castings were tested; the 100 castings that passed were returned to the manufacturer for machining into finished parts and then inspection. The other 5 castings had one boss each with ultrasonic signatures consistent with subsurface discontinuities. The cell was successful in quantifying the ultrasonic echo signatures for the existence of signature characteristics consistent with Go/NoGo criteria developed from simulated defects. Manual inspection showed that no defects in the areas inspected by the automated cell avoided detection in the 100 castings machined into finished parts. Of the 5 bosses found to have subsurface discontinuities, two were verified by manual inspection. The cell correctly classified 1782 of the 1785 bosses (99.832%) inspected.

  19. Magnetic aspect angle dependence of spectra from coherent radio aurora backscatter

    International Nuclear Information System (INIS)

    In 1981, a multiple path radar system was operated on the Canadian prairies with three 50-MHz transmitters and two receivers all separately located such as to establish six backscatter links. The radar beams illuminated the same scatter volume in the ionospheric E layer. Four of these links produced coherent backscatter signals from 3-m wavelength irregularities under different magnetic aspect angles ranging from 1.5 degree to 5.9 degree (reference height 110 km), but under almost identical drift flow angles. The radars were operated in the CW mode which yielded high time and spectral resolution but only moderate spatial resolution. In order to avoid confusion between spectral peaks from different locations within the backscatter volume, only single peaked spectra have been analyzed and compared. The Doppler shifts of both type I and type II spectra exhibit an aspect angle dependence which is much weaker than that predicted by existing linear and nonlinear theories

  20. Plasmonic nanowires arranged in Fibonacci number chain: Excitation angle-dependent optical properties

    Directory of Open Access Journals (Sweden)

    Mohit Raghuwanshi

    2013-02-01

    Full Text Available Herein we numerically study the excitation angle-dependant far-field and near-field optical properties of vertical plasmonic nanowires arranged in an unconventional linear geometry: Fibonacci number chain. The first five numbers in the Fibonacci series (1, 1, 2, 3, 5 were mapped to the size of gold nanowires, and arranged in a linear chain to study their optical interactions, and compared them to conventional chain of vertical gold nanowires. By harnessing the radiative and evanescent coupling regimes in the geometry, we found a systematic variation in the far-field extinction and near-field confinement in the geometries. Our simulation studies revealed enhanced backscattered intensity in the far-field radiation pattern at excitation angles along the chain-length of Fibonacci geometry, which was otherwise absent for conventional chain of plasmonic nanowires. Such angular reconfiguration of optical fields in unconventional linear geometries can be harnessed for tunable on-chip plasmonics.

  1. Incident angle dependence of reactions between graphene and hydrogen atom by molecular dynamics simulation

    CERN Document Server

    Saito, Seiki; Nakamura, Hiroaki

    2009-01-01

    Incident angle dependence of reactions between graphene and hydrogen atoms are obtained qualitatively by classical molecular dynamics simulation under the NVE condition with modified Brenner reactive empirical bond order (REBO) potential. Chemical reaction depends on two parameters, i.e., polar angle $\\theta$ and azimuthal angle $\\phi$ of the incident hydrogen. From the simulation results, it is found that the reaction rates strongly depend on polar angle $\\theta$. Reflection rate becomes larger with increasing $\\theta$, and the $\\theta$ dependence of adsorption rate is also found. The $\\theta$ dependence is caused by three dimensional structure of the small potential barrier which covers adsorption sites. $\\phi$ dependence of penetration rate is also found for large $\\theta$.

  2. Incident-angle dependent color tuning from a single plasmonic chip

    International Nuclear Information System (INIS)

    We report on a broad color tuning effect covering the visible range from a single plasmonic chip. By simply tilting the orientation of the designed plasmonic chip within a certain range, the photon–plasmon coupling interactions between the incident light and the plasmonic nanostructures on the chip can be finely tuned, resulting in an angle-dependent continuous color filtering effect. The physical mechanism of the device is investigated through the full-wave calculations, which provide important guidance for the design and optimization of the proposed devices. The broad color tuning from the demonstrated single chip will potentially benefit visualization and display technologies, and is particularly useful for the construction of reflection-based spatial light modulators. (paper)

  3. View-angle-dependent AIRS Cloudiness and Radiance Variance: Analysis and Interpretation

    Science.gov (United States)

    Gong, Jie; Wu, Dong L.

    2013-01-01

    Upper tropospheric clouds play an important role in the global energy budget and hydrological cycle. Significant view-angle asymmetry has been observed in upper-level tropical clouds derived from eight years of Atmospheric Infrared Sounder (AIRS) 15 um radiances. Here, we find that the asymmetry also exists in the extra-tropics. It is larger during day than that during night, more prominent near elevated terrain, and closely associated with deep convection and wind shear. The cloud radiance variance, a proxy for cloud inhomogeneity, has consistent characteristics of the asymmetry to those in the AIRS cloudiness. The leading causes of the view-dependent cloudiness asymmetry are the local time difference and small-scale organized cloud structures. The local time difference (1-1.5 hr) of upper-level (UL) clouds between two AIRS outermost views can create parts of the observed asymmetry. On the other hand, small-scale tilted and banded structures of the UL clouds can induce about half of the observed view-angle dependent differences in the AIRS cloud radiances and their variances. This estimate is inferred from analogous study using Microwave Humidity Sounder (MHS) radiances observed during the period of time when there were simultaneous measurements at two different view-angles from NOAA-18 and -19 satellites. The existence of tilted cloud structures and asymmetric 15 um and 6.7 um cloud radiances implies that cloud statistics would be view-angle dependent, and should be taken into account in radiative transfer calculations, measurement uncertainty evaluations and cloud climatology investigations. In addition, the momentum forcing in the upper troposphere from tilted clouds is also likely asymmetric, which can affect atmospheric circulation anisotropically.

  4. Detection of hard intermetallics in β-quenched and thermally aged Zircaloy-2 using ultrasonic measurements

    International Nuclear Information System (INIS)

    Zircaloy-2 is widely used for critical core components in the pressurised heavy water reactors. Components of Zircaloy-2 are usually fabricated from the β-quenched billets. Proper quenching treatment must be ensured to avoid the rejection of finished products made from Zircaloy-2. Metallographic techniques are used for this purpose. However, it is advantageous to use nondestructive testing (NDT) techniques such as ultrasonics. In this work, laboratory investigations are carried out on the feasibility for the assessment of the acceptability of the β-quenched microstructure using ultrasonic attenuation and velocity measurements in the frequency range 2-100 MHz. Precise velocity measurements with an accuracy of 0.2 ns by cross-correlation technique have been made in this study. Results indicate that low frequency (2-10 MHz) ultrasonic velocity measurements using both longitudinal and transverse waves are useful for revealing the presence of hard intermetallics. High-frequency (75 and 100 MHz) ultrasonic velocity measurements are useful for revealing the early-stage dissociation of β-quenched martensite to α-phase. Ultrasonic measurements are also correlated with hardness and density measurements in addition to microstructural features. As compared to the attenuation measurements, velocity measurements are more reliable and repeatable for microstructural characterisation of Zircaloy-2. (orig.)

  5. An evaluation of detection ability of ultrasonic testing with a large aperture transducer for axial cracks in cast stainless steel pipe welds

    International Nuclear Information System (INIS)

    Ultrasonic testing is difficult to apply to cast stainless steel which is the material of the main coolant pipes in pressurized water reactors, because of the large attenuation and scattering of ultrasonic waves caused by its macro structure. In this study, ultrasonic testing for progression of axial fatigue cracks of a welded area in the test piece of cast stainless steel pipe was performed using double big-size ultrasonic probes which were formerly developed in INSS. It was found that detection of defects that were over 6% of the target depth for the specimen thickness of 69mm is possible, and detection of defects with over 10% of the target depth is possible for all test conditions. (author)

  6. Characterization of Angle Dependent Color Travel of Printed Multi-Color Effect Pigment on Different Color Substrates

    Directory of Open Access Journals (Sweden)

    Mirica Karlovits

    2015-03-01

    Full Text Available Color-travel pigments, which exhibit much more extensive color change as well provide angle-dependent optical effect can be used in many industrial products. In present paper the multi-color effect pigment printed on three different foils with different background color (black, silver and transparent was investigated. The pigment was based on synthetically produced transparent silicon dioxide platelets coated with titanium dioxide. CIEL*a*b* values and reflection of prints were measured by multi-angle spectrophotometer at constant illumination at an angle of 45º and different viewing angles (-15º, 15°, 25º, 45º, 75º and 110º were used. The measurements of printed multi-color pigment showed that CIEL*a*b* color coordinates varied to great extents, depending on detection angles as well on color of the printing substrate. The study revealed that pigmnet printed on black background obtained significant change in color. The study has also shown that when viewing angle increases, the reflection curves decreases.

  7. Electromagnetic ultrasonic guided waves

    CERN Document Server

    Huang, Songling; Li, Weibin; Wang, Qing

    2016-01-01

    This book introduces the fundamental theory of electromagnetic ultrasonic guided waves, together with its applications. It includes the dispersion characteristics and matching theory of guided waves; the mechanism of production and theoretical model of electromagnetic ultrasonic guided waves; the effect mechanism between guided waves and defects; the simulation method for the entire process of electromagnetic ultrasonic guided wave propagation; electromagnetic ultrasonic thickness measurement; pipeline axial guided wave defect detection; and electromagnetic ultrasonic guided wave detection of gas pipeline cracks. This theory and findings on applications draw on the author’s intensive research over the past eight years. The book can be used for nondestructive testing technology and as an engineering reference work. The specific implementation of the electromagnetic ultrasonic guided wave system presented here will also be of value for other nondestructive test developers.

  8. Void detection beneath reinforced concrete sections: The practical application of ground-penetrating radar and ultrasonic techniques

    Science.gov (United States)

    Cassidy, Nigel J.; Eddies, Rod; Dods, Sam

    2011-08-01

    Ground-penetrating radar (GPR) and ultrasonic 'pulse echo' techniques are well-established methods for the imaging, investigation and analysis of steel reinforced concrete structures and are important civil engineering survey tools. GPR is, arguably, the more widely-used technique as it is suitable for a greater range of problem scenarios (i.e., from rebar mapping to moisture content determination). Ultrasonic techniques are traditionally associated with the engineering-based, non-destructive testing of concrete structures and their integrity analyses (e.g., flaw detection, shear/longitudinal velocity determination, etc). However, when used in an appropriate manner, both techniques can be considered complementary and provide a unique way of imaging the sub-surface that is suited to a range of geotechnical problems. In this paper, we present a comparative study between mid-to-high frequency GPR (450 MHz and 900 MHz) and array-based, shear wave, pulse-echo ultrasonic surveys using proprietary instruments and conventional GPR data processing and visualisation techniques. Our focus is the practical detection of sub-metre scale voids located under steel reinforced concrete sections in realistic survey conditions (e.g., a capped, relict mine shaft or vent). Representative two-dimensional (2D) sections are presented for both methods illustrating the similarities/differences in signal response and the temporal-spatial target resolutions achieved with each technique. The use of three-dimensional data volumes and time slices (or 'C-scans') for advanced interpretation is also demonstrated, which although common in GPR applications is under-utilised as a technique in general ultrasonic surveys. The results show that ultrasonic methods can perform as well as GPR for this specific investigation scenario and that they have the potential of overcoming some of the inherent limitations of GPR investigations (i.e., the need for careful antenna frequency selection and survey design in

  9. Ultrasonic testing device

    International Nuclear Information System (INIS)

    The ultrasonic transmitter made of polarized ferroelectric ceramic material (lead zirconate titanate) is arranged in a strip carrier which allows it to be introduced between the fuel elements of a fuel subassembly in a water cooled nuclear reactor. The ultrasonic transmitter is insulated relative to the carrier. The echo of the ra dal ultrasonic pulse is recorded which changes as faulty water filled fuel elements are detected. (RW)

  10. Ultrasonic techniques for process monitoring and control.

    Energy Technology Data Exchange (ETDEWEB)

    Chien, H.-T.

    1999-03-24

    Ultrasonic techniques have been applied successfully to process monitoring and control for many industries, such as energy, medical, textile, oil, and material. It helps those industries in quality control, energy efficiency improving, waste reducing, and cost saving. This paper presents four ultrasonic systems, ultrasonic viscometer, on-loom, real-time ultrasonic imaging system, ultrasonic leak detection system, and ultrasonic solid concentration monitoring system, developed at Argonne National Laboratory in the past five years for various applications.

  11. Determination Strength of Concrete in-Situ by Seismic Ultrasonic Method in Detecting Risky Structure

    Science.gov (United States)

    Uyanik, O.; Öziçer, S.; Sabbağ, N.

    2014-12-01

    Strength of concrete is important in the analysis of structures. Strength of concrete can be determined as destructive or non destructive. In order to determine to strength of concrete as destructive, core is taken from concrete parts of the structure and uniaxial compressive strength test is applied in the laboratory. In contrast, strength of concrete can be determined as non destructive in situ by seismic ultrasonic technique. In this study, seismic ultrasonic P wave velocity measurements. Schmidt hammer test in situ and core sampling along with uniaxial compressive test are carried out in order to determine the strength of concrete in existing structures in Bornova district of İzmir. Seismic ultrasonic P wave velocity measurements in situ were also applied on the core. The concrete strength values obtained from techniques applied in study were compared and error values are determined. By seismic ultrasonic P wave velocity measurements with error value %5 strength of concrete is determined quickly without any destruction on structures studied.

  12. Image processing applied to automatic detection of defects during ultrasonic examination

    International Nuclear Information System (INIS)

    This work is a study about image processing applied to ultrasonic BSCAN images which are obtained in the field of non destructive testing of weld. The goal is to define what image processing techniques can bring to ameliorate the exploitation of the data collected and, more precisely, what image processing can do to extract the meaningful echoes which enable to characterize and to size the defects. The report presents non destructive testing by ultrasounds in the nuclear field and it indicates specificities of the propagation of ultrasonic waves in austenitic weld. It gives a state of the art of the data processing applied to ultrasonic images in nondestructive evaluation. A new image analysis is then developed. It is based on a powerful tool, the co-occurrence matrix. This matrix enables to represent, in a whole representation, relations between amplitudes of couples of pixels. From the matrix analysis, a new complete and automatic method has been set down in order to define a threshold which separates echoes from noise. An automatic interpretation of the ultrasonic echoes is then possible. Complete validation has been done with standard pieces

  13. Method for evaluating bow tie filter angle-dependent attenuation in CT: Theory and simulation results

    International Nuclear Information System (INIS)

    Purpose: Dosimetry in computed tomography (CT) is increasingly based on Monte Carlo studies that define the dose in the patient (in mGy) as a function of air kerma (free in air) at isocenter (mGy). The accuracy of Monte Carlo studies depends in part on the accuracy of the characterization of the bow tie filter for a given CT scanner model. A simple method for characterizing the bow tie filter attenuation profile in CT scanners would therefore be very useful. The theory behind such a method is proposed. Methods: A measurement protocol is discussed mathematically and demonstrated using computer simulation. The proposed method requires the placement of a radiation monitor at the periphery of the CT field, and the time domain signal (kerma rate versus time) is measured with good temporal resolution (∼200 Hz or better) and with all other objects (e.g., patient couch) retracted from the field of view. Knowledge of the source to isocenter distance (or alternately, the isocenter to probe distance) is required. The stationary detector records the kerma rate versus time signal as the gantry rotates through several revolutions. From this temporal data, signal processing techniques are used to extract in-phase peaks, as well as out-of-phase kerma rate levels. From these data, the distance from isocenter to the probe can be determined (or, alternatively, the source to isocenter distance), and the angle-dependent bow tie filter attenuation can be computed. By measuring the angle-dependent bow tie filter attenuation at several kVp settings, the bow tie composition versus fan angle can be computed using basis decomposition techniques. Results: The simulations illustrated that with 2% added noise in the kerma rate versus time signal, the attenuation properties of a hypothetical two component (aluminum and polymethyl methacrylate) bow tie filter could be determined (r2>0.99). Although the computed basis material thicknesses were not exactly equal to the actual thicknesses, their

  14. An Ultrasonic Sensor System Based on a Two-Dimensional State Method for Highway Vehicle Violation Detection Applications

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2015-04-01

    Full Text Available With the continuing growth of highway construction and vehicle use expansion all over the world, highway vehicle traffic rule violation (TRV detection has become more and more important so as to avoid traffic accidents and injuries in intelligent transportation systems (ITS and vehicular ad hoc networks (VANETs. Since very few works have contributed to solve the TRV detection problem by moving vehicle measurements and surveillance devices, this paper develops a novel parallel ultrasonic sensor system that can be used to identify the TRV behavior of a host vehicle in real-time. Then a two-dimensional state method is proposed, utilizing the spacial state and time sequential states from the data of two parallel ultrasonic sensors to detect and count the highway vehicle violations. Finally, the theoretical TRV identification probability is analyzed, and actual experiments are conducted on different highway segments with various driving speeds, which indicates that the identification accuracy of the proposed method can reach about 90.97%.

  15. An Ultrasonic Sensor System Based on a Two-Dimensional State Method for Highway Vehicle Violation Detection Applications

    Science.gov (United States)

    Liu, Jun; Han, Jiuqiang; Lv, Hongqiang; Li, Bing

    2015-01-01

    With the continuing growth of highway construction and vehicle use expansion all over the world, highway vehicle traffic rule violation (TRV) detection has become more and more important so as to avoid traffic accidents and injuries in intelligent transportation systems (ITS) and vehicular ad hoc networks (VANETs). Since very few works have contributed to solve the TRV detection problem by moving vehicle measurements and surveillance devices, this paper develops a novel parallel ultrasonic sensor system that can be used to identify the TRV behavior of a host vehicle in real-time. Then a two-dimensional state method is proposed, utilizing the spacial state and time sequential states from the data of two parallel ultrasonic sensors to detect and count the highway vehicle violations. Finally, the theoretical TRV identification probability is analyzed, and actual experiments are conducted on different highway segments with various driving speeds, which indicates that the identification accuracy of the proposed method can reach about 90.97%. PMID:25894940

  16. Analytical Model for Estimating the Zenith Angle Dependence of Terrestrial Cosmic Ray Fluxes

    Science.gov (United States)

    Sato, Tatsuhiko

    2016-01-01

    A new model called “PHITS-based Analytical Radiation Model in the Atmosphere (PARMA) version 4.0” was developed to facilitate instantaneous estimation of not only omnidirectional but also angular differential energy spectra of cosmic ray fluxes anywhere in Earth’s atmosphere at nearly any given time. It consists of its previous version, PARMA3.0, for calculating the omnidirectional fluxes and several mathematical functions proposed in this study for expressing their zenith-angle dependences. The numerical values of the parameters used in these functions were fitted to reproduce the results of the extensive air shower simulation performed by Particle and Heavy Ion Transport code System (PHITS). The angular distributions of ground-level muons at large zenith angles were specially determined by introducing an optional function developed on the basis of experimental data. The accuracy of PARMA4.0 was closely verified using multiple sets of experimental data obtained under various global conditions. This extension enlarges the model’s applicability to more areas of research, including design of cosmic-ray detectors, muon radiography, soil moisture monitoring, and cosmic-ray shielding calculation. PARMA4.0 is available freely and is easy to use, as implemented in the open-access EXcel-based Program for Calculating Atmospheric Cosmic-ray Spectrum (EXPACS). PMID:27490175

  17. T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

    International Nuclear Information System (INIS)

    To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)

  18. Thickness determination of molecularly thin lubricant films by angle-dependent X-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    An angle-dependent X-ray photoelectron spectroscopy (XPS) method used to measure the thickness of molecularly thin lubricants was developed. The method was built based on an island model of patched overlayer on a flat substrate by using the photoemission signal solely from the lubricant film. Typical molecularly thin Zdol films on the CHx overcoat of unused commercial magnetic disks were measured to verify the metrology. The lubricant thickness determined by the metrology was equal to the recent result by thermostatic high vacuum atomic force microscopy. The measured deduction in the thickness of the molecularly thin lubricant films, successively irradiated by the monochromatic source operated at 14 kV/250 W, was as low as 1 A during the first irradiation hour. XPS spectra showed that no hydrocarbons, water or oxygen were adsorbed over the Zdol outer surfaces in the tested XPS conditions. The inelastic mean free path (IMFP) of C 1s in Zdol or in CHx was found to be independent of take off angle (TOA) when TOA o. The IMFP of C 1s in Zdol was ∼63.5 A and the lubricant island thickness was ∼35 A

  19. Analytical Model for Estimating the Zenith Angle Dependence of Terrestrial Cosmic Ray Fluxes.

    Science.gov (United States)

    Sato, Tatsuhiko

    2016-01-01

    A new model called "PHITS-based Analytical Radiation Model in the Atmosphere (PARMA) version 4.0" was developed to facilitate instantaneous estimation of not only omnidirectional but also angular differential energy spectra of cosmic ray fluxes anywhere in Earth's atmosphere at nearly any given time. It consists of its previous version, PARMA3.0, for calculating the omnidirectional fluxes and several mathematical functions proposed in this study for expressing their zenith-angle dependences. The numerical values of the parameters used in these functions were fitted to reproduce the results of the extensive air shower simulation performed by Particle and Heavy Ion Transport code System (PHITS). The angular distributions of ground-level muons at large zenith angles were specially determined by introducing an optional function developed on the basis of experimental data. The accuracy of PARMA4.0 was closely verified using multiple sets of experimental data obtained under various global conditions. This extension enlarges the model's applicability to more areas of research, including design of cosmic-ray detectors, muon radiography, soil moisture monitoring, and cosmic-ray shielding calculation. PARMA4.0 is available freely and is easy to use, as implemented in the open-access EXcel-based Program for Calculating Atmospheric Cosmic-ray Spectrum (EXPACS). PMID:27490175

  20. T1rho mapping of entire femoral cartilage using depth- and angle-dependent analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nozaki, Taiki; Kaneko, Yasuhito; Yu, Hon J.; Yoshioka, Hiroshi [University of California Irvine, Department of Radiological Sciences, Orange, CA (United States); Kaneshiro, Kayleigh [University of California Irvine, School of Medicine, Irvine, CA (United States); Schwarzkopf, Ran [University of California Irvine, Department of Orthopedic Surgery, Irvine, CA (United States); Hara, Takeshi [Gifu University Graduate School of Medicine, Department of Intelligent Image Information, Division of Regeneration and Advanced Medical Sciences, Gifu (Japan)

    2016-06-15

    To create and evaluate normalized T1rho profiles of the entire femoral cartilage in healthy subjects with three-dimensional (3D) angle- and depth-dependent analysis. T1rho images of the knee from 20 healthy volunteers were acquired on a 3.0-T unit. Cartilage segmentation of the entire femur was performed slice-by-slice by a board-certified radiologist. The T1rho depth/angle-dependent profile was investigated by partitioning cartilage into superficial and deep layers, and angular segmentation in increments of 4 over the length of segmented cartilage. Average T1rho values were calculated with normalized T1rho profiles. Surface maps and 3D graphs were created. T1rho profiles have regional and depth variations, with no significant magic angle effect. Average T1rho values in the superficial layer of the femoral cartilage were higher than those in the deep layer in most locations (p < 0.05). T1rho values in the deep layer of the weight-bearing portions of the medial and lateral condyles were lower than those of the corresponding non-weight-bearing portions (p < 0.05). Surface maps and 3D graphs demonstrated that cartilage T1rho values were not homogeneous over the entire femur. Normalized T1rho profiles from the entire femoral cartilage will be useful for diagnosing local or early T1rho abnormalities and osteoarthritis in clinical applications. (orig.)

  1. Applying a nonlinear, pitch-catch, ultrasonic technique for the detection of kissing bonds in friction stir welds.

    Science.gov (United States)

    Delrue, Steven; Tabatabaeipour, Morteza; Hettler, Jan; Van Den Abeele, Koen

    2016-05-01

    Friction stir welding (FSW) is a promising technology for the joining of aluminum alloys and other metallic admixtures that are hard to weld by conventional fusion welding. Although FSW generally provides better fatigue properties than traditional fusion welding methods, fatigue properties are still significantly lower than for the base material. Apart from voids, kissing bonds for instance, in the form of closed cracks propagating along the interface of the stirred and heat affected zone, are inherent features of the weld and can be considered as one of the main causes of a reduced fatigue life of FSW in comparison to the base material. The main problem with kissing bond defects in FSW, is that they currently are very difficult to detect using existing NDT methods. Besides, in most cases, the defects are not directly accessible from the exposed surface. Therefore, new techniques capable of detecting small kissing bond flaws need to be introduced. In the present paper, a novel and practical approach is introduced based on a nonlinear, single-sided, ultrasonic technique. The proposed inspection technique uses two single element transducers, with the first transducer transmitting an ultrasonic signal that focuses the ultrasonic waves at the bottom side of the sample where cracks are most likely to occur. The large amount of energy at the focus activates the kissing bond, resulting in the generation of nonlinear features in the wave propagation. These nonlinear features are then captured by the second transducer operating in pitch-catch mode, and are analyzed, using pulse inversion, to reveal the presence of a defect. The performance of the proposed nonlinear, pitch-catch technique, is first illustrated using a numerical study of an aluminum sample containing simple, vertically oriented, incipient cracks. Later, the proposed technique is also applied experimentally on a real-life friction stir welded butt joint containing a kissing bond flaw. PMID:26921559

  2. A phase deviation based split-spectrum processing algorithm for ultrasonic flaw detection

    Institute of Scientific and Technical Information of China (English)

    LIU Zhenqing

    2002-01-01

    The Split Spectrum Processing (SSP) technique has proved its ability in reduction of interference noise in ultrasonic nondestructive testing for coarse grained materials. However,the results of SSP algorithms are not sufficiently stable since they are sensitive to the filter bank and filter parameters. And the mechanism of the technique to fully explore the signals is not clear. The statistical phase response characteristic of filter outputs for ultrasonic testing is discussed. Thus, a new SSP algorithm based on phase standard deviation is proposed. The performance is examined for both computer simulated and experimental data, and compared to commonly used minimum algorithm. The phase standard deviation algorithm is proved its superior effect and is less sensitive on the number of filters.

  3. An optimal baseline selection methodology for data-driven damage detection and temperature compensation in acousto-ultrasonics

    Science.gov (United States)

    Torres-Arredondo, M.-A.; Sierra-Pérez, Julián; Cabanes, Guénaël

    2016-05-01

    The process of measuring and analysing the data from a distributed sensor network all over a structural system in order to quantify its condition is known as structural health monitoring (SHM). For the design of a trustworthy health monitoring system, a vast amount of information regarding the inherent physical characteristics of the sources and their propagation and interaction across the structure is crucial. Moreover, any SHM system which is expected to transition to field operation must take into account the influence of environmental and operational changes which cause modifications in the stiffness and damping of the structure and consequently modify its dynamic behaviour. On that account, special attention is paid in this paper to the development of an efficient SHM methodology where robust signal processing and pattern recognition techniques are integrated for the correct interpretation of complex ultrasonic waves within the context of damage detection and identification. The methodology is based on an acousto-ultrasonics technique where the discrete wavelet transform is evaluated for feature extraction and selection, linear principal component analysis for data-driven modelling and self-organising maps for a two-level clustering under the principle of local density. At the end, the methodology is experimentally demonstrated and results show that all the damages were detectable and identifiable.

  4. Detection of alkali-silica reaction by means of ultrasonic sounding - a pilot study

    Czech Academy of Sciences Publication Activity Database

    Lokajíček, Tomáš; Petružálek, Matěj; Svitek, Tomáš; Šťastná, A.; Šachlová, Š.

    Montréal: Canadian Institute of Mining , Metallurgy and Petroleum, 2015. ISBN 978-1-926872-25-4. [International Congress of Rock Mechanics /13./. Montréal (CA), 10.05.2015-13.05.2015] R&D Projects: GA ČR(CZ) GAP104/12/0915 Institutional support: RVO:67985831 Keywords : Mortar bar test * ASR * aggregates * ultrasonic sounding * time domain analysis * longitudinal wave velocity * frequency domain analysis Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  5. A Pattern Recognition Approach for Damage Detection and Temperature Compensation in Acousto-Ultrasonics

    OpenAIRE

    Torres Arredondo, Miguel Angel; Sierra-Pérez, Julián; Zenuni, Erion; Cabanes, Guénaël; Rodellar, José; Güemes, Alfredo; Fritzen, Claus-Peter

    2014-01-01

    International audience The global trends in the construction of modern structures require the integration of sensors together with data recording and analysis modules so that their integrity can be continuously monitored for safe-life, economic and ecological reasons. This process of measuring and analysing the data from a distributed sensor network all over a structural system in order to quantify its condition is known as structural health monitoring (SHM). Guided ultrasonic wave-based t...

  6. Ultrasonic detection variability of weld defects and the effect on fracture mechanics predictions - an experimental assessment

    International Nuclear Information System (INIS)

    Discrete, artificial weld defects, simulating lack of fusion, were introduced into a series of thirty test plates of a medium strength structural steel. Two welding processes (MMA and SAW) were used. Each test weld was then ultrasonically examined by fourteen different operators to obtain predictions of defect geometry and position. Twenty of the test plates were then destructively tested under controlled four point bending to obtain measured failure loads, and the defect parameters length, height and depth were accurately measured from the resulting fracture surfaces. Very considerable variability in these defect parameters, both between operators and between predicted and actual defects, was observed. The ultrasonic data has been used quantitatively in conjunction with two widely used failure assessment procedures, viz. the COD approach of British Standard's PD 6493 (1980), and the U.K. Central Electricity Generating Board's Two-criteria or R-6 Method (1980), to study the effect of ultrasonic defect sizing on fracture mechanics predictions. Results indicate compatibility between the two approaches and a considerable tolerance to variations in defect sizes in failure prediction estimation

  7. An angle-dependent estimation of CT x-ray spectrum from rotational transmission measurements

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yuan, E-mail: yuan.lin@duke.edu; Samei, Ehsan [Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 and Physics Department, Duke University, Durham, North Carolina 27708 (United States); Ramirez-Giraldo, Juan Carlos [Siemens Medical Solutions, Malvern, Pennsylvania 19355 (United States); Gauthier, Daniel J. [Physics Department, Duke University, Durham, North Carolina 27708 (United States); Stierstorfer, Karl [Siemens Healthcare, Forchheim 91301 (Germany)

    2014-06-15

    Purpose: Computed tomography (CT) performance as well as dose and image quality is directly affected by the x-ray spectrum. However, the current assessment approaches of the CT x-ray spectrum require costly measurement equipment and complicated operational procedures, and are often limited to the spectrum corresponding to the center of rotation. In order to address these limitations, the authors propose an angle-dependent estimation technique, where the incident spectra across a wide range of angular trajectories can be estimated accurately with only a single phantom and a single axial scan in the absence of the knowledge of the bowtie filter. Methods: The proposed technique uses a uniform cylindrical phantom, made of ultra-high-molecular-weight polyethylene and positioned in an off-centered geometry. The projection data acquired with an axial scan have a twofold purpose. First, they serve as a reflection of the transmission measurements across different angular trajectories. Second, they are used to reconstruct the cross sectional image of the phantom, which is then utilized to compute the intersection length of each transmission measurement. With each CT detector element recording a range of transmission measurements for a single angular trajectory, the spectrum is estimated for that trajectory. A data conditioning procedure is used to combine information from hundreds of collected transmission measurements to accelerate the estimation speed, to reduce noise, and to improve estimation stability. The proposed spectral estimation technique was validated experimentally using a clinical scanner (Somatom Definition Flash, Siemens Healthcare, Germany) with spectra provided by the manufacturer serving as the comparison standard. Results obtained with the proposed technique were compared against those obtained from a second conventional transmission measurement technique with two materials (i.e., Cu and Al). After validation, the proposed technique was applied to measure

  8. An angle-dependent estimation of CT x-ray spectrum from rotational transmission measurements

    International Nuclear Information System (INIS)

    Purpose: Computed tomography (CT) performance as well as dose and image quality is directly affected by the x-ray spectrum. However, the current assessment approaches of the CT x-ray spectrum require costly measurement equipment and complicated operational procedures, and are often limited to the spectrum corresponding to the center of rotation. In order to address these limitations, the authors propose an angle-dependent estimation technique, where the incident spectra across a wide range of angular trajectories can be estimated accurately with only a single phantom and a single axial scan in the absence of the knowledge of the bowtie filter. Methods: The proposed technique uses a uniform cylindrical phantom, made of ultra-high-molecular-weight polyethylene and positioned in an off-centered geometry. The projection data acquired with an axial scan have a twofold purpose. First, they serve as a reflection of the transmission measurements across different angular trajectories. Second, they are used to reconstruct the cross sectional image of the phantom, which is then utilized to compute the intersection length of each transmission measurement. With each CT detector element recording a range of transmission measurements for a single angular trajectory, the spectrum is estimated for that trajectory. A data conditioning procedure is used to combine information from hundreds of collected transmission measurements to accelerate the estimation speed, to reduce noise, and to improve estimation stability. The proposed spectral estimation technique was validated experimentally using a clinical scanner (Somatom Definition Flash, Siemens Healthcare, Germany) with spectra provided by the manufacturer serving as the comparison standard. Results obtained with the proposed technique were compared against those obtained from a second conventional transmission measurement technique with two materials (i.e., Cu and Al). After validation, the proposed technique was applied to measure

  9. 产前超声检测胎儿胸腺%Prenatal ultrasonic detecting and evaluating for fetal thymus

    Institute of Scientific and Technical Information of China (English)

    凌乐文

    2012-01-01

    Detecting and evaluating for fetal thymus with prenatal ultrasound is very important for diagnosis of dysplastic thymus and relative malformations or diseases. The development and application of new technology helps to the assessment of development of the fetal thymus. Ultrasonic technologies of detecting and evaluating for fetal thymus were reviewed in the article.%产前超声检测胎儿胸腺对诊断胎儿胸腺发育异常及相关畸形或疾病有重要作用,新技术的发展和应用可更全面地评估胎儿胸腺的发育.本文对胎儿胸腺超声检测技术及临床应用进行综述.

  10. A STRUCTURAL IMPACT ASSESSMENT OF FLAWS DETECTED DURING ULTRASONIC EXAMINATION OF TANK 15

    Energy Technology Data Exchange (ETDEWEB)

    Wiersma, B; James Elder, J

    2008-08-21

    Ultrasonic (UT) inspection of Tank 15 was conducted between April and July 2007 in accordance with the Tank 15 UT inspection plan. This was a planned re-inspection of this tank, the previous one was performed in 2002. Ten cracks were characterized in the previous examination. The re-inspection was performed to verify the present models and understanding for stress corrosion cracking. During this re-examination, one indication that was initially reported as a 'possible perpendicular crack <25% through wall' in 2002, was clearly shown not to be a crack. Additionally, examination of a new area immediately adjacent to other cracks along a vertical weld revealed three new cracks. It is not known when these new cracks formed as they could very well have been present in 2002 as well. Therefore, a total of twelve cracks were evaluated during the re-examination. A critical review of the information describing stress corrosion crack behavior for the SRS waste tanks, as well as a summary review of the service history of Tank 15, was performed. Each crack was then evaluated for service exposure history, consistency of the crack behavior with the current understanding of stress corrosion cracking, and present and future impact to the structural integrity of the tank. Crack instability calculations were performed on each crack for a bounding waste removal loading condition in Tank 15. In all cases, the crack behavior was determined to be consistent with the previous understanding of stress corrosion cracking in the SRS waste tank environment. The length of the cracks was limited due to the short-range nature of the residual stresses near seam, repair and attachment welds. Of the twelve cracks, nine were located in the vapor space above the sludge layer, including the three new cracks. Comparison of the crack lengths measured in 2002 and 2007 revealed that crack growth had occurred in four of the six previously measured vapor space cracks. However, the growth remained

  11. Assessment of Crack Detection in Heavy-Walled Cast Stainless Steel Piping Welds Using Advanced Low-Frequency Ultrasonic Methods

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Michael T.; Crawford, Susan L.; Cumblidge, Stephen E.; Denslow, Kayte M.; Diaz, Aaron A.; Doctor, Steven R.

    2007-03-01

    Studies conducted at the Pacific Northwest National Laboratory in Richland, Washington, have focused on assessing the effectiveness and reliability of novel approaches to nondestructive examination (NDE) for inspecting coarse-grained, cast stainless steel reactor components. The primary objective of this work is to provide information to the U.S. Nuclear Regulatory Commission on the effectiveness and reliability of advanced NDE methods as related to the inservice inspection of safety-related components in pressurized water reactors (PWRs). This report provides progress, recent developments, and results from an assessment of low frequency ultrasonic testing (UT) for detection of inside surface-breaking cracks in cast stainless steel reactor piping weldments as applied from the outside surface of the components. Vintage centrifugally cast stainless steel piping segments were examined to assess the capability of low-frequency UT to adequately penetrate challenging microstructures and determine acoustic propagation limitations or conditions that may interfere with reliable flaw detection. In addition, welded specimens containing mechanical and thermal fatigue cracks were examined. The specimens were fabricated using vintage centrifugally cast and statically cast stainless steel materials, which are typical of configurations installed in PWR primary coolant circuits. Ultrasonic studies on the vintage centrifugally cast stainless steel piping segments were conducted with a 400-kHz synthetic aperture focusing technique and phased array technology applied at 500 kHz, 750 kHz, and 1.0 MHz. Flaw detection and characterization on the welded specimens was performed with the phased array method operating at the frequencies stated above. This report documents the methodologies used and provides results from laboratory studies to assess baseline material noise, crack detection, and length-sizing capability for low-frequency UT in cast stainless steel piping.

  12. Assessment of Crack Detection in Heavy-Walled Cast Stainless Steel Piping Welds Using Advanced Low-Frequency Ultrasonic Methods

    International Nuclear Information System (INIS)

    Studies conducted at the Pacific Northwest National Laboratory in Richland, Washington, have focused on assessing the effectiveness and reliability of novel approaches to nondestructive examination (NDE) for inspecting coarse-grained, cast stainless steel reactor components. The primary objective of this work is to provide information to the U.S. Nuclear Regulatory Commission on the effectiveness and reliability of advanced NDE methods as related to the inservice inspection of safety-related components in pressurized water reactors (PWRs). This report provides progress, recent developments, and results from an assessment of low frequency ultrasonic testing (UT) for detection of inside surface-breaking cracks in cast stainless steel reactor piping weldments as applied from the outside surface of the components. Vintage centrifugally cast stainless steel piping segments were examined to assess the capability of low-frequency UT to adequately penetrate challenging microstructures and determine acoustic propagation limitations or conditions that may interfere with reliable flaw detection. In addition, welded specimens containing mechanical and thermal fatigue cracks were examined. The specimens were fabricated using vintage centrifugally cast and statically cast stainless steel materials, which are typical of configurations installed in PWR primary coolant circuits. Ultrasonic studies on the vintage centrifugally cast stainless steel piping segments were conducted with a 400-kHz synthetic aperture focusing technique and phased array technology applied at 500 kHz, 750 kHz, and 1.0 MHz. Flaw detection and characterization on the welded specimens was performed with the phased array method operating at the frequencies stated above. This report documents the methodologies used and provides results from laboratory studies to assess baseline material noise, crack detection, and length-sizing capability for low-frequency UT in cast stainless steel piping

  13. Angle dependence of the frequency correlation in random photonic media: Diffusive regime and its breakdown near localization

    NARCIS (Netherlands)

    Muskens, O.L.; Beek, van der T.; Lagendijk, A.

    2011-01-01

    The frequency correlations of light in complex photonic media are of interest as a tool for characterizing the dynamical aspects of light diffusion. We demonstrate here that the frequency correlation shows a pronounced angle dependence both in transmission and in reflection geometries. Using a broad

  14. 火力发电厂厚壁管超声波检测方案%A thick walled tube ultrasonic detection scheme in thermal power plant

    Institute of Scientific and Technical Information of China (English)

    胡戊希

    2011-01-01

    目前火力发电厂机组容量大,管道多采用厚壁管,对厚壁管的对接焊缝进行超声波检测时,为了提高侧壁未熔合缺陷的检测率,提出采用适当的超声波探头,特别是正确的探头角度,制订出超声波的检测方案。%Now units are with high capacity in the thermal power plant, and pipeline uses thick walled tube. For thick wal/ed tube on ultrasonic testing, in order to improve fault detection rate of high lateral incomplete fusion defect,it puts forward adopting proper ultrasonic probe, especially correct probe angle, to formulate ultrasonic detection scheme.

  15. Development of ultrasonic techniques for the detection and measurement of intergranular attack in PWR steam generator tubes

    International Nuclear Information System (INIS)

    An ultrasonic technique has been developed for detecting and estimating the depth of intergranular attack (IGA) layers in PWR steam generator tubing. The debonding of the grains due to corrosion produces a reduction in ultrasonic velocity, making the transit time across the tube wall longer in corroded than in uncorroded material. A digital method of measuring the change in transit time to a precision of about 2 nsec has been developed and ways of compensating for typical dimensional imperfects in the tubes worked out. The application of the method within the transition zone at the end of the hydraulic expansion is being investigated. The method has been tested on about forty samples, produced from sensitized tubing, mainly in sulphur-bearing environments, comparing change in transit time with the attack depth found by sectioning. The samples as a whole show a wide range of behavior, although the majority fall into a sufficiently well defined group to form a basis for prediction of attack depth from change in transit time. A phenomenological model which describes some features of the data is presented and its relation to recent theoretical predictions and to structural information about the samples is discussed

  16. The effects of compressive stress and contamination liquids on the ultrasonic detection of fatigue cracks

    International Nuclear Information System (INIS)

    The influence of compressive stress on the reflection and transmission of ultrasound has been investigated for fatigue cracks. An examination has been made of the shear wave corner echoes from surface breaking fatigue cracks which were grown at constant stress intensity factor to control the roughness of the faces. In this way a correlation has been established between the roughness of the surfaces and the ultrasonic response at both zero load and under stress. The effect of liquids in the cracks has also been studied and the results compared with theoretical predictions for a thin sided parallel gap. (author)

  17. Applications of Flexible Ultrasonic Transducer Array for Defect Detection at 150 °C

    OpenAIRE

    Jiunn-Woei Liaw; Jing-Chi Tzeng; Chun-Hsiung Chiu; Jeanne-Louise Shih; Kuo-Ting Wu; Cheng-Kuei Jen

    2013-01-01

    In this study, the feasibility of using a one dimensional 16-element flexible ultrasonic transducer (FUT) array for nondestructive testing at 150 °C is demonstrated. The FUT arrays were made by a sol-gel sprayed piezoelectric film technology; a PZT composite film was sprayed on a titanium foil of 75 µm thickness. Since the FUT array is flexible, it was attached to a steel pipe with an outer diameter of 89 mm and a wall thickness of 6.5 mm at 150 °C. Using the ultras...

  18. Experience on crack detection of tube bundles in the tube sheet area by means of ultrasonics

    International Nuclear Information System (INIS)

    Nucon Inspection and Plant Services has applied the Nerason Ultrasonic Measurement System to more than eight different Nuclear Power Plants in the last three years. In this period some steam generators have been measured more than once to enable the trend to be analysed. The bore side measurements were carried out on straight tubes from 10 mm, and on curved tubes from 15 mm inner diameter. Minimum radius bend was 80 mm for 20 mm diameter tubes. The Nerason system is a versatile system which by changing the reflecting mirror can be simply adapted for the measurement of wall thickness, sleeve welds, profilometry, longitudinal and circumferential cracks. (author)

  19. Assessment of aircraft structural integrity by detecting disbonds through ultrasonic scanning

    Science.gov (United States)

    Abedin, M. N.; Prabhu, D. R.; Winfree, W. P.

    1992-01-01

    A study of nondestructive evaluation of aircraft bonded joints using the contact scanning technique is presented. Reflected signals acquired through the contacting transducer characterize the test region as being bonded or disbonded. Ultrasonic signals are attenuated more rapidly in the bonded regions when compared to disbonded regions. A peak amplitude based method and an artificial neural network are used to classify the signals. Results obtained using an artificial neural network exhibited significant insensitivity to signal variation when compared to the peak amplitude. Very good agreement is observed between results obtained using the present technique and those obtained using immersion scanning.

  20. An interferometer experiment to explore the aspect angle dependence of stimulated electromagnetic emission spectra

    Directory of Open Access Journals (Sweden)

    Isham

    2005-01-01

    view of the not yet understood but complex relationship between electrostatic fluctuations and SEE, it is of interest to investigate experimentally whether a similar angular structure is present in the various spectral features of the SEE signals and to compare the results with radar and other observations of RF-pump-induced effects. To this end we describe a simple two-element radio interferometer designed to search for aspect angle dependence of SEE features. We present an example of the initial data produced by this system, and draw preliminary conclusions based on the example data.

  1. Automated ultrasonic inspection for crack detection at F-111 lower wing skin fastener holes

    International Nuclear Information System (INIS)

    The failure of an F-l I I wing during a full-scale fatigue test had important implications for the structural integrity management of the RAAF F- I I I fleet. This failure was due to a fatigue crack which initiated in the bore of a fastener hole. To assure structural integrity, an automated ultrasonic inspection has been developed which will be applied to up to 1200 fastener holes in each wing. The holes are inspected from the lower surface and definitive assessments of wing serviceability must be made without removing fasteners. The inspection system uses focussed immersion probes to perform a 45-degree angle-beam shear wave inspection, utilising full-waveform capture and post-processing. This style of complex, computer-based inspection system is new to the Australian Defence Organisation and challenged many existing engineering processes for performing NDT and interpreting the results. This paper reviews the application of automated ultrasonic inspection for the F- l I I lower wing skin and outlines some of the significant challenges for both the science behind the inspection and the associated engineering processes. The lessons learnt will aid the successful integration of new technologies into existing NDT practices in the future

  2. Random forest learning of ultrasonic statistical physics and object spaces for lesion detection in 2D sonomammography

    Science.gov (United States)

    Sheet, Debdoot; Karamalis, Athanasios; Kraft, Silvan; Noël, Peter B.; Vag, Tibor; Sadhu, Anup; Katouzian, Amin; Navab, Nassir; Chatterjee, Jyotirmoy; Ray, Ajoy K.

    2013-03-01

    Breast cancer is the most common form of cancer in women. Early diagnosis can significantly improve lifeexpectancy and allow different treatment options. Clinicians favor 2D ultrasonography for breast tissue abnormality screening due to high sensitivity and specificity compared to competing technologies. However, inter- and intra-observer variability in visual assessment and reporting of lesions often handicaps its performance. Existing Computer Assisted Diagnosis (CAD) systems though being able to detect solid lesions are often restricted in performance. These restrictions are inability to (1) detect lesion of multiple sizes and shapes, and (2) differentiate between hypo-echoic lesions from their posterior acoustic shadowing. In this work we present a completely automatic system for detection and segmentation of breast lesions in 2D ultrasound images. We employ random forests for learning of tissue specific primal to discriminate breast lesions from surrounding normal tissues. This enables it to detect lesions of multiple shapes and sizes, as well as discriminate between hypo-echoic lesion from associated posterior acoustic shadowing. The primal comprises of (i) multiscale estimated ultrasonic statistical physics and (ii) scale-space characteristics. The random forest learns lesion vs. background primal from a database of 2D ultrasound images with labeled lesions. For segmentation, the posterior probabilities of lesion pixels estimated by the learnt random forest are hard thresholded to provide a random walks segmentation stage with starting seeds. Our method achieves detection with 99.19% accuracy and segmentation with mean contour-to-contour error lesions.

  3. 超声波多普勒流量检测系统电路设计%Design of Ultrasonic Doppler Flow Detection System Circuit

    Institute of Scientific and Technical Information of China (English)

    兰羽; 屈改平

    2013-01-01

    At present, most of the flow meter in the industry still use the zero-crossing detection method,it has larger error. Ultrasonic Doppler flowmeter possess high resolution, relatively high precision, free from external factors. On the basis of the analysis of ultrasonic Doppler flow detection system principle, the ultrasonic flow detection is designed. The ultrasonic tronsmittet circuit is designed by using 555 timer, the receiver circuit and the frequency signal detection circuit is designed by OPA27 chip. Experimental results show that the systematic errors are less than 3%, to meet the design requirements.%目前,在工业上大部分流量计仍采用过零检测法,误差较大.超声波多普勒流量计具有分辨率高、精度相对较高、不受外界因素影响等优点.在分析超声波多普勒流量计原理的基础上,设计了超声波流量检测系统,采用了555定时器设计了超声波发射电路、OPA27芯片设计了接收电路,及差频信号检测电路.经实验表明系统误差小于3%,满足设计要求.

  4. Development and Evaluation of Real-time Acoustic Detection System of Harmful Red-tide Using Ultrasonic Sound

    Directory of Open Access Journals (Sweden)

    Donhyug Kang

    2013-03-01

    Full Text Available The toxic, Harmful Algal Blooms (HABs caused by the Cochlodinium polykrikoides have a serious impact on the coastal waters of Korea. In this study, the acoustic detection system was developed for rapid HABs detection, based on the acoustic backscattering properties of the C. polykrikoides. The developed system was mainly composed of a pulser-receiver board, a signal processor board, a control board, a network board, a power board, ultrasonic sensors (3.5 and 5.0 MHz, an environmental sensor, GPS, and a land-based control unit. To evaluate the performance of the system, a trail was done at a laboratory, and two in situ trials were conducted: (1 when there was no red tide, and (2 when there was red tide. In the laboratory evaluation, the system performed well in accordance with the number of C. polykrikoides in the received level. Second, under the condition when there was no red tide in the field, there was a good correlation between the acoustic data and sampling data. Finally, under the condition when there was red tide in the field, the system successfully worked at various densities in accordance with the number of C. polykrikoides, and the results corresponded with the sampling data and monitoring result of NFRDI (National Fisheries Research & Development Institute. From the laboratory and field evaluations, the developed acoustic detection system for early detecting HABs has demonstrated that it could be a significant system to monitor the occurrence of HABs in coastal regions.

  5. Sensibility of hydrous ethanol adulteration detection using ultrasonic parameters validated in a metrological base

    International Nuclear Information System (INIS)

    The aim of this study is to identify possible changes in fuels, in this case hydrous ethanol, through ultrasonic parameters such as attenuation and propagation speed. The system setup and method were implemented at Inmetro's Laboratory of Ultrasound. Experiments and method uncertainties were assessed accordingly to ISO/IEC Guide 98 1:2009 (Uncertainty of measurement - Part 1: Introduction to the expression of uncertainty in measurement). Mixtures of ethanol and water varying from 90% to 94% of alcohol in mass were used as testing samples. Attenuation and propagation speed were accurately measured and uncertainties evaluated. The accordingly to Brazilian biofuel regulations, the concentration of water in hydrous ethanol can be accepted at a maximum concentration of 93.8 and minimum of 92.6 of alcohol in mass. To achieve that figure, a functional combination of tested parameters should be implemented. Those results could be used as a tool to identify adulteration of biofuel, even in analysis performed on site.

  6. Sensibility of hydrous ethanol adulteration detection using ultrasonic parameters validated in a metrological base

    Science.gov (United States)

    K-K Figueiredo, Monique; Costa-Felix, Rodrigo P. B.; Maggi, Luis E.; Alvarenga, André V.; Romeiro, Gilberto A.

    2011-02-01

    The aim of this study is to identify possible changes in fuels, in this case hydrous ethanol, through ultrasonic parameters such as attenuation and propagation speed. The system setup and method were implemented at Inmetro's Laboratory of Ultrasound. Experiments and method uncertainties were assessed accordingly to ISO/IEC Guide 98 1:2009 (Uncertainty of measurement - Part 1: Introduction to the expression of uncertainty in measurement). Mixtures of ethanol and water varying from 90% to 94% of alcohol in mass were used as testing samples. Attenuation and propagation speed were accurately measured and uncertainties evaluated. The accordingly to Brazilian biofuel regulations, the concentration of water in hydrous ethanol can be accepted at a maximum concentration of 93.8 and minimum of 92.6 of alcohol in mass. To achieve that figure, a functional combination of tested parameters should be implemented. Those results could be used as a tool to identify adulteration of biofuel, even in analysis performed on site.

  7. Development on ultrasonic testing technique for weldment of small diameter pipe branch. A case of trouble at a nuclear power station and development of ultrasonic testing technique (V-detection method)

    International Nuclear Information System (INIS)

    The weldment between a mother tube and a nozzle stub of small diameter pipings at a nuclear power station (austenitic stainless steel) has conventionally been inspected by the liquid penetrant testing (PT). However, on December, 1998, a leak trouble caused by inner flaw at welded portion formed, and then to confirm soundness of the weldment, necessity of not surface inspection (containing PT, and so on) but volume inspection was required. For the volume inspection, there were considered on radiographic testing (RT) and ultrasonic testing (UT). However, RT has a limitation such as detection of radiation in site and so on, so application of UT has been desired. To solve a problem with conventional method, a flaw detection arrangement to input ultrasonic wave directly to a flaw was considered. Because of V-letter arrangement of a detection feeler for transmission and receiving to a branch pipe, this method is called V-detection method. As a result of an experiment on nozzle stub weldment at an actual machine by using this method, it was found that all of flaws in the nozzle stub detected by RT could also be detected by using UT. (G.K.)

  8. Characterization of Angle Dependent Color Travel of Printed Multi-Color Effect Pigment on Different Color Substrates

    OpenAIRE

    Mirica Karlovits

    2014-01-01

    Color-travel pigments, which exhibit much more extensive color change as well provide angle-dependent optical effect can be used in many industrial products. In present paper the multi-color effect pigment printed on three different foils with different background color (black, silver and transparent) was investigated. The pigment was based on synthetically produced transparent silicon dioxide platelets coated with titanium dioxide. CIEL*a*b* values and reflection of prints were measured by m...

  9. Effects of finite electron mean free path on the attenuation, electromagnetic generation, and detection of ultrasonic shear waves in superconductors

    International Nuclear Information System (INIS)

    Use of the general many-body formalism allows us to derive a system of equations describing the propagation of electromagnetic shear waves coupled to ultrasonic shear waves in normal and superconducting metals with arbitrary electron mean free paths. From this system of equations we derive general expressions in terms of correlation functions for the attenuation coefficient as well as for the generation and detection (radiation) efficiency of ultrasonic shear waves, assuming specular reflection. It is shown that, for arbitrary mean free path, generation and radiation efficiency are equal. Furthermore, they are related in a simple way to the residual surface resistance caused by ultrasound generation. In order to incorporate the frictional force between electrons and lattice, a reactive part of which remains finite even at T=0, one has to introduce the current-stress tensor correlation function. The calculation of this correlation function for an impure BCS superconductor is more complicated than the calculation of the conductivity from the current-current correlation function. If suitable normalized, electromagnetic contribution to the attenuation coefficient depends on mean free path only through the conductivity. For sufficiently short mean free path the generation and radiation efficiency in a superconductor can become equal to and even larger than the efficiency in the normal metal because the frictional force, which opposes the electromagnetic field driving the ions, is less effective in the superconducting than in the normal state. It is shown that the interpretation of experiments on the radiation efficiency in superconducting tin has to be modified when the finite electron mean free path is taken into account. Agreement between theory and experiment can still be achieved by a suitable choice of the Fermi velocity and the mean free path. The London penetration depth calculated from this Fermi velocity turns out to be smaller than generally accepted values

  10. Study of a method for the defect detection by ultrasonic's technic: Prony's method, theory and practice

    International Nuclear Information System (INIS)

    The goal of PRONY's method is to identify a sampling of N signal's values with a finite linear development of p complex exponentials. This work has been done to use this method for the identification of a signal obtained by ''insonification'' (i.e. by interacting with an ultrasonic impulsion) of a target. The identified complex exponentials give the constitutive amplitudes, dampings, frequencies and phases of the signal, these values characterize geometry and size of unknown targets. Mathematics involve that the solution of 3D-elastodynamic equations is given asymptotically in time by an infinite summation of complex exponentials. The signal obtained by ''insonification'' is characteristic of this solution: it means that PRONY's method can be well suited for this identification. For that it was necessary to understand this method in all its aspects. Consequently in paragraph 1 we expose its principle and algorithm. We prove, it is one of its advantage, that PRONY's is an interpolation method if N = 2p. If N > 2p the method is working like a least square method. We study, at the paragraph 2, how the two essentials parameters N and p of the method interact one with the other. The influence of the noise is observed, knowing that a complete study of it will need some developments out of this presentation. And then we approach, in the paragraph 3, the practice of the method, in order to verify its quality for identified tests problems. Successively we analyze a damping signal, an electric signal with damping, a pure periodic signal. The behaviour of PRONY's is excellent with a few precautions that we specify. Finally we are interested with a ''realistic'' seismic signal. The ultrasonic wave iteration with defect is then observed in paragraph 4. Physical and experimental device are briefly described. The identification's problem of a target, in practice the identification of a defect, is still widely opened if we use PRONY. Is it necessary to give up. Certainly not, the

  11. Sensibility of hydrous ethanol adulteration detection using ultrasonic parameters validated in a metrological base

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, Monique K-K; Costa-Felix, Rodrigo P B; Maggi, Luis E; Alvarenga, Andre V [Laboratory of Ultrasound (LABUS), Directory of Scientific and Industrial Metrology (DIMCI), National Institute of Metrology, Standardization, and Industrial Quality - Inmetro, Av. Nossa Sra das Gracas, 50 Predio 1, Duque de Caxias, RJ, ZIP 25250-020 (Brazil); Romeiro, Gilberto A, E-mail: mkfigueiredo@inmetro.gov.br, E-mail: rpfelix@inmetro.gov.br, E-mail: lemaggi@inmetro.gov.br, E-mail: avalvarenga@inmetro.gov.br, E-mail: gilbertoromeiro@ig.com.br [Depto of Organic Chemistry, Institute of Chemistry, Fluminense Federal University (UFF), Campus of Valonguinho, Outeiro de Sao Joao Batista, s/n, Niteroi, RJ, ZIP 24020150 (Brazil)

    2011-02-01

    The aim of this study is to identify possible changes in fuels, in this case hydrous ethanol, through ultrasonic parameters such as attenuation and propagation speed. The system setup and method were implemented at Inmetro's Laboratory of Ultrasound. Experiments and method uncertainties were assessed accordingly to ISO/IEC Guide 98 1:2009 (Uncertainty of measurement - Part 1: Introduction to the expression of uncertainty in measurement). Mixtures of ethanol and water varying from 90% to 94% of alcohol in mass were used as testing samples. Attenuation and propagation speed were accurately measured and uncertainties evaluated. The accordingly to Brazilian biofuel regulations, the concentration of water in hydrous ethanol can be accepted at a maximum concentration of 93.8 and minimum of 92.6 of alcohol in mass. To achieve that figure, a functional combination of tested parameters should be implemented. Those results could be used as a tool to identify adulteration of biofuel, even in analysis performed on site.

  12. Flash Flood Detection in Urban Cities Using Ultrasonic and Infrared Sensors

    KAUST Repository

    Moussa, Moustafa

    2016-07-19

    Floods are the most common type of natural disaster. Often leading to loss of lives and properties in the thousands yearly. Among these events, urban flash floods are particularly deadly because of the short timescales on which they occur, and because of the population density of cities. Since most flood casualties are caused by a lack of information on the impending flood (type, location, severity), sensing these events is critical to generate accurate and detailed warnings and short term forecasts. However, no dedicated flash flood sensing systems, that could monitor the propagation of flash floods, in real time, currently exist in cities. In the present paper, firstly a new sensing device that can simultaneously monitor urban flash floods and traffic congestion has been presented. This sensing device is based on the combination of ultrasonic range-finding with remote temperature sensing, and can sense both phenomena with a high degree of accuracy, using a combination of L1-regularized reconstruction and artificial neural networks to process measurement data. Secondly, corresponding algorithms have been implemented on a low-power wireless sensor platform, and their performance in water level estimation in a 6 months test involving four different sensors is illustrated. The results demonstrate that urban water levels can be reliably estimated with error less than 2 cm, and that the preprocessing and machine learning schemes can run in real-time on currently available wireless sensor platforms.

  13. Ultrasonic Detection for the Crack of Desuperheater Nozzle%减温器管孔裂纹的超声检测

    Institute of Scientific and Technical Information of China (English)

    赵建忠; 苏波; 张永军

    2014-01-01

    分析了电站锅炉喷水减温器喷水管孔裂纹的超声检测方法,通过综合运用超声爬波与超声相控阵检测,能提高裂纹的检出率及定量精度,为缺陷监督运行或处理提供依据。%The ultrasonic detection method for the crack of water-jet nozzle of boiler desuperheater was analysed. By both adopting the detecting methods of ultrasonic creeping and phased array,the detecting rate and measurement accuracy can be increased,which provides basis for defects supervision and defects treatment.

  14. Prediction of the azimuth angle dependence of the quasimolecular anisotropy in heavy ion collisions

    International Nuclear Information System (INIS)

    Within the quasimolecular (MO) kinematic dipole model the authors predict a strong dependence of the anisotropy of the MO radiation on the orientation of the heavy ion scattering plane relative to the direction of the photon detection plane. (Auth.)

  15. Multivariate data-driven modelling and pattern recognition for damage detection and identification for acoustic emission and acousto-ultrasonics

    DEFF Research Database (Denmark)

    Torres-Arredondo, M.A.; Tibaduiza, D.-A.; McGugan, Malcolm; Toftegaard, Helmuth Langmaack; Borum, Kaj Kvisgaard; Mujica, L.E.; Rodellar, J.; Fritzen, C.-P.

    2013-01-01

    structural health monitoring (SHM) systems based on ultrasonic guided waves with focus on the acoustic emission and acousto-ultrasonics techniques. The use of a guided wave based approach is driven by the fact that these waves are able to propagate over relatively long distances, and interact sensitively and...

  16. Ultrasonics - a new method of bubble detection and level measuring in the main coolant lines of PWR reactors

    International Nuclear Information System (INIS)

    According to many experts, level measurements in the pressurizer do not give reliable information on the coolant level for all accident conditions. In PWR reactors, ultrasonic measurement at right angles to the flow direction using a piezoelectric ultrasonic transducer acting intermittently as transmitter and receiver is the most appropriate method. (orig./GL)

  17. Improved ultrasonic detection of fatigue cracks in Ti-6A1-4V by thermo-optical modulation

    International Nuclear Information System (INIS)

    Pulsed infrared laser irradiation was used to positively identify small fatigue cracks on the surface of fatigue damaged Ti-6Al-4V specimens. The resulting transient thermoelastic deformation perceptibly changes the opening of partially closed surface cracks without affecting other scatterers, such as surface grooves, corrosion pits, coarse grains, etc., that might hide the fatigue crack from ultrasonic detection. We found that this method, which was previously shown to be very effective in 2024 aluminum alloy, must be modified in order to successfully adapt it to Ti-6Al-4V titanium alloy, where significant thermo-optical modulation was found even from straight corners or open notches. This spurious modulation is caused by direct thermal modulation of the sound velocity in the intact material rather than thermal stresses via crack closure. Different methods have been developed to distinguished direct thermal modulation from crack-closure modulation due to thermoelastic stresses. It was found that the modified thermo-optical modulation method can increase the detectability of hidden fatigue cracks in Ti-6Al-4V specimens by approximately one order of magnitude. - This effort was sponsored by the Defense Advanced Research Projects Agency (DARPA) Multidisciplinary University Research Initiative (MURI), under Air Force Office of Scientific Research grant number F49620-96-1-0442

  18. Ultrasonic testing

    Energy Technology Data Exchange (ETDEWEB)

    Song, Sung Jin [Sungkwunkwan Univ., Seoul (Korea, Republic of); Jeong, Hyun Jo [Wonkwang Univ., Iksan (Korea, Republic of)

    2004-02-15

    For the proper performance of ultrasonic testing of steel welded joints, and anisotropic material it is necessary to have sound understanding on the underlying physics. To provide such an understanding, it is beneficial to have simulation tools for ultrasonic testing. In order to address such a need, we develop effective approaches to simulate angle beam ultrasonic testing with a personal computer. The simulation is performed using ultrasonic measurement models based on the computationally efficient multi-Gaussian beams. This reach will describe the developed ultrasonic testing models together with the experimental verification of their accuracy.

  19. Ultrasonic examination for detection of planar defects perpendicular to the examination surface

    International Nuclear Information System (INIS)

    The most significant result of this study concerns the possibility of detecting artificial planar defects oriented in the perpendicular direction to the surface. By the so-called ''Pulse-echo'' method whatever the codes applied CPFC, ASME, ADPH (RFA) and transducers type used, the detection levels of the largest reflectors (phi 10mm) are well below the respective notation thresholds

  20. Angle-dependent hard X-ray photoemission study of Nb hydride formation in high-pressure supercritical water

    Energy Technology Data Exchange (ETDEWEB)

    Soda, Kazuo, E-mail: j45880a@cc.nagoya-u.ac.jp [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Kondo, Hiroki; Yamaguchi, Kanta; Kato, Masahiko [Department of Quantum Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Shiraki, Tatsuhito; Niwa, Ken; Kusaba, Keiji; Hasegawa, Masashi [Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Xeniya, Kozina; Ikenaga, Eiji [Japan Synchrotron Radiation Research Institute, 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2015-09-15

    Highlights: • Nb hydrides in 10-GPa supercritical water are studied by photoelectron spectroscopy. • The hydride components of the Nb 3d core-level spectra are increased with the depth. • The bulk valence-band spectrum shows a split band due to the Nb–H bond formation. • The hydrides are formed in the bulk and their surfaces are covered with Nb oxides. - Abstract: Nb hydrides formation in 10-GPa supercritical water has been investigated by angle-dependent micro-beam hard X-ray photoemission spectroscopy. In the Nb 3d core-level spectra, Nb hydride components are found in the slightly high binding energy side of the metallic components, and the oxide ones are observed even though little oxides are recognized in X-ray diffraction patterns. Obtained emission-angle dependence of the Nb 3d core-level spectra of Nb hydride specimens shows that the Nb hydride components increase with the emission angle decreased i.e. the sampling depth increased, while the oxide ones decrease. The bulk valence-band spectrum is obtained by decomposing the measured valence-band spectra into a bulk and surface components with use of the emission-angle dependence of the core-level and valence-band spectra; it consists of two bands. This implies the Nb–H chemical bond formation and Nb in an oxidation state, consistent with reported band structure calculations and the observed core-level chemical shifts. Thus it is confirmed by valence-band and core-level photoelectron spectroscopy that the Nb hydrides are formed inside the specimen, irrespective to the well-known high oxidation ability of supercritical water.

  1. Measurement of solidification and melting behavior of resin in injection molding and detection of flaws molded parts by using ultrasonic waves

    International Nuclear Information System (INIS)

    Injection molding of thermoplastics is widely used in many industries. However, it is not so easy to design the mold and to determine the optimal injection conditions. Therefore, a number of CAR mold design software packages for simulating the injection molding process have been developed. In order to confirm the results obtained from CAE, it is necessary to compare the numerical results with the experimental ones. In practice, the filling behavior has been observed with an optical visualization technique, but the solidification behavior of melted resin filled into the cavity has not yet been observed. It has been indirectly detected by measuring the pressure in the mold cavity. On the other hand, the melting behavior of solid resin in the barrel of an infection molding machine has influence on the quality of a molded part. Therefore, it is important to observe the melting behavior of solid resin in the barrel. In this study a method for measuring the solidification behavior in the cavity and the melting behavior in the barrel have been developed by using ultrasonic waves. Moreover, a method of detecting a flaw or a different material included in the molded part has been developed by using ultrasonic waves. Especially, a flaw close to the surface of the molded part can be detected by separating the flaw echo from the surface echo of the molded part. It was determined that the thickness of the solid layer of the melted resin filled into the cavity can be measured by using ultrasonic waves. The melting behavior of the resin on the barrel surface can be observed by measuring the amplitude of the reflected echo on the interface between the barrel and resin. Moreover, the flaw close to the surface of the molded part can be detected by using the ultrasonic waves.

  2. Non-velocity Based Analysis of Passive Ultrasonic Signal for Source Location Detection in Composite Plates: A Pilot Study

    International Nuclear Information System (INIS)

    Acoustic Emission (AE) evaluation is one of the fast growing non-destructive techniques, owing to its ability to reveal in advance of any impending failure of a building structure. This capability makes the so called passive ultrasonic technique a very good tool in structural health monitoring; especially for composite structures. In metallic structures, AE technique is currently well established and able to provide accurate and consistent result. However, in composites, the challenge for a reliable AE results is huge due to the orthotropic behaviour of the materials. The present study investigates the energy attenuation of AE signals in thin composite plate and utilized the attenuation pattern into non-velocity based source location detection. Standard Hsu-Nielsen source location testing was applied on a glass fibre epoxy resin laminate and a single channel AE system was used to acquire AE signals with the support from AEWin software for signal analysis. A linear source location algorithm utilizing AE signals energy attenuation patterns was developed and tested for the composite specimen. The results revealed that the source location algorithm provides reasonably accurate results of source location for glass fibre epoxy resin laminate.

  3. Simultaneous determination of seven fluoroquinolones in royal jelly by ultrasonic-assisted extraction and liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Zhou, Jinhui; Xue, Xiaofeng; Chen, Fang; Zhang, Jinzhen; Li, Yi; Wu, Liming; Chen, Lanzhen; Zhao, Jing

    2009-04-01

    A method for the quantitative determination of seven fluoroquinolone antibacterial agents (FQs) used in beekeeping, viz. ciprofloxacin, norfloxacin, ofloxacin, pefloxacin, danofloxacin, enrofloxacin, and difloxacin, in royal jelly samples was developed on the basis of high performance liquid chromatography with fluorescence detection. Sample preparation included deproteination, ultrasonic-assisted extraction with a mixed inorganic solution of monopotassium phosphate (KH(2)PO(4)) and ethylenediaminetetraacetic acid disodium salt (Na(2)EDTA), and clean-up on a solid-phase extraction cartridge. The extraction procedure was optimized with regard to the amount of inorganic solvent and the duration of sonication for royal jelly as a complicated matrix. Overall recoveries for FQs ranged from 85.9 to 99.1% for royal jelly with standard deviations between 2.79 and 6.27%. Limits of quantification were 2-40 ng/g for seven FQs in royal jelly. A total of 57 real royal jelly samples collected from beekeepers and supermarkets were analyzed. The three most abundant honeybee-use FQs, i. e. ofloxacin, ciprofloxacin, and norfloxacin, were determined in some royal jelly samples in concentrations ranging from 11.9 to 55.6 ng/g. Unexpectedly, however, difloxacin was found at concentrations of about 46.8 ng/g in one sample although it is rarely used in beekeeping. The presented method was successfully applied to quantify FQs in real royal jelly samples. PMID:19306254

  4. Efficiency enhancement and angle-dependent color change in see-through organic photovoltaics using distributed Bragg reflectors

    Science.gov (United States)

    Dong, Wan Jae; Lo, Nhat-Truong; Jung, Gwan Ho; Ham, Juyoung; Lee, Jong-Lam

    2016-03-01

    A distributed Bragg reflector (DBR) is conducted as a bottom reflector in see-through organic photovoltaics (OPVs) with an active layer of poly(3-hexylthiophene) and phenyl-C61-butyric acid methyl ester (P3HT:PCBM). The DBR consists of alternative layers of the high- and low-refractive index materials of Ta2O5 (n = 2.16) and SiO2 (n = 1.46). The DBR selectively reflects the light within a specific wavelength region (490 nm-630 nm) where the absorbance of P3HT:PCBM is maximum. The see-through OPVs fabricated on DBR exhibit efficiency enhancement by 31% compared to the device without DBR. Additionally, the angle-dependent transmittance of DBR is analysed using optical simulation and verified by experimental results. As the incident angle of light increases, peak of reflectance shifts to shorter wavelength and the bandwidth gets narrower. This unique angle-dependent optical properties of DBR allows the facile color change of see-through OPVs.

  5. Ultrasonic detection in concrete structures of damage from sulfate attack%硫酸盐腐蚀混凝土构件损伤检测研究

    Institute of Scientific and Technical Information of China (English)

    张风杰; 袁迎曙; 杜健民

    2011-01-01

    采用化学分析、微观结构观察及超声检测等技术对混凝土腐蚀厚度进行测定,结合连续损伤原理对混凝土均匀腐蚀的损伤度进行了初步定义.提出了以化学分析结果为基准对超声检测混凝土腐蚀厚度结果进行修正的思路,研究了不同腐蚀厚度混凝土的超声检测与化学分析结果之间的关系.结果表明:超声平测法检测腐蚀厚度较小时误差较大(L0<75 mm时),对声速突变测距L0>75 mm时检测结果与化学分析结果相近,表明超声平测法可以用来检测不同介质分界面位置;通过对超声波在不同腐蚀厚度混凝土中的传播速率变化,发现超声声速与混凝土腐蚀层厚度有关,表明随着混凝土腐蚀厚度增加其内部结构密实性降低.%The corrosion thickness of concrete specimens was determined using chemical analysis, micro-structural observations, and an ultrasonic method. A continual damage theory was used to define the extent of concrete destruction. The use of the ultrasonic thickness measurements is proposed as a way of amending these results. The relationship between chemical and ultrasonic methods of corrosion testing was examined. Larger error is observed for ultrasonic penetration testing when the density of corrosion was small (L0< 75 mm). However, for L0 greater than 75 millimeters the ultrasonic and chemical methods give similar results. Hence,ultrasonic penetration testing can be used to locate the interface between solid and corroded concrete. The sound velocity is related to the corrosion density of the concrete. It appears that an increase in corrosion reduces the density of the concrete, which may be detected ultrasonically.

  6. Comparison of ultrasonic reflectometry and FTIR analysis for thermal ageing effect detection for paint films on steel plates

    OpenAIRE

    Augereau, Franck; Zhang, Xin; Laux, Didier; Despaux, Gilles; LECLEZIO, Emmanuel; Fayolle, Bruno; ZAHRA, Yahya; Kuntz, Marc

    2012-01-01

    The aim of this experimental work is to provide a non destructive evaluation tool for quality control on paint films used for industrial purpose after deposition and in operation. The most sensitive conditions have to be found for ultrasonic inspection and the measured acoustic parameters have also to be linked to the state of the complex chemical structure of polymers. Ultrasonic reflectometry is tested to investigate the thermal ageing of epoxy coatings. As function of frequency and inciden...

  7. New experience and methods in ultrasonic testing

    International Nuclear Information System (INIS)

    In addition to the conventional ultrasonic testing, ultrasonic line holography is a significant tool for improved interpretation of measured data. The creep wave scanning head is particularly suited for detecting sub-seam cracks, crack initiation under platings, and terrace-shaped fracture. The ultrasonic holography method also proved to be good for evaluating spot welds of austenitic sheets. (DG)

  8. Measurement of focused ultrasonic fields based on colour edge detection and curve fitting

    Science.gov (United States)

    Zhu, H.; Chang, S.; Yang, P.; He, L.

    2016-03-01

    This paper utilizes firstly both a scanning device and an optic fiber hydrophone to establish a measurement system, and then proposes the parameter measurement of the focused transducer based on edge detection of the visualized acoustic data and curve fitting. The measurement system consists of a water tank with wedge absorber, stepper motors driver, system controller, a focused transducer, an optic fiber hydrophone and data processing software. On the basis of the visualized processing for the original scanned data, the -3 dB beam width of the focused transducer is calculated using the edge detection of the acoustic visualized image and circle fitting method by minimizing algebraic distance. Experiments on the visualized ultrasound data are implemented to verify the feasibility of the proposed method. The data obtained from the scanning device are utilized to reconstruct acoustic fields, and it is found that the -3 dB beam width of the focused transducer can be predicted accurately.

  9. Detection of multiple thin surface cracks using vibrothermography with low-power piezoceramic-based ultrasonic actuator—a numerical study with experimental verification

    Science.gov (United States)

    Parvasi, Seyed Mohammad; Xu, Changhang; Kong, Qingzhao; Song, Gangbing

    2016-05-01

    Ultrasonic vibrations in cracked structures generate heat at the location of defects mainly due to frictional rubbing and viscoelastic losses at the defects. Vibrothermography is an effective nondestructive evaluation method which uses infrared imaging (IR) techniques to locate defects such as cracks and delaminations by detecting the heat generated at the defects. In this paper a coupled thermo-electro-mechanical analysis with the use of implicit finite element method was used to simulate a low power (10 W) piezoceramic-based ultrasonic actuator and the corresponding heat generation in a metallic plate with multiple surface cracks. Numerical results show that the finite element software Abaqus can be used to simultaneously model the electrical properties of the actuator, the ultrasonic waves propagating within the plate, as well as the thermal properties of the plate. Obtained numerical results demonstrate the ability of these low power transducers in detecting multiple cracks in the simulated aluminum plate. The validity of the numerical simulations was verified through experimental studies on a physical aluminum plate with multiple surface cracks while the same low power piezoceramic stack actuator was used to excite the plate and generate heat at the cracks. An excellent qualitative agreement exists between the experimental results and the numerical simulation’s results.

  10. Numerical analysis and noise detection for design optimisation of an ultrasonic transducer

    International Nuclear Information System (INIS)

    The characteristics of a Langevin transducer are studied using a combination of numerical and experimental techniques, which reveal the effect of minor design changes on its performance. The experiments were performed using a microphone and voice-recording software capable of measuring frequencies up to 41 kHz; the obtained signal was analysed in MATLAB. A three-dimensional finite element model of the analysed transducer was also developed in a commercial finite element software ABAQUS/Standard and used for numerical simulations of its response to different excitation conditions. The transducer system was optimised using the results of noise detection and FEA.

  11. Ultrasonic communication in frogs.

    Science.gov (United States)

    Feng, Albert S; Narins, Peter M; Xu, Chun-He; Lin, Wen-Yu; Yu, Zu-Lin; Qiu, Qiang; Xu, Zhi-Min; Shen, Jun-Xian

    2006-03-16

    Among vertebrates, only microchiropteran bats, cetaceans and some rodents are known to produce and detect ultrasounds (frequencies greater than 20 kHz) for the purpose of communication and/or echolocation, suggesting that this capacity might be restricted to mammals. Amphibians, reptiles and most birds generally have limited hearing capacity, with the ability to detect and produce sounds below approximately 12 kHz. Here we report evidence of ultrasonic communication in an amphibian, the concave-eared torrent frog (Amolops tormotus) from Huangshan Hot Springs, China. Males of A. tormotus produce diverse bird-like melodic calls with pronounced frequency modulations that often contain spectral energy in the ultrasonic range. To determine whether A. tormotus communicates using ultrasound to avoid masking by the wideband background noise of local fast-flowing streams, or whether the ultrasound is simply a by-product of the sound-production mechanism, we conducted acoustic playback experiments in the frogs' natural habitat. We found that the audible as well as the ultrasonic components of an A. tormotus call can evoke male vocal responses. Electrophysiological recordings from the auditory midbrain confirmed the ultrasonic hearing capacity of these frogs and that of a sympatric species facing similar environmental constraints. This extraordinary upward extension into the ultrasonic range of both the harmonic content of the advertisement calls and the frog's hearing sensitivity is likely to have co-evolved in response to the intense, predominantly low-frequency ambient noise from local streams. Because amphibians are a distinct evolutionary lineage from microchiropterans and cetaceans (which have evolved ultrasonic hearing to minimize congestion in the frequency bands used for sound communication and to increase hunting efficacy in darkness), ultrasonic perception in these animals represents a new example of independent evolution. PMID:16541072

  12. A Feasibility Study on the Application of Ultrasonic Method for Surface Crack Detection of SiC/SiC Composite Ceramics

    International Nuclear Information System (INIS)

    Nondestructive evaluation(NDE) of ceramic matrix composites is essential for developing reliable ceramics for industrial applications. In the work, C-Scan image analysis has been used to characterize surface crack of SiC ceramics nondestructively. The possibility of detection of surface crack were carried out experimentally by two types of ultrasonic equipment of SDS-win and μ-SDS, and three types of transducer of 25, 50 and 125 MHz. A surface micro-crack of ceramics was not detected by transducer of 25 MHz and 50 MHz. Though the focus method was detected dimly the crack by transducer of 125 MHz, the defocus method could detect the shape of diamond indenter. As a whole, the focus method and the defocus method came to the conclusion that micro crack have a good possibility for detection

  13. Ultrasonic detection of spall damage nucleation under low-velocity repeated impact

    Directory of Open Access Journals (Sweden)

    Watanabe T.

    2012-08-01

    Full Text Available Repeated plate impact testing with impact stress well below the threshold spall-stress (2.6 GPa on medium carbon steel was carried out to the identical target plate by impacting the flyer plate. Occurrence of spall damage under low-velocity repeated impact was evaluated nondestructively with a low frequency scanning acoustic microscope. We observed the spall damage distribution by the B- and C-scan images. In order to initiate the spall damage (voids in a ductile material or cracks in a brittle one the particular value of threshold spall-stress should be exceeded what already belongs to a commonly accepted knowledge. Generally, the spall damage development is dependent on the amplitude and the duration of the stress pulse. If the stress is high and duration is long enough to create tensile failure of material, the voids or cracks nucleate along the spall plane, and consequently, they form macrocracks. Therefore, the spall damage does not create when the first impact stress is less than the threshold spall-stress. However, after the fifth low-velocity repeated impact test, the generation of the spall damage was detected, even if the impact stress (1.1–1.7 GPa was lower than the threshold spall-stress (2.6 GPa.

  14. Ultrasonic quantitative detection of elasticity of jugular vessel wall of female pilots and its application value

    Directory of Open Access Journals (Sweden)

    Long-fang ZHANG

    2011-11-01

    Full Text Available Objective To observe the elasticity of the jugular vessel wall of female aerotransport pilots on active duty,provide a reference for the selection of female pilots,and the prevention and therapy of cardiovascular diseases in female pilots.Methods Using the Echo-Tracking technique,the elastic parameters of the carotid artery were quantitatively detected in nineteen female pilots who were first selected as female astronauts.Twenty male pilots who were selected as astronauts were randomly chosen as the control group.No statistical difference in age and blood pressure between the two groups was found.No history of cardiovascular diseases was recorded,and no abnormal signs were revealed in the results of the physical examination.Electrocardiogram,chest radiography,hepatic and kidney function,and biochemical examination showed normal results.The factors affecting the elasticity of the artery could possibly be avoided for the male pilots except for the fighter pilots or the smokers.Results No statistical difference was found in the clinical and biochemical data between the pilot groups(P > 0.05.As for carotid artery elastic parameters,no statistical difference between the left and right sides of the artery was indicated.The elastic modulus,arterial stiffness index,and pulse wave velocity of the carotid artery wall of the female pilots were significantly lower than those of the male pilots(P < 0.05,and the arterial compliance was significantly higher than that of the male pilots(P < 0.05.Conclusion All of the elastic parameters of the vessel wall of female pilots were better than those of the male pilots.

  15. Automated flaw detection scheme for cast austenitic stainless steel weld specimens using Hilbert-Huang transform of ultrasonic phased array data

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Tariq; Majumdar, Shantanu; Udpa, Lalita [Dept. of Electrical and Comupter Engineering, Michian State University, East Lansing, MI 48824 (United States); Ramuhalli, Pradeep; Crawford, Susan; Diaz, Aaron; Anderson, Michael T. [Pacific Northwest National Laboratory, Richland, WA 99354 (United States)

    2012-05-17

    The objective of this work is to develop processing algorithms to detect and localize flaws using ultrasonic phased-array data. Data was collected on cast austenitic stainless stell (CASS) weld specimens onloan from the U.S. nuclear power industry' Pressurized Walter Reactor Owners Group (PWROG) traveling specimen set. Each specimen consists of a centrifugally cast stainless stell (CCSS) pipe section welded to a statically cst(SCSS) or wrought (WRSS) section. The paper presents a novel automated flaw detection and localization scheme using low frequency ultrasonic phased array inspection singals from the weld and heat affected zone of the based materials. The major steps of the overall scheme are preprocessing and region of interest (ROI) detection followed by the Hilbert-Huang transform (HHT) of A-scans in the detected ROIs. HHT offers time-frequency-energy distribution for each ROI. The Accumulation of energy in a particular frequency band is used as a classification feature for the particular ROI.

  16. Ultrasonic transducer

    International Nuclear Information System (INIS)

    A description is given of an ultrasonic transducer capable of operating at high temperature and comprising a transducer crystal and a coupling piece. This coupling piece is composed of several thin plates, generally triangular in shape, in a material withstanding corrosion and high temperatures, these plates being applied one against the other by pressure. One of the edges of the coupling piece is designed so as to direct towards the junction surfaces of the various plates the ultrasonic waves reflected from the junction between the coupling piece and the piece to which the ultrasonic waves must be transmitted

  17. Ultrasonic tests. Pt. 2

    International Nuclear Information System (INIS)

    After a basic treatment of ultrasonic wave propagation, of the state-of-the-art methods and the technical background in the preceeding part, advanced ultrasonic NDT techniques are presented here. The discussion of new development includes - manipulation systems, - automation of ultrasonic testing methods, documentation and evaluation. In the middle of this part the main problem areas will be discussed: - detection of defects (e.g. in coarse grained structures and welds), - classification of defects (e.g. discrimination between crack-like and volumetric faults), - sizing of defects. Research in the field of acoustical holography, development of probes and phased arrays, electromagnetic acoustic transducers and signal enhancement are the main contributing parts to the report. (orig./RW)

  18. 超声波流量检测新方法研究%Research on New Method for Detection of Ultrasonic Flow

    Institute of Scientific and Technical Information of China (English)

    杨秋菊

    2013-01-01

      This paper analyses the time-difference detection method of ultrasonic flow and proposes a noves signal processing way based on the integral method and zero crossing detection technology, which aims to reduce the power consumption and avoids the complexity of signal processing. Inaddition, the paper also combines the timing procedure design and puts forward a effective measure to achieve low power consumption of ultrasonic flow detection.%  文章通过分析超声波流量的时差式检测方法,创新地采用了基于积分法及过零检测技术,提出了基于此方法的信号处理方式,达到了降低整机功耗的目的,规避了复杂的信号处理。此外,文章还结合了对时序工作方面的设计,提出了一种有效的措施来达到对超声波流量低功耗检测的目的。

  19. Ultrasonic mammography

    International Nuclear Information System (INIS)

    608 women are examined by means of ultrasonic mammography during the period of 1 year. 432 patients were examined with the compound method with the U.I. Octoson, a water tank scanner, and 176 patients with the real time method with a directly connected linear-array-scanner. The following results were obtained at the end of the examination period: In the ultrasonic and also in the X-ray mammogram tumour diameters can be determined with an error rate of +- 30%. In the diagnosing of carcinomas, a significant dependence of the exactness on the sice of the tumour is found for the combination of the five methods tested (clinical examination, X-ray mammography, ultrasonic mammography, thermography, cytology). Classifying the individual methods with regard to their exactness, X-ray mammography ranks in front of ultrasonic mammography. Mastopathic changes in the breast can be screened by means of ultrasonic mammography. The structure of the changes can be determined more exactly than with an X-ray picture which is due to the possibility of differentiating solid and cystic structures. In diagnosing fibro-adenomas and establishing diagnoses on young women with dense gland bodies, ultrasonic mammography is superior to radiology both in the ability of screening a finding of a fibro-adenoma (US=88%, X-ray=75%) and in the possibility of classifying it as ''more benign than malignant''. (orig./MG)

  20. Application and Solution Research of Ultrasonic Defect Detection%超声测缺的应用问题与解决对策研究

    Institute of Scientific and Technical Information of China (English)

    缪群; 韩耀红; 陆津龙

    2000-01-01

    结合上海地区无损检测实测考核中的具体情况,分析了在混凝土浅裂缝和空洞缺陷的超声测试过程中经常遇到的一些问题,对漏判和误判原因进行了评述,并探讨了解决方法%Basing on the NDT examination in Shanghai, authors introduce some problems which we usually meet in the process of ultrasonic detection of such problems as shallow concrete cracks and cavities defects.The reasons of missing detection and wrong detection are analyzed in this article,and some solutions of shallow cracks are also given out in the article.

  1. Defect detection and size estimation in billet from profile of time-of-flight using ultrasonic transmission method with linear scanning

    Science.gov (United States)

    Miyamoto, Ryusuke; Mizutani, Koichi; Ebihara, Tadashi; Wakatsuki, Naoto

    2015-07-01

    In this study, defect detection and size estimation in billet by transmission method with linear scanning were carried out and the validity of the method was evaluated by numerical simulation. In addition, the suitable signal frequency and aperture of transducers were clarified. As a result, the following were found: a defect can be detected, signals with frequencies lower than those generally used in conventional ultrasonic testing (i.e., 0.5-1.5 MHz) are desirable, and the time-of-flight (TOF) deviation Δτ becomes largest when the wavelength at center frequency and the aperture of transducers are comparable. Defect size can be estimated when a single defect exists alone and the defect is not near the surface of a billet. Although defect size estimation becomes difficult when the defect is near the surface of a billet, the defect can be detected by our proposed method.

  2. Angle-dependent XPS study of the mechanisms of 'high-low temperature' activation of GaAs photocathode

    International Nuclear Information System (INIS)

    The surface chemical compositions, atomic concentration percentage and layer thickness after 'high-temperature' single-step activation and 'high-low temperature' two-step activation were obtained using quantitative analysis of angle-dependent X-ray photoelectron spectroscopy (XPS). It was found that compared to single-step activation, the thickness of GaAs-O interface barrier had a remarkable decrease, the degree of As-O bond became much smaller and the Ga-O bond became dominating, and at the same time the thickness of (Cs, O) layer also had a deduction while the ratio of Cs to O had no change after two-step activation. The measured spectral response curves showed that a increase of 29% of sensitivity had been obtained after two-step activation. To explore the inherent mechanisms of influences of the evolution of GaAs(Cs, O) surface layers on photoemission, surface electric barrier models based on the experimental results were built. By calculation of electron escape probability it was found that the decrease of thickness of GaAs-O interface barrier and (Cs, O) layer is the main reasons, which explained why higher sensitivity is achieved after two-step activation than single-step activation

  3. Strong spin-orbit coupling and Zeeman spin splitting in angle dependent magnetoresistance of Bi2Te3

    International Nuclear Information System (INIS)

    We have studied angle dependent magnetoresistance of Bi2Te3 thin film with field up to 9 T over 2–20 K temperatures. The perpendicular field magnetoresistance has been explained by the Hikami-Larkin-Nagaoka theory alone in a system with strong spin-orbit coupling, from which we have estimated the mean free path, the phase coherence length, and the spin-orbit relaxation time. We have obtained the out-of-plane spin-orbit relaxation time to be small and the in-plane spin-orbit relaxation time to be comparable to the momentum relaxation time. The estimation of these charge and spin transport parameters are useful for spintronics applications. For parallel field magnetoresistance, we have confirmed the presence of Zeeman effect which is otherwise suppressed in perpendicular field magnetoresistance due to strong spin-orbit coupling. The parallel field data have been explained using both the contributions from the Maekawa-Fukuyama localization theory for non-interacting electrons and Lee-Ramakrishnan theory of electron-electron interactions. The estimated Zeeman g-factor and the strength of Coulomb screening parameter agree well with the theory. Finally, the anisotropy in magnetoresistance with respect to angle has been described by the Hikami-Larkin-Nagaoka theory. This anisotropy can be used in anisotropic magnetic sensor applications.

  4. Combination probe for optically assisted ultrasonic velocity-change imaging aimed at detecting unstable blood vessel plaque

    Science.gov (United States)

    Tanigawa, Shohei; Mano, Kazune; Wada, Kenji; Matsunaka, Toshiyuki; Horinaka, Hiromichi

    2016-04-01

    Blood vessel plaque with a large lipid core is at risk of becoming thrombus and is likely to induce acute heart disease. To prevent this, it is necessary to determine not only the plaque's size but also its chemical composition. We, therefore, made the prototype of a combination probe to diagnose carotid artery plaque. It is used to differentiate propagation characteristics between light spectra and ultrasonic images. By propagating light and ultrasound along a common direction, it is possible to effectively warm the diagnosis domain. Moreover, the probe is thought to be compact and be easy to use for diagnosing human carotid artery plaque. We applied the combination probe to a carotid artery phantom with a lipid area and obtained an image of the ultrasonic velocity change in the fatty area.

  5. Angle-dependent strong-field molecular ionization rates with tuned range-separated time-dependent density functional theory.

    Science.gov (United States)

    Sissay, Adonay; Abanador, Paul; Mauger, François; Gaarde, Mette; Schafer, Kenneth J; Lopata, Kenneth

    2016-09-01

    Strong-field ionization and the resulting electronic dynamics are important for a range of processes such as high harmonic generation, photodamage, charge resonance enhanced ionization, and ionization-triggered charge migration. Modeling ionization dynamics in molecular systems from first-principles can be challenging due to the large spatial extent of the wavefunction which stresses the accuracy of basis sets, and the intense fields which require non-perturbative time-dependent electronic structure methods. In this paper, we develop a time-dependent density functional theory approach which uses a Gaussian-type orbital (GTO) basis set to capture strong-field ionization rates and dynamics in atoms and small molecules. This involves propagating the electronic density matrix in time with a time-dependent laser potential and a spatial non-Hermitian complex absorbing potential which is projected onto an atom-centered basis set to remove ionized charge from the simulation. For the density functional theory (DFT) functional we use a tuned range-separated functional LC-PBE*, which has the correct asymptotic 1/r form of the potential and a reduced delocalization error compared to traditional DFT functionals. Ionization rates are computed for hydrogen, molecular nitrogen, and iodoacetylene under various field frequencies, intensities, and polarizations (angle-dependent ionization), and the results are shown to quantitatively agree with time-dependent Schrödinger equation and strong-field approximation calculations. This tuned DFT with GTO method opens the door to predictive all-electron time-dependent density functional theory simulations of ionization and ionization-triggered dynamics in molecular systems using tuned range-separated hybrid functionals. PMID:27608987

  6. 超声检测中收发波形的数字化处理%Digital Process of Transceiver in Ultrasonic Detect System

    Institute of Scientific and Technical Information of China (English)

    王义

    2011-01-01

    时差法超声检测是通过对发射波与第一次回波之间的时差进行计时进而求得探测目标位置的一种方法。本文以CPLD(Complex Programmable Logic Device)为基础,结合MCU(Micro Control Unit)的处理特点,介绍了发射驱动信号与接收回波检测的数字化处理方法与程序设计,简化了电路设计,加大了控制的灵活性。%With counting the time interval from transmitting pulse to the first echo, ultrasonic detect system can detect the object. This paper introduces how to produce digital signal to drive the transmitter and convert received analog echo signal to digital sign

  7. Final Assessment of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Michael T.; Diaz, Aaron A.; Cinson, Anthony D.; Crawford, Susan L.; Prowant, Matthew S.; Doctor, Steven R.

    2014-03-24

    PNNL conducted a technical assessment of the NDE issues and protocols that led to missed detections of several axially oriented flaws in a steam generator primary inlet dissimilar metal weld at North Anna Power Station, Unit 1 (NAPS-1). This particular component design exhibits a significant outside-diameter (OD) taper that is not included as a blind performance demonstration mock-up within the industry’s Performance Demonstration Initiative, administered by EPRI. For this reason, the licensee engaged EPRI to assist in the development of a technical justification to support the basis for a site-specific qualification. The service-induced flaws at NAPS-1 were eventually detected as a result of OD surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the dissimilar metal weld. A total of five axially oriented flaws were detected in varied locations around the weld circumference. The field volumetric examination that was conducted at NAPS-1 was a non-encoded, real-time manual ultrasonic examination. PNNL conducted both an initial assessment, and subsequently, a more rigorous technical evaluation (reported here), which has identified an array of NDE issues that may have led to the subject missed detections. These evaluations were performed through technical reviews and discussions with NRC staff, EPRI NDE Center personnel, industry and ISI vendor personnel, and ultrasonic transducer manufacturers, and laboratory tests, to better understand the underlying issues at North Anna.

  8. Ultrasonic neuromodulation

    Science.gov (United States)

    Naor, Omer; Krupa, Steve; Shoham, Shy

    2016-06-01

    Ultrasonic waves can be non-invasively steered and focused into mm-scale regions across the human body and brain, and their application in generating controlled artificial modulation of neuronal activity could therefore potentially have profound implications for neural science and engineering. Ultrasonic neuro-modulation phenomena were experimentally observed and studied for nearly a century, with recent discoveries on direct neural excitation and suppression sparking a new wave of investigations in models ranging from rodents to humans. In this paper we review the physics, engineering and scientific aspects of ultrasonic fields, their control in both space and time, and their effect on neuronal activity, including a survey of both the field’s foundational history and of recent findings. We describe key constraints encountered in this field, as well as key engineering systems developed to surmount them. In closing, the state of the art is discussed, with an emphasis on emerging research and clinical directions.

  9. Ultrasonication-assisted one-step self-assembly preparation of biocompatible fluorescent-magnetic nanobeads for rare cancer cell detection

    Science.gov (United States)

    Guo, Shan; Chen, Yu-Qi; Lu, Ning-Ning; Wang, Xue-Ying; Xie, Min; Sui, Wei-Ping

    2014-12-01

    Multifunctional nanomaterials simultaneously possessing attractive properties, such as strong fluorescent intensity, excellent superparamagnetic behavior, easy modification and good biocompatibility, are always desired in a wide range of applications. In this work, we present a facile ultrasonication-assisted one-step self-assembly strategy for the fabrication of smart fluorescent-magnetic nanobeads (FMNBs) without using a matrix. Via one-step ultrasonication, organic-soluble superparamagnetic nanoparticles (MNPs) and quantum dots (QDs) were automatically encapsulated by amphiphilic (2-hydroxyl-3-dodecanoxyl) propylcarboxymethylchitosans (HDP-CMCHSs) through hydrophobic interaction to form hydrophilic FMNBs, presenting a good QD fluorescent property and a strong MNP magnetic response. The outer surface of the FMNBs was derived from natural biopolymer chitosans, enabling FMNBs with good biocompatibility and convenience for biological modification. As-prepared FMNBs can be easily modified with streptavidin, facilitating bioconjugation with biotin-labeled human epidermal growth factor (hEGF). hEGF-functionalized FMNBs are able to specifically recognize and capture rare target cells spiked in white blood cells, and the recovered cells can be further cultured for a long time. All of these excellent properties make nanobeads promising for circulating tumor cell (CTC) detection.

  10. Ultrasonication-assisted one-step self-assembly preparation of biocompatible fluorescent-magnetic nanobeads for rare cancer cell detection

    International Nuclear Information System (INIS)

    Multifunctional nanomaterials simultaneously possessing attractive properties, such as strong fluorescent intensity, excellent superparamagnetic behavior, easy modification and good biocompatibility, are always desired in a wide range of applications. In this work, we present a facile ultrasonication-assisted one-step self-assembly strategy for the fabrication of smart fluorescent-magnetic nanobeads (FMNBs) without using a matrix. Via one-step ultrasonication, organic-soluble superparamagnetic nanoparticles (MNPs) and quantum dots (QDs) were automatically encapsulated by amphiphilic (2-hydroxyl-3-dodecanoxyl) propylcarboxymethylchitosans (HDP-CMCHSs) through hydrophobic interaction to form hydrophilic FMNBs, presenting a good QD fluorescent property and a strong MNP magnetic response. The outer surface of the FMNBs was derived from natural biopolymer chitosans, enabling FMNBs with good biocompatibility and convenience for biological modification. As-prepared FMNBs can be easily modified with streptavidin, facilitating bioconjugation with biotin-labeled human epidermal growth factor (hEGF). hEGF-functionalized FMNBs are able to specifically recognize and capture rare target cells spiked in white blood cells, and the recovered cells can be further cultured for a long time. All of these excellent properties make nanobeads promising for circulating tumor cell (CTC) detection. (paper)

  11. Ultrasonic transducer

    International Nuclear Information System (INIS)

    An ultrasonic transducer suitable for use up to a temperature of about 6000C comprises a stainless steel casing containing a lithium niobate piezoelectric element and a backing material of a powder which provides a partial pressure of oxygen and thereby prevents deterioration of the element by oxygen loss or contamination. The powder might be of lithium niobate or magnesia. (author)

  12. Ultrasonic transducer

    International Nuclear Information System (INIS)

    The invention concerns an ultrasonic piezoelectric transducer fitted in sealed boxes for use in liquid sodium cooled fast nuclear reactors. These transducers are immersed in the sodium. The box is so constructed that its enables a removable connexion to be made between the transducer box itself and the connector

  13. Ultrasonic wall thickness measurement without coupling liquid

    International Nuclear Information System (INIS)

    If the material measured is part of the ultrasonic transducer, then one can do without the usual coupling liquid for ultrasonic measurement of wall thickness. Measuring equipment works on the basis of this electro-dynamic ultrasonic transducer, which has been developed to check the wall thickness (3 to 30 mm) of steel pipes with outside diameters of 25 to 180 mm. Double errors and local changes of wall thickness can be detected. (orig.)

  14. Ultrasonic Transducer Irradiation Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Daw, Joshua [Idaho National Lab. (INL), Idaho Falls, ID (United States); Palmer, Joe [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ramuhalli, Pradeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Keller, Paul [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Montgomery, Robert [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chien, Hual-Te [Argonne National Lab. (ANL), Argonne, IL (United States); Kohse, Gordon [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States); Tittmann, Bernhard [Pennsylvania State Univ., University Park, PA (United States); Reinhardt, Brian [Pennsylvania State Univ., University Park, PA (United States); Rempe, Joy [Rempe and Associates, Idaho Falls, ID (United States)

    2015-02-01

    Ultrasonic technologies offer the potential for high-accuracy and -resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other ongoing efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. For this reason, the Pennsylvania State University (PSU) was awarded an ATR NSUF project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2. The goal of this research is to characterize and demonstrate magnetostrictive and piezoelectric transducer operation during irradiation, enabling the development of novel radiation-tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. To date, one piezoelectric

  15. Irradiation Testing of Ultrasonic Transducers

    International Nuclear Information System (INIS)

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of numerous parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. To address this need, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2 (E> 0.1 MeV). This test will be an instrumented lead test; and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. By characterizing magnetostrictive and piezoelectric transducer survivability during irradiation, test results will enable the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. (authors)

  16. Ultrasonic Transducer Irradiation Test Results

    International Nuclear Information System (INIS)

    Ultrasonic technologies offer the potential for high-accuracy and -resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other ongoing efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. For this reason, the Pennsylvania State University (PSU) was awarded an ATR NSUF project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2. The goal of this research is to characterize and demonstrate magnetostrictive and piezoelectric transducer operation during irradiation, enabling the development of novel radiation-tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. To date, one piezoelectric transducer and two

  17. Digital image correlation, acoustic emission and ultrasonic pulse velocity for the detection of cracks in the concrete buffer of the Belgian nuclear supercontainer

    International Nuclear Information System (INIS)

    The long term management of high-level and heat emitting radioactive waste is a worldwide concern, as it directly influences the environment and future generations. To address this issue, the Belgian Agency for Radioactive Waste and Enriched Fissile Materials has come up with the conceptual design of a massive concrete structure called Supercontainer. The feasibility to construct these structures is being evaluated through a number of scaled models that are tested using classical as well as state of the art measurement techniques. In the current paper, the results obtained from the simultaneous application of the Digital Image Correlation (DIC), the Acoustic Emission (AE) and the Ultrasonic Pulse Velocity (UPV) nondestructive testing techniques on the second scaled model for the detection and monitoring of cracks will be presented.

  18. Life Detection and Characterization of Subsurface Ice and Brine in the McMurdo Dry Valleys Using an Ultrasonic Gopher: A NASA ASTEP Project

    Science.gov (United States)

    Doran, P. T.; Bar-Cohen, Y.; Fritsen, C.; Kenig, F.; McKay, C. P.; Murray, A.; Sherrit, S.

    2003-01-01

    Evidence for the presence of ice and fluids near the surface of Mars in both the distant and recent past is growing with each new mission to the Planet. One explanation for fluids forming springlike features on Mars is the discharge of subsurface brines. Brines offer potential refugia for extant Martian life, and near surface ice could preserve a record of past life on the planet. Proven techniques to get underground to sample these environments, and get below the disruptive influence of the surface oxidant and radiation regime, will be critical for future astrobiology missions to Mars. Our Astrobiology for Science and Technology for Exploring Planets (ASTEP) project has the goal to develop and test a novel ultrasonic corer in a Mars analog environment, the McMurdo Dry valleys, Antarctica, and to detect and describe life in a previously unstudied extreme ecosystem; Lake Vida (Fig. 1), an ice-sealed lake.

  19. Digital image correlation, acoustic emission and ultrasonic pulse velocity for the detection of cracks in the concrete buffer of the Belgian nuclear supercontainer

    Energy Technology Data Exchange (ETDEWEB)

    Iliopoulos, Sokratis; Tsangouri, Eleni; Aggelis, Dimitrios G.; Pyl, Lincy [Vrije Univ., Brussels (Belgium). Dept. of Mechanics of Materials and Constructions; Vantomme, John [Vrije Univ., Brussels (Belgium). Dept. of Mechanics of Materials and Constructions; Royal Military Academy, Brussels (Belgium). Civil and Material Engineering Dept.; Marcke, Philippe van [ONDRAF/NIRAS (Belgium); Areias, Lou [EURIDICE GIE/SCK.CEN, Mol (Belgium); Vrije Univ., Brussels (Belgium). Dept. of Mechanics of Materials and Constructions

    2014-11-01

    The long term management of high-level and heat emitting radioactive waste is a worldwide concern, as it directly influences the environment and future generations. To address this issue, the Belgian Agency for Radioactive Waste and Enriched Fissile Materials has come up with the conceptual design of a massive concrete structure called Supercontainer. The feasibility to construct these structures is being evaluated through a number of scaled models that are tested using classical as well as state of the art measurement techniques. In the current paper, the results obtained from the simultaneous application of the Digital Image Correlation (DIC), the Acoustic Emission (AE) and the Ultrasonic Pulse Velocity (UPV) nondestructive testing techniques on the second scaled model for the detection and monitoring of cracks will be presented.

  20. Ultrasonic Transmission Detection Techniques for Large Complex Curved Surface of Composite Material%大型曲面复合材料超声检测技术

    Institute of Scientific and Technical Information of China (English)

    徐春广; 王洪博; 肖定国

    2013-01-01

    In this paper,the detection of common defects such as inclusion ,void and delamination for large -scaled curved composite material is studied .The principle for transmission method is focused on introducing .Moreover ,the results of the C-Scan experiment for different size defects of different thickness carbon -fiber composite supported the opinion a-bove.The technology of trajectory planning and motion control for twin -robot defects detect of various curved composite sample using ultrasonic transmission method is also discussed .An ultrasonic NDT system is developed for testing large -scaled curved composite components used in aerospace and other fields .It will be very significant for our nondestructive tes-ting work.%针对大型曲面复合材料常见夹杂、孔洞、分层等缺陷的检测需求,阐述了超声透射法检测的测量原理,对不同厚度碳纤维复合材料不同孔径大小的缺陷进行了超声C扫描实验,验证了方法的可行性。结合双机械手的运动轨迹规划和控制开展了空间任意曲面复合材料工件的超声透射检测技术研究,并研制了双机械手超声透射无损检测系统,对于航空航天等领域使用的大型曲面复合材料构件的无损检测有着重要的意义。

  1. 环焊缝超声检测缺陷检出率问题的研究%Research on the Defect Detection Rate of Circumferential Weld Ultrasonic Testing

    Institute of Scientific and Technical Information of China (English)

    魏振宝; 罗全意

    2012-01-01

    The majority of oil-gas gathering and transportation pipeline is thin wall, detection surface is curved surface, which locate in the open and easily be affected by the environment. The undetected defect existed in ultrasonic detection, through practicing and observing the ultrasonic detection process, it put forward to improve the ultrasonic testing process from several aspects, such as probe, scanning ways, test block and reference block for calibration and etc., in order to enhance defect detection rate of ultrasonic testing. This study will provide certain guide for improving ultrasonic detection quality of oil-gas gathering and transportation pipeline site welding.%针对油气集输管道多为薄壁管、探伤面为曲面且多在野外易受环境影响等特点,对超声波检测时存在的管道缺陷漏检情况,通过在现场超声检测工艺的实践和观察,从探头、扫查方式、用于校准的标准试块和对比试块等方面来改进超声检测工艺,从而达到提高超声检测缺陷检出率的目的.研究结果对于提高油气集输管道现场焊接的超声检测质量具有一定的指导意义.

  2. Unified Ultrasonic/Eddy-Current Data Acquisition

    Science.gov (United States)

    Chern, E. James; Butler, David W.

    1993-01-01

    Imaging station for detecting cracks and flaws in solid materials developed combining both ultrasonic C-scan and eddy-current imaging. Incorporation of both techniques into one system eliminates duplication of computers and of mechanical scanners; unifies acquisition, processing, and storage of data; reduces setup time for repetitious ultrasonic and eddy-current scans; and increases efficiency of system. Same mechanical scanner used to maneuver either ultrasonic or eddy-current probe over specimen and acquire point-by-point data. For ultrasonic scanning, probe linked to ultrasonic pulser/receiver circuit card, while, for eddy-current imaging, probe linked to impedance-analyzer circuit card. Both ultrasonic and eddy-current imaging subsystems share same desktop-computer controller, containing dedicated plug-in circuit boards for each.

  3. Ultrasonic tests. Pt. 1

    International Nuclear Information System (INIS)

    Nondestructive testing (NDT) plays an important part in the field of nuclear power plants operation. The report is concentrated to the primary loop components' ultrasonic NDT. It includes inspection techniques used during fabrication and in service. While a second part is dealing with advanced NDT methods, this first presentation introduces into the variety of ultrasonic testing procedures. After a treatment of the physical background the appropriate choice of equipment and techniques in respect of material, geometry and accessibility will be discussed. The state-of-the-art for detection, location, normalization, classification and sizing of defects will be presented. Finally, evaluation of faults and accept/reject criteria (e.g. based on fracture mechanics) together with the qualification of NDE personnel are concluding the contribution. (orig./RW)

  4. 小直径薄壁焊管超声波和射线检测对比%Comparison Between Ultrasonic and Radiographic Detection of Small Size Thin Wall Thickness Welded Pipe

    Institute of Scientific and Technical Information of China (English)

    王冬林; 卫栋; 田新新; 李昱坤; 雷凌云; 巨敬伟

    2015-01-01

    In this article, it briefly introduced the characteristics and the testing difficulties of the small diameter thin wall thickness welded pipe, then analyzed two detection methods, the ultrasonic and radiographic detection, and summarized the choice of the key parameters for ultrasonic and radiographic detection. Finally, two kinds of detection methods are compared;the results indicated that the detection rate of radiographic test is higher for volume type defect, and the detection rate of ultrasonic test is higher for area defects;it is very difficult to accurately determine the position and size of defects in workpiece thickness direction for radiographic detection, this problem did not exist in ultrasonic test. Radiographic detection is more suitable for thin wall thickness workpiece.%简要介绍了小直径薄壁焊管的特点及检测存在难点。对小直径薄壁焊管的超声和射线检测进行了重点分析,总结了超声和射线检测时各重点参数的选择原则。最后对两种检测方法进行了比较。结果表明,射线检测对体积型缺陷的检出率较高,而超声检测对面积性缺陷的检出率较高;射线检测很难精确确定缺陷在工件厚度方向的位置和尺寸,而超声检测不存在此问题;射线检测比超声检测更适宜薄壁工件的检测。

  5. Analysis of field-angle dependent specific heat in unconventional superconductors: A comparison between Doppler-shift method and Kramer-Pesch approximation

    International Nuclear Information System (INIS)

    We theoretically discuss the magnetic-field-angle dependence of the zero-energy density of states (ZEDOS) in superconductors. Point-node and line-node superconducting gaps on spherical and cylindrical Fermi surfaces are considered. The Doppler-shift (DS) method and the Kramer-Pesch approximation (KPA) are used to calculate the ZEDOS. Numerical results show that consequences of the DS method are corrected by the KPA.

  6. Ultrasonic imaging of projected components of PFBR

    International Nuclear Information System (INIS)

    Highlights: ► Under sodium ultrasonic scanner in PFBR is for detecting protruding objects. ► Feasibility study for detecting Absorber rods and its drive mechanisms. ► Developed in-house PC based ultrasonic imaging system. ► Different case studies were carried out on simulated ARDM's. ► Implemented the experimental results to PFBR application. -- Abstract: The 500 MWe, sodium cooled, Prototype Fast Breeder Reactor (PFBR) is under advanced stage of construction at Kalpakkam in India. Opacity of sodium restricts visual inspection of components immersed in sodium by optical means. Ultrasonic wave passes through sodium hence ultrasonic techniques using under sodium ultrasonic scanners are developed to obtain under sodium images. The main objective of such an Under Sodium Ultrasonic Scanner (USUSS) for Prototype Fast Breeder Reactor (PFBR) is to detect and ensure that no core Sub Assembly (SA) or Absorber Rod or its Drive Mechanism is protruded in the above core plenum before starting the fuel handling operation. Hence, it is necessary to detect and locate the object, if it is protruding the above core plenum. To study the feasibility of detecting the absorber rods and their drive mechanisms using direct ultrasonic imaging technique, experiments were carried out for different orientations and profiles of the projected components in a 5 m diameter water tank. The in-house developed PC based ultrasonic scanning system is used for acquisition and analysis of data. The pseudo three dimensional color images obtained are discussed and the results are applicable for PFBR. This paper gives the details of the features of the absorber rods and their drive mechanisms, their orientation in the reactor core, experimental setup, PC based ultrasonic scanning system, ultrasonic images and the discussion on the results

  7. Copper clean-up procedure for ultrasonic extraction and analysis of pyrethroid and phenylpyrazole pesticides in sediments by gas chromatography-electron capture detection

    International Nuclear Information System (INIS)

    A rapid ultrasonic extraction method coupled with a heated-copper clean-up procedure for removing interfering constituents was developed for analyzing pyrethroid and phenylpyrazole pesticides in sediments. Incubation of the 60 mL extract with 12 g copper granules at 60 oC for 2 h was determined to be the optimal conditions for removing the interfering constituents. Eleven pyrethroid and phenylpyrazole pesticides were spiked into sediment samples to determine the effectiveness of the ultrasonic extraction method. The average recoveries of pyrethroids and phenylpyrazoles in sediment at 4 oC storage on day 0, 1, 7, 14, and 21 ranged from 98.6 to 120.0%, 79.2 to 116.0%, 85.0 to 119.7%, 93.6 to 118.7%, and 92.1 to 118.2%, respectively, with all percent relative standard deviations less than 10% (most oC. Recoveries of the pesticides ranged from 98.6% to 120.0% for lowest fortification level (2-16 μg kg-1), from 97.8% to 117.9% for middle fortification level (10-80 μg kg-1), and from 94.3% to 118.1% for highest fortification level (20-160 μg kg-1). Relative standard deviations of pesticide recoveries were usually less than 7%. Method detection limits of target pesticides ranged from 0.22 μg kg-1 to 3.72 μg kg-1. Furthermore, field sediment samples collected from four residential lakes during a three-month monitoring period were analyzed to evaluate the effectiveness of this method. Bifenthrin was detected in all of sediment samples (highest concentration 260.33 ± 41.71 μg kg-1, lowest concentration 5.68 ± 0.38 μg kg-1), and fipronil sulfone was detected at least once in sediment samples collected from three sites with concentrations ranging from 1.73 ± 0.53 to 7.53 ± 0.01 μg kg-1. - Highlights: → A rapid extraction and copper-based clean-up method was developed. → Recoveries after storage at 4 oC for 21 d ranged from 79.2 to 120.0%. → Percent relative standard deviations less than 10% (most -1 to 3.72 μg kg-1.

  8. Copper clean-up procedure for ultrasonic extraction and analysis of pyrethroid and phenylpyrazole pesticides in sediments by gas chromatography-electron capture detection.

    Science.gov (United States)

    Wu, Jun; Lin, Youjian; Lu, Jian; Wilson, Chris

    2011-08-15

    A rapid ultrasonic extraction method coupled with a heated-copper clean-up procedure for removing interfering constituents was developed for analyzing pyrethroid and phenylpyrazole pesticides in sediments. Incubation of the 60 mL extract with 12 g copper granules at 60 °C for 2h was determined to be the optimal conditions for removing the interfering constituents. Eleven pyrethroid and phenylpyrazole pesticides were spiked into sediment samples to determine the effectiveness of the ultrasonic extraction method. The average recoveries of pyrethroids and phenylpyrazoles in sediment at 4 °C storage on day 0, 1, 7, 14, and 21 ranged from 98.6 to 120.0%, 79.2 to 116.0%, 85.0 to 119.7%, 93.6 to 118.7%, and 92.1 to 118.2%, respectively, with all percent relative standard deviations less than 10% (most sediment during sediment aging at 4 °C. Recoveries of the pesticides ranged from 98.6% to 120.0% for lowest fortification level (2-16 μg kg⁻¹), from 97.8% to 117.9% for middle fortification level (10-80 μg kg⁻¹), and from 94.3% to 118.1% for highest fortification level (20-160 μg kg⁻¹). Relative standard deviations of pesticide recoveries were usually less than 7%. Method detection limits of target pesticides ranged from 0.22 μg kg⁻¹ to 3.72 μg kg⁻¹. Furthermore, field sediment samples collected from four residential lakes during a three-month monitoring period were analyzed to evaluate the effectiveness of this method. Bifenthrin was detected in all of sediment samples (highest concentration 260.33±41.71 μg kg⁻¹, lowest concentration 5.68±0.38 μg kg⁻¹, and fipronil sulfone was detected at least once in sediment samples collected from three sites with concentrations ranging from 1.73±0.53 to 7.53±0.01 μg kg⁻¹. PMID:21684581

  9. Ultrasonic Testing of Metallic Uranium

    International Nuclear Information System (INIS)

    The development of ultrasonic testing and the results of routine inspection on cast billets and rolled rods for JRR-3 fuel-elements are described. The reactor is a domestic made, heavy-water-moderated and cooled, research reactor of 10 MW capacity, with aluminium clad metallic uranium fuel-elements. Cast billets of 3-in diam. were rolled to rods of 1-in diam. Ultrasonic testing was applied for detecting internal voids and cracks and for evaluating random orientation and grain size after heat treatment. The ultrasonic testing of uranium was very difficult because of its high acoustic impedance, and the high sensitivity of the transducers and special beam mask were necessary for the water-immersed transmission method. A set of brass billets with artificial defects was used as the standard. During the development of these standards, several kinds of Cu-Zn alloy were examined for their acoustic properties. Any internal defects greater than 2 mm and 0.5 mm equivalent diameter were rejected in the case of billets and rolled rods respectively. Two billets which included typical voids were rolled to size, and ultrasonic testing and radiography with Betatron were carried out at several stages to find the behaviour of the voids during fabrication. The attenuation of ultrasonic waves is affected by the grain size, and is particularly large if the ultrasonic wave-length is comparable to the grain size.- This was used for the detection of unsatisfactory heat treatment. The ultrasonic wave-speed is different in the parallel and perpendicular rolling directions in as-rolled state. This difference decreased as the temperature of heat treatment is increased; however, a small difference was observed in a beta-quenched specimen, and real acoustic isotropy was obtained by gamma-quenching. (author)

  10. The Study of T-beam Thickness Detection Method Based on Ultrasonic Velocity Measurement%基于超声波法的T梁厚度检测方法研究

    Institute of Scientific and Technical Information of China (English)

    谢盛明; 汪继文; 詹小丽; 姜维; 邵华

    2015-01-01

    In order to do an express test for bridge slab thickness, a research was carried out on detection method of thickness of typical T-beam on bridge by ultrasonic.The detection precision of this detection method was also analyzed in this paper.The results indicate that the maximum measurement error of T-beam diaphragm by ul-trasonic is 3.5%and the maximum measurement error of T-beam web is 16.4%.According to the test results by ultrasonic velocity measurement, this paper focuses on the problem of ultrasonic measurement on bridge slab thick-ness and proposes accuracy correction of ultrasonic velocity measurement on bridge slab thickness.Research results show that ultrasonic velocity measurement on bridge slab thickness has superiority while still existing drawbacks. The difficult and key points of bridge slab thickness test by ultrasonic are how to select positions quickly and im-prove the precision of data processing.%为快速测试桥梁梁板厚度,本研究运用超声波法对典型桥梁T梁梁板厚度检测方法进行研究,并对其检测方法的检测精度进行分析。研究发现超声波测量T梁横隔板边缘测量误差最大为3.5%,T梁中腹板超声波测量误差最大为20%。根据超声波法的测试结果,提出了超声波测试桥梁梁板精度修正的处理方法。研究结果表明超声波在桥梁梁板厚度测试中具有优越性的同时也存在一些问题,如何克服超声波梁板厚度测试快速定点及测试结果数据处理提高精度是超声波梁板厚度测试的难点和关键。

  11. Modern ultrasonic flowmeters

    Science.gov (United States)

    Gurevich, V. M.; Truman, S. G.

    1986-01-01

    The current status of ultrasonic flowmeters were reviewed on the basis of materials published in the Soviet Union and elsewhere. The following advantages of ultrasonic flowmeters over earlier instruments are cited. A comparative analysis is made of the design methods employed in ultrasonic flowmeters. The evolution of ultrasonic flowmetering is traced from the first generation and trends in their development are analyzed.

  12. Ultrasonic Interferometers Revisited

    Science.gov (United States)

    Greenslade, Thomas B., Jr.

    2007-01-01

    I have been tinkering with ultrasonic transducers once more. In earlier notes I reported on optics-like experiments performed with ultrasonics, described a number of ultrasonic interferometers, and showed how ultrasonic transducers can be used for Fourier analysis. This time I became interested in trying the technique of using two detectors in…

  13. 超声波探伤中对焊缝厚度变化的参数修正%Parameter Correction of Weld Thickness Variation on Ultrasonic Flaw Detection

    Institute of Scientific and Technical Information of China (English)

    胡细超; 朱星星

    2014-01-01

    During the ultrasonic flaw detection on unequal thickness weld,due to uneven thickness,the ultrasonic testing instrument data read from ultrasonic flaw detection instrument were not accurate for the localization of weld defect. Through kinds of unequal thickness of weld on the different repeated tests, the direct wave and primary reflection tests were analyzed and calculated,and the data conversion were completed,ensured accurate detection on unequal thickness weld.%对不等厚焊缝进行超声波探伤时,由于其厚度不均匀,从超声波探伤仪器上读出的数据不能准确地对焊缝缺陷进行定位。通过对各种不同的不等厚焊缝反复测试,分别对直射波、一次反射波进行分析计算,并完成相关数据转换,保证不等厚焊缝的准确检出。

  14. 电磁超声兰姆波的无损探伤技术%Electromagnetic Ultrasonic Lamb Wave Defect Detection of Metal

    Institute of Scientific and Technical Information of China (English)

    杨理践; 梁震; 高松巍

    2012-01-01

    针对金属薄板的缺陷检测问题,进行了电磁超声兰姆波无损探伤技术的研究.基于兰姆波的频散特性,推导出了兰姆波各模式相(群)速度关于线圈间距、频厚积及激励频率的表达式,确定了电磁超声换能器的结构参数.设计了一种DDS与FPGA相结合,产生串码、频率可调的脉冲激励信号串发生电路,利用H桥放大电路对激励信号进行了升压处理,并对激励线圈进行了阻抗匹配.试验结论表明:永磁铁与激励线圈的不同组合形式可以分别在铁磁性和非铁磁性金属薄板中激发出兰姆波.研制的功率放大电路及信号处理电路能够在金属薄板中激发出高性能的兰姆波并实现稳定接收,具有较高的信噪比,能够实现对金属薄板的无损探伤.%For the sheet metal defect detection problem, advanced the electromagnetic ultrasonic Lamb wave nondestructive testing technology research. Based on the dispersion characteristics of Lamb waves, derived out the model of the Lamb wave phase ( group) velocity of the coil spacing, frequency and excitation frequency thickness product expression and determine the electromagnetic ultrasonic transducer structure parameters. Design a DDS and FPGA combined generating circuit, which can generate string of code, adjustable pulse frequency excitation signal string, Used the H-bridge amplifier circuit excitation signal for the boost treatment and then impedance matched the excitation coil. Experiment concluded shown, different form of permanent magnet and excitation coils combination can respectively stimulate Lamb in the ferromagnetic and non-ferromagnetic metal sheet. Developed power amplifier circuit and signal processing circuit can stimulate high-performance in sheet metal and realize stable reception, has a high signal to noise ratio and can execute Non-destructive testing of metal sheet.

  15. Copper clean-up procedure for ultrasonic extraction and analysis of pyrethroid and phenylpyrazole pesticides in sediments by gas chromatography-electron capture detection

    Energy Technology Data Exchange (ETDEWEB)

    Wu Jun; Lin Youjian; Lu Jian; Wilson, Chris, E-mail: pcwilson@ufl.edu

    2011-08-15

    A rapid ultrasonic extraction method coupled with a heated-copper clean-up procedure for removing interfering constituents was developed for analyzing pyrethroid and phenylpyrazole pesticides in sediments. Incubation of the 60 mL extract with 12 g copper granules at 60 {sup o}C for 2 h was determined to be the optimal conditions for removing the interfering constituents. Eleven pyrethroid and phenylpyrazole pesticides were spiked into sediment samples to determine the effectiveness of the ultrasonic extraction method. The average recoveries of pyrethroids and phenylpyrazoles in sediment at 4 {sup o}C storage on day 0, 1, 7, 14, and 21 ranged from 98.6 to 120.0%, 79.2 to 116.0%, 85.0 to 119.7%, 93.6 to 118.7%, and 92.1 to 118.2%, respectively, with all percent relative standard deviations less than 10% (most < 6%). This illustrated the stability of pyrethroids and phenylpyrazoles in sediment during sediment aging at 4 {sup o}C. Recoveries of the pesticides ranged from 98.6% to 120.0% for lowest fortification level (2-16 {mu}g kg{sup -1}), from 97.8% to 117.9% for middle fortification level (10-80 {mu}g kg{sup -1}), and from 94.3% to 118.1% for highest fortification level (20-160 {mu}g kg{sup -1}). Relative standard deviations of pesticide recoveries were usually less than 7%. Method detection limits of target pesticides ranged from 0.22 {mu}g kg{sup -1} to 3.72 {mu}g kg{sup -1}. Furthermore, field sediment samples collected from four residential lakes during a three-month monitoring period were analyzed to evaluate the effectiveness of this method. Bifenthrin was detected in all of sediment samples (highest concentration 260.33 {+-} 41.71 {mu}g kg{sup -1}, lowest concentration 5.68 {+-} 0.38 {mu}g kg{sup -1}), and fipronil sulfone was detected at least once in sediment samples collected from three sites with concentrations ranging from 1.73 {+-} 0.53 to 7.53 {+-} 0.01 {mu}g kg{sup -1}. - Highlights: {yields} A rapid extraction and copper-based clean-up method was

  16. 超声波流量计在船舶管系泄漏检测与定位中的应用%Application of Ultrasonic Flow Meter in Detecting and Locating Ship Pipeline Leakage

    Institute of Scientific and Technical Information of China (English)

    韩雪峰; 张杰; 彭中波

    2012-01-01

    提出了基于负压波—流量平衡联合法的超声波流量计来检测船舶管系泄漏和泄漏点定位的方法.从超声波流量计的工作原理和应用特点入手,结合压力波在泄漏检测与定位系统中的应用情况,搭建实验平台,进行了实验验证.实验结果表明:该方法具有一定的实用性和可行性,能有效地提高小泄漏的检测率和降低泵阀正常操作的误报警.%Ship pipeline leakage can be detected and located by utilizing ultrasonic flow meter hased on negative pressure waves and flow equilibrium method. An experiment platform was created on lhe basis of the operating prinripJe and application characteristics of ultrasonic flow meter, the utilization of negative pressure waves in ship pipeline leakage and location system. Then the application of ultrasonic was verified, moreover, it showed that small leakage can be more easily detected and the frequency of false alarms during the normal operating of the pump valve can also be effectively decreased if ultrasonic flow meter based on negative pressure waves and flow equilibrium method was utilized in ship pipeline leakage detection and location, thus the practical applicability and feasibility of this method were demonstrated.

  17. Ultrasonic flaw detection and sizing methods for cracks in the nozzle corner area at boiling water reactor vessels

    International Nuclear Information System (INIS)

    The demonstration of inservice inspection methods with ultrasound for the nozzel inner corner at boiling water reactor pressure vessels has shown that a detectability of cracks with a depth in the range of 5-10 mm is possible if optimal inspection parameters are chosen. The investigations concerning the choice of the optimal parameters is presented

  18. Ultrasonic flaw detection and sizing methods for cracks in the nozzle corner area at boiling water reactor vessels

    International Nuclear Information System (INIS)

    The demonstration of inservice inspection methods with ultrasound for the nozzle inner corner at boiling water reactor pressure vessels has shown that a detectability of cracks with a depth in the range of 5 - 10 mm is possible if optimal inspection parameters are chosen. The investigations concerning the choice of the optimal parameters is presented. 4 refs

  19. Distribution of ultrasonic radiofrequency signal amplitude detects lipids in atherosclerotic plaque of coronary arteries: an ex-vivo study

    Directory of Open Access Journals (Sweden)

    Moroi Masao

    2008-05-01

    Full Text Available Abstract Background Accumulation of lipids within coronary plaques is an important process in disease progression. However, gray-scale intravascular ultrasound images cannot detect plaque lipids effectively. Radiofrequency signal analysis could provide more accurate information on preclinical coronary plaques. Methods We analyzed 29 zones of mild atheroma in human coronary arteries acquired at autopsy. Two histologic groups, i.e., plaques with a lipid core (group L and plaques without a lipid core (group N, were analyzed by automatic calculation of integrated backscatter. One hundred regions of interest were set on the target zone. Radiofrequency signals from a 50 MHz transducer were digitized at 240 MHz with 12-bit resolution. The intensity of integrated backscatter and its distribution within each plaque were compared between the two groups. Results Although the mean backscatter was similar between the groups, intraplaque variation of backscatter and backscatter in the axial direction were larger in group L than in group N (p = 0.02. Conventional intravascular ultrasound showed extremely low sensitivity for lipid detection, despite a high specificity. In contrast, a cut-off value>32 for the total variance of integrated backscatter identified lipid-containing plaque with a high sensitivity (85% and specificity (75%. Conclusion Compared with conventional imaging, assessment of the intraplaque distribution of integrated backscatter is more effective for detecting lipid. As coronary atheroma progresses, its composition becomes heterogeneous and multi-layered. This radiofrequency technique can portray complex plaque histology and can detect the early stage of plaque progression.

  20. Ultrasonic Detection of Small Crack in Studs[Bolts] by Time Difference of Thread Signals(TDTS)

    International Nuclear Information System (INIS)

    It is difficult to detect such flaws as stress - corrosion cracking or corrosion wastage(loss of bolt diameter) in the threads. In many cases the critical size of a flaw is very small(1-2 mm order). This paper describes how it is possible to discriminate small flaw indications in threads using the time difference or thread signals(TDTS) by a signal-conditioning technique

  1. Inspection of copper canisters for spent nuclear fuel by means of ultrasonic array system. Modelling, defect detection and grain noise estimation

    International Nuclear Information System (INIS)

    The work presented in the report has been split into three overlapping tasks which have the following objectives: (1) development of beam-forming tools, and verification of modeling tools; (2) investigation of detection and resolution limits; (3) evaluation of attenuation, estimation and suppression of grain noise. For beam-forming tools, a method of designing steered and/or focused beams in immersed solids is presented based on geometrical acoustics. Presently, the beam designs are only related to delays but not to apodization. These focused, steered beams are intended to be used for sizing defects and inspecting the regions close to canisters outer walls. The modeling tool developed previously for simulating elastic fields radiated by planar arrays into immersed solids has been verified by comparing with the results obtained from PASS, a software developed by Dr. Didier Cassereau, France. The results from our modeling tool are in excellent agreement with those from PASS. Since the array coming with the ALLIN ultrasonic array system is not planar, but cylindrically curved in elevation, and it works not in transmission mode, but in pulse echo mode, the above modeling tool for the planar arrays cannot be applied directly. Therefore, the modeling tool has been upgraded for the ALLIN array. The theory underlying this modeling tool is the extended angular spectrum approach (ASA) which was developed based on the conventional ASA that only applies to planar sources. Experimental verification of the modeling tool has shown that the results from the tool agree very well with the measurements. To quantify the fields from the ALLIN array and to facilitate the comparison of simulated results with the measured ones, the ALLIN array system has been calibrated based on the existing functionality, and an analytical model has been proposed for simulating measured acoustic echo pulses. To investigate the detection and resolution limits, we have carried out a series of experiments

  2. Inspection of copper canisters for spent nuclear fuel by means of ultrasonic array system. Modelling, defect detection and grain noise estimation

    Energy Technology Data Exchange (ETDEWEB)

    Wu Ping; Stepinski, T. [Uppsala Univ., (Sweden). Dept. of Material Science

    1998-07-01

    The work presented in the report has been split into three overlapping tasks which have the following objectives: (1) development of beam-forming tools, and verification of modeling tools; (2) investigation of detection and resolution limits; (3) evaluation of attenuation, estimation and suppression of grain noise. For beam-forming tools, a method of designing steered and/or focused beams in immersed solids is presented based on geometrical acoustics. Presently, the beam designs are only related to delays but not to apodization. These focused, steered beams are intended to be used for sizing defects and inspecting the regions close to canisters outer walls. The modeling tool developed previously for simulating elastic fields radiated by planar arrays into immersed solids has been verified by comparing with the results obtained from PASS, a software developed by Dr. Didier Cassereau, France. The results from our modeling tool are in excellent agreement with those from PASS. Since the array coming with the ALLIN ultrasonic array system is not planar, but cylindrically curved in elevation, and it works not in transmission mode, but in pulse echo mode, the above modeling tool for the planar arrays cannot be applied directly. Therefore, the modeling tool has been upgraded for the ALLIN array. The theory underlying this modeling tool is the extended angular spectrum approach (ASA) which was developed based on the conventional ASA that only applies to planar sources. Experimental verification of the modeling tool has shown that the results from the tool agree very well with the measurements. To quantify the fields from the ALLIN array and to facilitate the comparison of simulated results with the measured ones, the ALLIN array system has been calibrated based on the existing functionality, and an analytical model has been proposed for simulating measured acoustic echo pulses. To investigate the detection and resolution limits, we have carried out a series of experiments

  3. Detection of blister formation and evaluation of pressure tube/calandria tube contact location by ultrasonic velocity ratio measurement technique

    International Nuclear Information System (INIS)

    Presence of hydrogen in zircaloy pressure tube affects the velocity of ultrasound propagation. Both longitudinal wave velocity (VL) and shear wave velocity (VS) are affected depending on the concentration of hydrogen. Velocity ratio (VL/VS) changes as per the concentrations of hydrogen in different locations along the length of pressure tube. A hydride blister which forms at the pressure tube and calandria tube contact point is a distinct zone containing hydrogen 2-3 order of magnitude more than the parent matrix and hence, can be detected by sharp change in velocity ratio. (author)

  4. Detection and sizing of stress corrosion cracks in austenitic components using ultrasonic testing and synthetic aperture focusing technique

    Energy Technology Data Exchange (ETDEWEB)

    Dugan, Sandra; Wagner, Sabine [Stuttgart Univ. (Germany). Materialpruefungsanstalt; Dillhoefer, Alexander [NDT Global GmbH and Co.KG, Stutensee (Germany); Rieder, Hans; Spies, Martin [Fraunhofer-Institut fuer Zerstoerungsfreie Pruefverfahren (IZFP), Saarbruecken (Germany)

    2015-05-01

    Flaw detection and sizing using NDT techniques is an important factor for reliably assessing the integrity of components. In the case of dissimilar metal welds and austenitic stainless steel welds, the grain structure of the weld in combination with the elastic anisotropy of the material will present major challenges for UT. A study on austenitic base metal test blocks with artificially grown IGSCCs has shown that the Synthetic Aperture Focusing Technique (SAFT) can improve the signal-to-noise ratio, particularly for crack tip signals. In welded test blocks, the influence of the inhomogeneous, anisotropic weld has to be considered.

  5. Detection and sizing of stress corrosion cracks in austenitic components using ultrasonic testing and synthetic aperture focusing technique

    International Nuclear Information System (INIS)

    Flaw detection and sizing using NDT techniques is an important factor for reliably assessing the integrity of components. In the case of dissimilar metal welds and austenitic stainless steel welds, the grain structure of the weld in combination with the elastic anisotropy of the material will present major challenges for UT. A study on austenitic base metal test blocks with artificially grown IGSCCs has shown that the Synthetic Aperture Focusing Technique (SAFT) can improve the signal-to-noise ratio, particularly for crack tip signals. In welded test blocks, the influence of the inhomogeneous, anisotropic weld has to be considered.

  6. Verification of ultrasonic indications in austenitic overlay

    International Nuclear Information System (INIS)

    An austenitic overlay on steel 15Kh2MFA was tested by an ultrasonic probe. Overlays of this kind are used in nuclear reactor pressure vessels. The results of the ultrasonic method were compared with those of the metallographic method. Metallographic analysis showed that the majority of defects found by ultrasonic tests included clusters of cavities, welded-in slag and cracks, which mostly occurred between the weld beads. The experiments gave evidence that defects not smaller than 0.5 mm in size can be well detected at depths not exceeding 7 mm. (M.D.). 3 figs

  7. Fundamentals of picosecond laser ultrasonics.

    Science.gov (United States)

    Matsuda, Osamu; Larciprete, Maria Cristina; Li Voti, Roberto; Wright, Oliver B

    2015-02-01

    The aim of this article is to provide an introduction to picosecond laser ultrasonics, a means by which gigahertz-terahertz ultrasonic waves can be generated and detected by ultrashort light pulses. This method can be used to characterize materials with nanometer spatial resolution. With reference to key experiments, we first review the theoretical background for normal-incidence optical detection of longitudinal acoustic waves in opaque single-layer isotropic thin films. The theory is extended to handle isotropic multilayer samples, and is again compared to experiment. We then review applications to anisotropic samples, including oblique-incidence optical probing, and treat the generation and detection of shear waves. Solids including metals and semiconductors are mainly discussed, although liquids are briefly mentioned. PMID:24998119

  8. Ultrasonic inspection methodology

    International Nuclear Information System (INIS)

    Steam generator tubes are known to be susceptible to stress corrosion cracking (SCC). Primary water SCC (PWSCC) and more recently secondary water SCC (SWSCC) have been observed in some Belgian plants. To help dealing with these problems, Laborelec developed an ultrasonic (UT) inspection system. It has been used for the last two years on a sampling basis in several plants. The field and laboratory measurements confirmed the advantage of using UT for the early detection of small circumferential cracks while an excellent correlation was demonstrated between eddy current RPC and UT for axial PWSCC. In conclusion: The latest in-service inspections demonstrated an average measurement cycle of 50 to 60 seconds per tube including the manipulator displacement from tube to tube. A sample of about 250 tubes with axial cracks was measured on-site with the eddy current RPC technique and the new UT system. All the UT measured lengths were within ± 1.5 mm of the RPC results. The same results were obtained from the inspection of the tubes repaired with the nickel process (Doel 3). Some indications of circumferential secondary side stress corrosion cracking were recently observed. A comparison with the eddy current rotating pancake coil confirmed the improved detectability of the UT system. The field and laboratory results obtained with this UT inspection system demonstrated the advantage of applying the ultrasonic technique for the detection and sizing of small volume cracks like SCC. Also, the small focal spot of the UT beam provided a clear advantage for the detection of circumferential PWSCC in the presence of multiple axial cracks. With an average rate dose to 60 tubes per hour for the top of the tubesheet area, this UT system can be considered as an industrial tool for the inspection of steam generator tubes

  9. Pre and post garter spring repositioning ultrasonic inspection of pressure tubes

    International Nuclear Information System (INIS)

    This paper present a description of the ultrasonic cracked hydride blister detections system used for pre and post inspection of pressure tubes during garter spring repositioning in CNE (Embalse Nuclear Power Station). Ultrasonic system setup configuration, transducers characteristics, blister detection head, calibration of parameters, operating procedure, records of ultrasonic inspections and evaluation. (author)

  10. Characteristics of artifacts in two kinds of multi detector-row CT. An examination of the angle dependence for a slice plane

    International Nuclear Information System (INIS)

    We examined using the phantom whether there would be the tendency of artifact generated by Multi Detector-row CT (MD-CT) and the angle dependence between artifact and the structure to a slice side. In addition whether it is artifact peculiar to MD-CT with use of Single Detector-row CT. Even if images are obtained by pith-up, to set the thin collimation is one of the methods reduce artifact. When we take clinical usefulness into consideration the images cannot be obtain by sufficient S/N ratio, duration of respiratory suspension and more thin-section. It is necessary to carry out further experiment and examinations obtain images into consideration. (author)

  11. Ultrasonic flowmeter for JSFR

    International Nuclear Information System (INIS)

    The piping materials of the Japan Sodium-Cooled Fast Reactor (JSFR) at the commercialized stage, will be ferromagnetic materials Mod. 9-Cr steel.Therefore, it is not feasible to adopt the electromagnetic flowmeters used in conventional FBR plants. This paper describes the developmental status of the ultrasonic flowmeter system (USFM) as a substitute flow rate measurement system to JSFR. The features of the USFM are the following; In consideration of the double wall piping structure on JSFR, ultrasonic transducers should be installed directly on the surface of the inner primary coolant pipe. Therefore, the transducers should work properly under the temperature of 395 degrees Cat the rated power, and be replaced by remote replacement system; The transducer remote exchange system should maintain with air tightness between the inner primary coolant piping and the outer piping during the normal plant operation, apply appropriate pressure to the transducers against the inner primary coolant piping, and exchange the transducers without removing the outer piping under the maintenance outage; Multi-pass propagation time method is effective for detection of flow rate in the short entrance region (e.g. in the short straight piping) and the requirements of the signal processing equipment are the following; Linearity and repeatability of output signal : less than± 2% of Full Scale; Fluctuation rate of output signal : less than ± 5% of median; Response : less than 0.3 s; The USFM is designed as one of the Safety Protection System

  12. Ultrasonic Flowmeter for JSFR

    International Nuclear Information System (INIS)

    The piping materials of the Japan Sodium-Cooled Fast Reactor (JSFR) at the commercialized stage, will be ferromagnetic materials Mod. 9-Cr steel. Therefore, it is not feasible to adopt the electromagnetic flowmeters used in conventional FBR plants. This paper describes the developmental status of the ultrasonic flowmeter system (USFM) as a substitute flow rate measurement system for JSFR. The features of the USFM are the following; - In consideration of the double wall piping structure of JSFR, ultrasonic transducers should be installed directly on the surface of the inner primary coolant piping. Therefore, the transducers should work properly under 395 oC at the rated power, and be replaced by a remote replacement system. - The transducer remote replacement system should maintain the air tightness between the inner primary coolant piping and the outer piping during the normal plant operation, apply appropriate pressure to the transducers against the inner primary coolant piping, and replace the transducers without removing the outer piping under the maitenance outage. - The multi-pass propagation time method is effective for detection of the flow rate in the short entrance region (in the short straight piping). The requirements of the signal processor are the following; Linearity and repeatability of the output signal : ± 2% or less of full scale; Fluctuation rate of the output signal : ± 5% or less of the median; Response : 0.3 s or less. - The USFM is designed as one of the safety protection system. (author)

  13. 钢管超声波自动探伤控制装置的研制与应用%Development and Application of Ultrasonic Automatic Flaw Detection Control Device for Steel Pipe

    Institute of Scientific and Technical Information of China (English)

    常少文; 杨彤

    2012-01-01

    In this article, it analyzed structure and implement proposal of ultrasonic automatic flaw detection control device, as well as its application in steel pipe inspection. This device utilizes unitization and modular structure design to ensure stable extraction of control signal and echo signal, accuracy and high efficiency of continuous automatic flaw detection. The application results showed that this device possesses some advantages, such as high automation degree, running fast, good compatibility, versatility, and so on. It improved accuracy and reliability of ultrasonic automatic flaw detection, achieved misinformation rate is less than 2%, missing rate is zero, which meets production requirements of ultrasonic automatic detection for steel pipe.%分析了超声波自动探伤控制装置的组成结构、实施方案以及在钢管检测中的应用情况.该超声波自动探伤控制装置采用单元化和模块化结构设计,保证了控制信号、回波信号的稳定提取以及连续自动化探伤检测的准确性和高效率.实际使用结果表明,该装置具有自动化程度高,运行节拍快,兼容性及通用性良好等特点.该装置的使用提高了超声波自动检测的准确性和可靠性,做到了误判率小于2%,漏检率为0,满足了钢管超声波自动检测的生产要求.

  14. Isotope dilution quantification of ultratrace gamma-glutamyl-Se-methylselenocysteine species using HPLC with enhanced ICP-MS detection by ultrasonic nebulisation or carbon-loaded plasma.

    Science.gov (United States)

    Goenaga Infante, Heidi; Ovejero Bendito, María del Carmen; Cámara, Carmen; Evans, Linda; Hearn, Ruth; Moesgaard, Sven

    2008-04-01

    A method for the accurate determination of ultratrace selenium species of relevance to cancer research, such as gamma-glutamyl-Se-methylselenocysteine (gamma-glutamyl-SeMC), using species-specific double isotope dilution analysis (IDA) with HPLC-ICP-MS is reported for the first time. The (77)Se-enriched gamma-glutamyl-SeMC spike was produced in-house by collecting the fraction at the retention time of the gamma-glutamyl-SeMC peak from a chromatographed aqueous extract of (77)Se-enriched yeast, pooling the collected fractions and freeze-drying the homogenate. The Se content of this spike was characterised using reverse isotope dilution mass spectrometry (IDMS) and the isotopic composition of this spike was checked prior to quantification of the natural abundance dipeptide species in garlic using speciated IDA. The extraction of the gamma-glutamyl-SeMC species in water was performed in a sonication bath for 2 h after adding an appropriate quantity of (77)Se-enriched gamma-glutamyl-SeMC to 50 mg of garlic to give optimal (78)Se/(77)Se and (82)Se/(77)Se ratios of 1.5 and 0.6, respectively. The effect of ultrasonic nebulisation, in comparison with the loading of the ICP with carbon (through the addition of methane gas on-line), on the detection of Se associated with gamma-glutamyl-SeMC using collision/reaction cell ICP-MS with hydrogen as collision gas was investigated. Sensitivity enhancements of approximately fourfold and twofold were achieved using USN and methane mixed plasma, respectively, in comparison with conventional nebulisation and conventional Ar ICP-MS. However, an approximately twofold improvement in the detection limit was achieved using both approaches (42 ng kg(-1) for (78)Se using peak height measurements). The use of species-specific IDMS enabled quantification of the dipeptide species at ng g(-1) levels (603 ng g(-1) Se) in the complex food matrix with a relative standard deviation (RSD, n = 4) of 4.5%, which was approximately half that obtained

  15. Detection and Recognition of Aluminums Alloy Stress Corrosion Crack by Ultrasonic Thermal Wave Method%基于超声热波方法的铝合金应力腐蚀裂纹检测与识别

    Institute of Scientific and Technical Information of China (English)

    金国锋; 张炜; 杨正伟; 田干; 黄智勇

    2013-01-01

    针对飞行器结构中应力腐蚀裂纹的快速高效检测需求,采用超声红外热波方法进行了检测试验研究.在改进WOL铝合金材料应力腐蚀裂纹试件上,改变超声激励位置在裂纹尖端延伸方向并沿裂纹接触面的切线方向上、在裂纹尖端延伸方向并垂直于裂纹接触面上以及在试件开口延伸方向并垂直于裂纹接触面上,获得了不同激励位置下试件的表面温度场分布,通过提取裂纹方向上的线温,实现了对裂纹的定量识别.结果表明:超声红外热波技术能够快速准确地检测到铝合金应力腐蚀裂纹,将超声波激励源布置在裂纹尖端延伸方向并垂直于裂纹接触面上时,能够更好地激发裂纹缺陷.%For the needs of fast and efficient detection of stress corrosion crack in aircraft structure, the ultrasonic infrared thermal wave method was applied for the detection research. An improved aluminum alloy WOL stress crack specimen was detected by changing the ultrasonic excitation position respectively at the crack tip extension direction that along the crack surface tangential direction, at the crack tip extension direction and perpendicular to the crack contact surface, and at the crack hatch extension direction and perpendicular to the crack contact surface, obtained the surface temperature distribution of the specimen under different excitation positions. The crack was quantitatively identified by picking-up and anglicizing the line temperature along the crack direction. The results show that; the ultrasonic thermal wave method can quickly and accurately detected aluminum alloy stress corrosion crack, and the crack can be better detected by locating the ultrasonic excitation at the crack tip extension direction and perpendicular to the crack contact surface.

  16. Ultrasonic Microtransport

    Science.gov (United States)

    Moroney, Richard Morgan, III

    We have observed numerous kinetic effects using ultrasonic flexural plate waves (FPWs) in 4mu -thick composite plates of low-stress silicon nitride, piezoelectric zinc oxide and aluminum. The wavelength is typically 100 mum, and the area 3 x 8 mm^2. A successful new surface micromachining fabrication process is presented here for the first time. FPWs have been used to move liquids and gasses with motion typically indicated by polysilicon blocks in air and polystyrene spheres in water; the velocity in air is 4.5 mm/s (with a zero-to-peak input of 3 V), and in water it is 100 mum/s (with an input of 7.8 V). Other observations include pumping of a liquid dye, and mixing near the FPW surface. All quantitative observations demonstrate that the kinetic effects of FPWs are proportional to the square of the wave amplitude. The amplitude for a typical device is 250 A at 9 V input; the power in a typical FPW is about 2 mW. The amplitude can be accurately measured using a laser diffraction technique. Experimental error is about +/-10%, and many of the results agree well with a simple theory to predict the FPW amplitude; extensions of the theory model the fluid loading of FPW devices, but experiment and theory disagree by about 15%. Pumping by flexural plate waves is an example of the phenomenon known as acoustic streaming. A common solution approach is the method of successive approximations, where the nonlinear equations are first linearized and solved. This "first-order" solution is then used to determine the inhomogeneous source terms in the linearized, "second -order" equations of motion. Theoretical predictions of streaming theory are in excellent agreement with experiment in the case where the FPW device contacts a half-space of fluid; predictions for flow in small channels encourage the development of integrated micropumps. Applications for microflow include thermal redistribution in integrated circuits and liquid movement in analytical instruments--particularly where

  17. Measurement of crack length by ultrasonic attenuation coefficient

    International Nuclear Information System (INIS)

    In this paper, the ultrasonic attenuation coefficient was measured by variation of crack length for Double-Cantilever Beam(DCB) specimen. The energy release rate, G, was obtained by the experimental measurement of compliance. The experimental results represents that the crack length for the ultrasonic attenuation coefficient and energy release rate is increases proportionally. From the experimental results, we proposed a detecting method of the crack length by the ultrasonic attenuation coefficient and discussed it

  18. Software Design and Application of Ultrasonic Automatic Flaw Detection System of Welded Steel Pipes%焊接钢管超声波自动探伤系统中的软件设计与应用

    Institute of Scientific and Technical Information of China (English)

    常少文

    2011-01-01

    The software design of pipe ultrasonic automatic flaw detection system, and its application on welded steel pipes production were introduced. It combined traditional ultrasonic inspection technology with some advanced technologies, such as industrial control computer, virtual instrument, intelligent flaw detection, etc. With the careful programming flaw detection operation, it could evaluate correctly and select strictly for complex flaw echo, its error in alarm could be effectively avoided. The review of flaw echo waveform overcame insufficiency of flaw category identification in ultrasonic automatic inspection, and achieved misinformation rate being smaller than 2%, and fail to report rate being zero.%分析了焊接钢管超声波自动探伤系统的软件设计以及在焊接钢管检测中的应用状况.把传统的超声波检测技术和先进的工业控制计算机、虚拟仪器和智能化探伤等技术相结合,配合精心编制的探伤操作程序,可做到对复杂缺陷回波的准确评价和严格筛选,有效地避免了系统的误报警.缺陷波形回放功能克服了超声波自动探伤中的缺陷种类难以识别的不足,并做到误报率<2%,漏报率为0.

  19. Ultrasonic testing of materials at level 2

    International Nuclear Information System (INIS)

    Ultrasonic inspection is a nondestructive method in which high frequency sound waves are introduced into the material being inspected. Ultrasonic testing has a superior penetrating power to radiography and can detect flaws deep in the test specimen (say up to about 6 to 7 meters of steel). It is quite sensitive to small flaws and allows the precise determination of the location and size of the flaws. Basic ultrasonic test methods such as the through transmission method and the resonance method, sensors and testing techniques are described. Pulse echo type flaw detectors and their applications for inspection of welds are surveyed. Ultrasonic standards, calibration of the equipment and evaluation methods are presented. Examples of practical applications in welding, casting and forging processes are given. Figs and tabs

  20. Ultrasonic wave inspection device

    International Nuclear Information System (INIS)

    The device of the present invention inspects incore structural components by visualizing them by scanning an ultrasonic transducer in an opaque liquid metal sodium in a pressure vessel of an FBR type reactor. Namely, a piezoelectric vibrator for transmitting/receiving ultrasonic waves is formed into a protruded shape. A portion at the center of the protruded piezoelectric vibrator is coaxially separated. Upon transmitting ultrasonic waves, a large opening of the entire piezoelectric vibrator is used. A small opening at the center of the piezoelectric vibrator is used upon receiving ultrasonic waves. With such a constitution, an object to be inspected is visualized based on the waveform of the received ultrasonic wave signals defining the center of a curvature of the protruded piezoelectric vibrator as a position of transmitting ultrasonic waves and defining the center of the opening at the center of the piezoelectric vibrator as a position of receiving ultrasonic waves. As a result, the energy of the ultrasonic waves can be enhanced to improve sensitivity upon transmitting ultrasonic waves. Since the distance between an optional position of the receiving surface and the reflecting surface of the object is minimized upon receiving ultrasonic waves, there is no distortion in the waveforms of the received signals thereby enabling to obtain images at high accuracy. (I.S.)

  1. Computer Simulation of Multiple Reflection Waves for Thickness Measurement by Ultrasonic Spectroscopy

    International Nuclear Information System (INIS)

    Ultrasonic spectroscopy is likely to become a very powerful NDE method for detection of microfects and thickness measurement of thin film below the limit of ultrasonic distance resolution in the opaque materials, provides a useful information that cannot be obtained by a conventional ultrasonic measuring system. In this paper, we considered a thin film below the limit of ultrasonic distance resolution sandwitched between two substances as acoustical analysis model, demonstrated the usefulness of ultrasonic spectroscopic analysis technique using information of ultrasonic frequency for measurements of thin film thickness, regardless of interference phenomenon and phase reversion of ultrasonic waveform. By using frequency intervals(Δf) of periodic minima from the ratio of reference power spectrum of reflective waveform obtained a sample to power spectrum of multiple reflective waves obtained interference phenomenon caused by ultrasonic waves reflected at the upper and lower surfaces of a thin layer, can measured even dimensions of interest are smaller than the ultrasonic wave length with simplicity and accuracy

  2. Ultrasonic/Sonic Impacting Penetrators

    Science.gov (United States)

    Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Stark, Randall A.

    2008-01-01

    Ultrasonic/sonic impacting penetrators (USIPs) are recent additions to the series of apparatuses based on ultrasonic/sonic drill corers (USDCs). A USIP enables a rod probe to penetrate packed soil or another substance of similar consistency, without need to apply a large axial force that could result in buckling of the probe or in damage to some buried objects. USIPs were conceived for use in probing and analyzing soil to depths of tens of centimeters in the vicinity of buried barrels containing toxic waste, without causing rupture of the barrels. USIPs could also be used for other purposes, including, for example, searching for pipes, barrels, or other hard objects buried in soil; and detecting land mines. USDCs and other apparatuses based on USDCs have been described in numerous previous NASA Tech Briefs articles. The ones reported previously were designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. To recapitulate: A USDC can be characterized as a lightweight, low-power, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. As shown in the figure, a basic USDC includes a piezoelectric stack, a backing and a horn connected to the stack, a free mass (free in the sense that it can slide axially a short distance between the horn and the shoulder of tool bit), and a tool bit, i.e., probe for USIP. The piezoelectric stack is driven at the resonance frequency of the stack/horn/backing assembly to create ultrasonic vibrations that are mechanically amplified by the horn. To prevent fracture during operation, the piezoelectric stack is held in compression by a bolt. The bouncing of the free mass between the horn and the tool bit at sonic frequencies generates hammering actions to the bit that are more effective for drilling than is the microhammering action of ultrasonic vibrations in ordinary ultrasonic drills. The hammering actions

  3. Hand Gesture Recognition Using Ultrasonic Waves

    KAUST Repository

    AlSharif, Mohammed Hussain

    2016-04-01

    Gesturing is a natural way of communication between people and is used in our everyday conversations. Hand gesture recognition systems are used in many applications in a wide variety of fields, such as mobile phone applications, smart TVs, video gaming, etc. With the advances in human-computer interaction technology, gesture recognition is becoming an active research area. There are two types of devices to detect gestures; contact based devices and contactless devices. Using ultrasonic waves for determining gestures is one of the ways that is employed in contactless devices. Hand gesture recognition utilizing ultrasonic waves will be the focus of this thesis work. This thesis presents a new method for detecting and classifying a predefined set of hand gestures using a single ultrasonic transmitter and a single ultrasonic receiver. This method uses a linear frequency modulated ultrasonic signal. The ultrasonic signal is designed to meet the project requirements such as the update rate, the range of detection, etc. Also, it needs to overcome hardware limitations such as the limited output power, transmitter, and receiver bandwidth, etc. The method can be adapted to other hardware setups. Gestures are identified based on two main features; range estimation of the moving hand and received signal strength (RSS). These two factors are estimated using two simple methods; channel impulse response (CIR) and cross correlation (CC) of the reflected ultrasonic signal from the gesturing hand. A customized simple hardware setup was used to classify a set of hand gestures with high accuracy. The detection and classification were done using methods of low computational cost. This makes the proposed method to have a great potential for the implementation in many devices including laptops and mobile phones. The predefined set of gestures can be used for many control applications.

  4. 钢管超声波自动探伤横向扫查系统的改造%Reform to Steel Pipe Automatic Ultrasonic Flaw Detection Transverse Scanning

    Institute of Scientific and Technical Information of China (English)

    汪超; 张兴权; 刘胜斌

    2014-01-01

    通过分析某钢管公司目前钢管超声波自动探伤设备的配置和钢管在扩径后发现的缺陷类型,找出了钢管扩径后超声波自动检测时偶尔发现焊缝横向缺陷的原因,提出了对现有钢管超声波自动探伤横向扫查系统的改造措施,即改变了横向探头及探头架的布置,增加了检测监视的通道数量。改造后的检测系统可靠性高,操作简便,稳定性好,探伤人员容易掌握。通过对该自动探伤横向扫查的改造,降低了钢管缺陷漏检的风险,提高了生产效率。%Through analysis on the configuration of steel pipe automatic ultrasonic flaw detection and defects type after pipe expansion in some steel pipe company,it got the reason of weld transverse defects occasionally found out during automatic ultrasonic inspection after pipe expansion,and put forward the reform measures of the existing automatic ultrasonic inspection transverse scanning. That is varying the arrangement of transverse probes and probe frame,adding monitor channel quantity. After reform,the testing system is with high reliability,simple operation,good stability,and the inspection personnel easy to master. The reforms decrease the risk of steel pipe missing detection,and enhance the productivity.

  5. Strong spin-orbit coupling and Zeeman spin splitting in angle dependent magnetoresistance of Bi{sub 2}Te{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Rik, E-mail: rikdey@utexas.edu; Pramanik, Tanmoy; Roy, Anupam; Rai, Amritesh; Guchhait, Samaresh; Sonde, Sushant; Movva, Hema C. P.; Register, Leonard F.; Banerjee, Sanjay K. [Microelectronics Research Center, University of Texas at Austin, Austin, Texas 78758 (United States); Colombo, Luigi [Texas Instruments, Dallas, Texas 75243 (United States)

    2014-06-02

    We have studied angle dependent magnetoresistance of Bi{sub 2}Te{sub 3} thin film with field up to 9 T over 2–20 K temperatures. The perpendicular field magnetoresistance has been explained by the Hikami-Larkin-Nagaoka theory alone in a system with strong spin-orbit coupling, from which we have estimated the mean free path, the phase coherence length, and the spin-orbit relaxation time. We have obtained the out-of-plane spin-orbit relaxation time to be small and the in-plane spin-orbit relaxation time to be comparable to the momentum relaxation time. The estimation of these charge and spin transport parameters are useful for spintronics applications. For parallel field magnetoresistance, we have confirmed the presence of Zeeman effect which is otherwise suppressed in perpendicular field magnetoresistance due to strong spin-orbit coupling. The parallel field data have been explained using both the contributions from the Maekawa-Fukuyama localization theory for non-interacting electrons and Lee-Ramakrishnan theory of electron-electron interactions. The estimated Zeeman g-factor and the strength of Coulomb screening parameter agree well with the theory. Finally, the anisotropy in magnetoresistance with respect to angle has been described by the Hikami-Larkin-Nagaoka theory. This anisotropy can be used in anisotropic magnetic sensor applications.

  6. Assessment of scan-angle dependent radiometric bias of Suomi-NPP VIIRS day/night band from night light point source observations

    Science.gov (United States)

    Bai, Yan; Cao, Changyong; Shao, Xi

    2015-09-01

    The low gain stage of VIIRS Day/Night Band (DNB) on Suomi-NPP is calibrated using onboard solar diffuser. The calibration is then transferred to the high gain stage of DNB based on the gain ratio determined from data collected along solar terminator region. The calibration transfer causes increase of uncertainties and affects the accuracy of the low light radiances observed by DNB at night. Since there are 32 aggregation zones from nadir to the edge of the scan and each zone has its own calibration, the calibration versus scan angle of DNB needs to be independently assessed. This study presents preliminary analysis of the scan-angle dependence of the light intensity from bridge lights, oil platforms, power plants, and flares observed by VIIRS DNB since 2014. Effects of atmospheric path length associated with scan angle are analyzed. In addition, other effects such as light changes at the time of observation are also discussed. The methodology developed will be especially useful for JPSS J1 VIIRS due to the nonlinearity effects at high scan angles, and the modification of geolocation software code for different aggregation modes. It is known that J1 VIIRS DNB has large nonlinearity across aggregation zones, and requires new aggregation modes, as well as more comprehensive validation.

  7. Structural Coloration Pigments based on Carbon Modified ZnS@SiO2 Nanospheres with Low-Angle Dependence, High Color Saturation, and Enhanced Stability.

    Science.gov (United States)

    Wang, Fen; Zhang, Xin; Lin, Ying; Wang, Lei; Zhu, Jianfeng

    2016-02-24

    Vividly structurally colored pigments produced by employing materials with high indices of refraction such as ZnS, TiO2, or ZrO2 have attracted great attention recently. Generally, pigments with high refractive index based on three-dimensional ordered macroporous (3DOM) structures were prepared by a colloidal crystal template method. However, the preparation of 3DOM structures is time-consuming. Moreover, it will also lead to iridescent colors. In this work, structurally colored pigments based on carbon-modified core-shell nanospheres of ZnS@SiO2 were prepared by a homogeneous deposition method, followed by a modified Stöber method and a calcination process. Compared with conventional method, the pigments prepared in our work shows high color saturation, enhanced stability and low angle dependent. Typical paints composed of pigments and ethanol could be spray coated on any substrates without limitation. These core-shell structural coloration pigments have potential applications for displays, colorimetric sensors, and pigments. PMID:26824514

  8. Wedges for ultrasonic inspection

    Energy Technology Data Exchange (ETDEWEB)

    Gavin, Donald A. (Rexford, NY)

    1982-01-01

    An ultrasonic transducer device is provided which is used in ultrasonic inspection of the material surrounding a threaded hole and which comprises a wedge of plastic or the like including a curved threaded surface adapted to be screwed into the threaded hole and a generally planar surface on which a conventional ultrasonic transducer is mounted. The plastic wedge can be rotated within the threaded hole to inspect for flaws in the material surrounding the threaded hole.

  9. An application of ultrasonic phased array imaging in electron beam welding inspection

    Institute of Scientific and Technical Information of China (English)

    周琦; 刘方军; 李志军; 李旭东; 齐铂金

    2002-01-01

    The basic principle and features of ultrasonic phased array imaging are discussed in this paper. Through the ultrasonic phased array technology, the electron beam welding defects and frozen keyholes characterization and imaging were realized. The ultrasonic phased array technology can detect kinds of defects in electron beam welding (EBW) quickly and easily.

  10. On-site materials testing using digital ultrasonic test instruments

    International Nuclear Information System (INIS)

    Ultrasonic instruments have a wide range of applications in nondestructive materials testing, e.g. in wall or sheet thickness measurements, in measurements of the anisotropy or the external stresses of materials, and especially in detecting flaws, e.g. pores, bubbles, slag inclusions, etc. Details of an ultrasonic measuring instrument are presented. (orig./HP)

  11. Advance ultrasonic instrumentation and sensor for tubing industries

    International Nuclear Information System (INIS)

    For thin wall tubing specially in nuclear industry, there are number of institutes/industries provides dimension and flaw detection ultrasonic units. However, full dimension information, for example average ID, OD, wall thickness, true ID, OD, wall thickness, ovality and eccentricity etc. is not available. The paper discusses the state-of-the-art Ultrasonic System and Sensor and its application in tubing industries

  12. Standard practice for leaks using ultrasonics

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 Practice A, Pressurization—This practice covers procedures for calibration of ultrasonic instruments, location, and estimated measurements of gas leakage to atmosphere by the airborne ultrasonic technique. 1.2 In general practice this should be limited to leaks detected by two classifications of instruments, Class I and Class II. Class I instruments should have a minimum detectable leak rate of 6.7 × 10−7 mol/s (1.5 × 10−2 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Class II instruments should have a minimal detectable leak rate of 6.7 × 10−6 mol/s (1.5 × 10−1 std. cm3/s at 0°C) or more for the pressure method of gas leakage to atmosphere. Refer to Guide E432 for additional information. 1.3 Practice B, Ultrasonic Transmitter—For object under test not capable of being pressurized but capable of having ultrasonic tone placed/injected into the test area to act as an ultrasonic leak trace source. 1.3.1 This practice is limited to leaks producing leaka...

  13. Ultrasonic inspection of inpile tubes

    International Nuclear Information System (INIS)

    The in-service inspection (ISI) of inpile tubes can be performed accurately and safely with a semiautomatic ultrasonic inspection system. The ultrasonic technique uses a set of multiple transducers to detect and size cracks, voids, and laminations radially and circumferentially. Welds are also inspected for defects. The system is designed to inspect stainless steel and Inconel tubes ranging from 53.8 mm (2.12 in.) to 101.6 mm (4 in.) inner diameter with wall thickness on the order of 5 mm. The inspection head contains seven transducers mounted in a surface-following device. Six angle-beam transducers generate shear waves in the tubes. Two of the six are oriented to detect circumferential cracks, and two detect axial cracks. Although each of these four transducers is used in the pulse-echo mode, they are oriented in aligned sets so pitch-catch operation is possible if desired. The remaining angle-beam transducers are angulated to detect flaws that are off axial or circumferential orientation. The seventh transducer is used for longitudinal inspection and detects and sizes laminar-type defects

  14. Nondestructive evaluation of a cermet coating using ultrasonic and eddy current techniques

    International Nuclear Information System (INIS)

    This paper describes a series of experiments conducted to characterize cermet coatings using conventional ultrasonic and eddy current techniques as well as an ultrasonic leaky surface wave method. The results demonstrate the ability of these techniques to detect the presence of artificial defects on the surface or beneath the surface of the coating. In addition, ultrasonic tests in particular ultrasonic leaky surface waves demonstrate the ability to detect the presence of manufacturing flaws. Ultrasonic time-of-flight and eddy current quadrature measurements also show sensitivity to variations in coating thickness

  15. Proceedings of the specialists' meeting on reliability of the ultrasonic inspection of austenitic materials

    International Nuclear Information System (INIS)

    The contributions of this meeting addressed several topics: the fundamentals of ultrasonic examination of austenitic materials (effect of anisotropy on propagation, improvement of ultrasonic testing to thick bimetallic welds, aspects of the ultrasonic testing of austenitic steel structures, utilization of a Fisher linear discriminant function in intergranular stress corrosion cracking or IGSCC detection, case of coarse grain austenitic welds, efforts of the Argonne National Laboratory), instruments and methods (longitudinal wave ultrasonic inspection, Grass echo suppression technique during the ultrasonic inspection of fuel cladding tubes, inspections of fillet and butt welds, improvement by signal averaging techniques, multiple bearing angle crack detector for cladded pipes examinations, flow-to-grain echo enhancement by split-spectrum processing, ultrasonic imaging techniques, ultrasonic inspection of pipe weldments for IGSCC), industrial practice (ultrasonic testing techniques for fabrication and in-service inspection, experiences in ultrasonic examination of austenitic steel components, experience and practice on nuclear piping in Spain, detection of underclad defects, sizing of cracks perpendicular to stainless overlay), and reliability (survey of ultrasonic testing in austenitic weld material, examination of electron beam welds, factors affecting the reliability of ultrasonic examination, detectability of IGSCC, ultrasonic inspection reliability for primary piping systems)

  16. Towards monomaterial p-n junctions: Single-step fabrication of tin oxide films and their non-destructive characterisation by angle-dependent X-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    The application of a non-destructive method for characterization of electronic structure of an ultra-thin SnO1angle dependent XPS, we quantified stoichiometry changes inside the SnO1detected upward energy levels shift in the substrate's electronic structure, these results suggest a negative charge displacement across the SiO2 layer. As a consequence, there is a significant carrier concentration gradient in the layer, from a nearly insulating oxide at the SnOx surface to a semiconducting one at the bottom of the SnOx film. The results showed that the application of a simple and cost-effective method allows tuning the materials' properties towards the one-step fabrication of materials with ambipolar doping

  17. Towards monomaterial p-n junctions: Single-step fabrication of tin oxide films and their non-destructive characterisation by angle-dependent X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Krzywiecki, Maciej, E-mail: Maciej.Krzywiecki@polsl.pl [Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany); Institute of Physics–CSE, Silesian University of Technology, Konarskiego 22B, 44-100 Gliwice (Poland); Sarfraz, Adnan; Erbe, Andreas [Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Str. 1, 40237 Düsseldorf (Germany)

    2015-12-07

    The application of a non-destructive method for characterization of electronic structure of an ultra-thin SnO{sub 1angle dependent XPS, we quantified stoichiometry changes inside the SnO{sub 1detected upward energy levels shift in the substrate's electronic structure, these results suggest a negative charge displacement across the SiO{sub 2} layer. As a consequence, there is a significant carrier concentration gradient in the layer, from a nearly insulating oxide at the SnO{sub x} surface to a semiconducting one at the bottom of the SnO{sub x} film. The results showed that the application of a simple and cost-effective method allows tuning the materials' properties towards the one-step fabrication of materials with ambipolar doping.

  18. Ultrasonic non invasive techniques for microbiological instrumentation

    Science.gov (United States)

    Elvira, L.; Sierra, C.; Galán, B.; Resa, P.

    2010-01-01

    Non invasive techniques based on ultrasounds have advantageous features to study, characterize and monitor microbiological and enzymatic reactions. These processes may change the sound speed, viscosity or particle distribution size of the medium where they take place, which makes possible their analysis using ultrasonic techniques. In this work, two different systems for the analysis of microbiological liquid media based on ultrasounds are presented. In first place, an industrial application based on an ultrasonic monitoring technique for microbiological growth detection in milk is shown. Such a system may improve the quality control strategies in food production factories, being able to decrease the time required to detect possible contaminations in packed products. Secondly, a study about the growing of the Escherichia coli DH5 α in different conditions is presented. It is shown that the use of ultrasonic non invasive characterization techniques in combination with other conventional measurements like optical density provides complementary information about the metabolism of these bacteria.

  19. 大直径直缝双面埋弧焊管超声波检测质量控制%Ultrasonic Detection Quality Control for Large Diameter Longitudinal Weld Double-side Submerged arc Welded Pipe

    Institute of Scientific and Technical Information of China (English)

    汪超; 王成; 刘胜斌; 金博; 范锋

    2015-01-01

    Aiming at technology requirements of relevant welded pipe standards used for petroleum and gas pipeline project, in this article, it respectively provided probe display, sensitivity setting and specific detection methods of all kinds of defects in ultrasonic detection of steel plate and welded pipe. The type characteristics of various defects existing in the steel and welded pipe type were analyzed;the special probes used in ultrasonic detection were designed. It also introduced acceptance standard and application method. The usage of dedicated probes and special probes increased online detection efficiency, reduced material wastage, and ensured welded pipe quality.%针对天然气管道工程用焊管相关标准的技术要求,分别给出了钢板和焊管超声波检测时的探头布置、灵敏度设置及各类缺陷的具体检测方法。分析了钢板或焊管中存在的各种缺陷的类型特征,设计了超声波检测时所用的专用探头和特殊探头。介绍了焊管生产过程中超声波检测的验收标准和特殊探头的使用方法。应用结果表明,专用探头和特殊探头的使用,提高了焊管在线检测效率,降低了材料损耗,确保了焊管产品质量。

  20. Effect of decision making on ultrasonic examination performance

    International Nuclear Information System (INIS)

    A decision aid was developed to overcome examiner limitations in information processing and decision making during ultrasonic examinations. The aid provided a means of noting signal characteristics as they were observed during the examination, and of presenting them simultaneously for decision making. The aid also served as a way of providing detailed feedback on examination performance during training. The aid was incorporated into worksheets used for the conduct of practice examinations during ultrasonic examination training. To support the introduction and use of the decision aid, one hour of supplementary training was inserted in an existing 64-hour training course on ultrasonic detection of defects. This study represented a modest step in improving the performance of ultrasonic examinations in nuclear power plants. Findings indicated that aided decision making supported by limited training can significantly improve ultrasonic detection performance

  1. Ultrasonic assisted-ECAP.

    Science.gov (United States)

    Djavanroodi, F; Ahmadian, H; Koohkan, K; Naseri, R

    2013-08-01

    Equal channel angular pressing (ECAP) is one of the most prominent procedures for achieving ultra-fine grain (UFG) structures among the various severe plastic deformation (SPD) techniques. In this study, the effect of ultrasonic vibration on deformation behavior of commercial pure aluminum in the ECAP process is analyzed successfully using three dimensional (3D) by finite element methods (FEMs). The investigation includes the effects of die geometry, billet length, friction factor, ram speed, ultrasonic amplitude and ultrasonic frequency. Conventional as well as ultrasonic ECAP has been performed on aluminium 1070 alloy and the obtained data were used for validating simulations. It is observed that a 13% reduction in the average force was achieved when ultrasonic vibration with amplitude of 2.5 μm at 20 kHz is applied. Also, further reduction in ECAP forming forces are obtained with increase of vibration amplitude, vibration frequency, friction factor, billet length and die channel angle. PMID:23523093

  2. Ultrasonic decontamination robot

    International Nuclear Information System (INIS)

    An ultrasonic decontamination robot removes radioactive contamination from the internal surface of the inlet and outlet headers, divider plate, tube sheet, and lower portions of tubes of a nuclear power plant steam generator. A programmable microprocessor controller guides the movement of a robotic arm mounted in the header manway. An ultrasonic transducer having a solvent delivery subsystem through which ultrasonic action is achieved is moved by the arm over the surfaces. A solvent recovery suction tube is positioned within the header to remove solvent therefrom while avoiding interference with the main robotic arm. The solvent composition, temperature, pressure, viscosity, and purity are controlled to optimize the ultrasonic scrubbing action. The ultrasonic transducer is controlled at a power density, frequency, and on-off mode cycle such as to optimize scrubbing action within the range of transducer-to-surface distance and solvent layer thickness selected for the particular conditions encountered. Both solvent and transducer control actions are optimized by the programmable microprocessor. (author)

  3. A remote and autonomous continuous monitoring ultrasonic system for flood detection in sub-sea members of offshore steel oil rigs

    Energy Technology Data Exchange (ETDEWEB)

    Mijarez-Castro, Rito

    2006-07-01

    This thesis presents a novel and autonomous continuous monitoring system for flood detection in the hollow sub-sea members of offshore steel oil rigs. The technique offers an alternative to underwater nondestructive testing methods based on ultrasound and x-rays, which have been used to detect the presence of seawater in these applications, often with divers or remote operating vehicles. The research consists of theoretical and experimental work necessary for the development of an integral system that can be used in new fixed offshore oil rig designs. The system employs a single piezoelectric transducer which can be permanently attached to the inner wall of every sub-sea structure and which is powered by a normally inert seawater battery. Upon activation, the sensor transmits ultrasonic chirp or tone encoded pulses in the range of 21 k Hz to 42 k Hz, to a monitoring system at deck level for decoding and identifying flooded members. Two approaches to the system were considered during the investigation, depending on the communication channel exploited. These were based on either using the seawater as a propagation medium or using the steel structure as a wave-guide. A system based on theoretical models was built and field experiments were conducted using a purpose built jointed steel pipe structure, 7 m in length, 0.5 m in diameter and 16 mm in thickness. This structure was flooded by complete immersion in seawater. Results obtained using water as communication medium and a frequency in the order of 38 k Hz yielded an attenuation figure of 0.4 d B m{sub -}1 over 100 m, since losses were predominantly geometric. In contrast, using the tubular structure as a wave-guide and axis symmetric guided waves as the excitation, a gross attenuation figure of 1.3 d B m{sub -}1 was attained. In the straight parts of the structure, the attenuation ranged from 0.3 d B m{sub -} 1 to 0.6 d B m{sub -}1. The modes most likely to have been excited within the structure were L(0,5) - L(0

  4. Estimation of Postmortem Interval by Detecting Thickness of Cornea Using Ultrasonic Method%超声法测量角膜厚度推断死亡时间

    Institute of Scientific and Technical Information of China (English)

    吕国丽; 姜富学; 许心舒; 蒋拥军; 李志刚; 王欣; 石河; 余礼聪; 许传超

    2012-01-01

    目的 用超声法测量角膜厚度,探索其死后变化规律.方法 11只家兔随机分为两组,分别为角膜上皮完整组及去角膜上皮组.后者采用机械刮除法去除角膜上皮.利用超声测厚仪连续监测两组动物的死后多个时间点的角膜厚度,并对角膜厚度变化与死亡时间进行相关回归分析.结果 超声法测量角膜上皮完整组死后兔角膜厚度的变化值与死亡时间呈非线性相关,且具有较强的相关性,相关系数为0.922,而去角膜上皮组的相关系数为0.822.结论 超声法测量角膜厚度对推断早期死亡时间具有较可靠的应用前景.完整的角膜上皮对于超声测量角膜厚度具有关键作用.%Objective To explore the postmortem changes of cornea thickness measured by ultrasonic pachymetry. Methods Eleven rabbits were randomly divided into two groups: one group with intact corneal epithelium and another group without intact corneal epithelium. In the later group, the corneal epithelium of the rabbit was scraped using mechanical elimination method. The corneal thickness was monitored continuously by ultrasonic pachymetry at several postmortem interval points in rabbits of the two groups. The changes of corneal thickness and postmortem interval were explored by relative regression analysis. Results The thickness of the cornea showed a strong non-linear correlation with the postmortem interval in the group with intact corneal epithelium. The group with intact corneal epithelium showed the correlation coefficient 0.922 and the group without intact corneal epithelium showed the correlation coefficient 0.822, respectively. Conclusion The corneal thickness measured by ultrasonic pachymetry shows a potential value for estimating early postmortem interval. The intact corneal epithelium is a crucial factor for the measurement of cornea thickness by ultrasonic pachymetry.

  5. Nonlinear Ultrasonic Testing on a Laboratory Concrete Bridge Deck

    Science.gov (United States)

    Roe, Shannon E.; Woodward, C.; Cramer, M. J.

    2007-03-01

    Nonlinear ultrasonic testing has been shown to be extremely sensitive to distributed damage in concrete. Nonlinear nondestructive ultrasonic tests were performed on a laboratory bridge to detect distributed damage in the deck after it had been overloaded. The NLUT detected damage throughout the deck, and of particular interest in locations where damage was not visible. These results were compared to results obtained using pulse velocity tests at the same locations. The nonlinear ultrasonics were several orders of magnitude more sensitive than results obtained from pulse velocity.

  6. Ultrasonic liquid level detector

    Science.gov (United States)

    Kotz, Dennis M.; Hinz, William R.

    2010-09-28

    An ultrasonic liquid level detector for use within a shielded container, the detector being tubular in shape with a chamber at its lower end into which liquid from in the container may enter and exit, the chamber having an ultrasonic transmitter and receiver in its top wall and a reflector plate or target as its bottom wall whereby when liquid fills the chamber a complete medium is then present through which an ultrasonic wave may be transmitted and reflected from the target thus signaling that the liquid is at chamber level.

  7. Ultrasonic washing of textiles.

    Science.gov (United States)

    Choi, Junhee; Kim, Tae-Hong; Kim, Ho-Young; Kim, Wonjung

    2016-03-01

    We present the results of experimental investigation of ultrasonic washing of textiles. The results demonstrate that cavitation bubbles oscillating in acoustic fields are capable of removing soils from textiles. Since the washing performance is mitigated in a large washing bath when using an ultrasonic transducer, we propose a novel washing scheme by combining the ultrasonic vibration with a conventional washing method utilizing kinetic energy of textiles. It is shown that the hybrid washing scheme achieves a markedly enhanced performance up to 15% in comparison with the conventional washing machine. This work can contribute to developing a novel laundry machine with reduced washing time and waste water. PMID:26215790

  8. Ultrasonic synthetic aperture imaging of defects

    International Nuclear Information System (INIS)

    Current reactor systems have been generally designed with limited facility for in-service inspection. Where ultrasonic crack detection and sizing techniques have been applied they appear to be functioning adequately. The purpose of this paper is to introduce a modification to conventional ultrasonic defect sizing which yields acoustic measurements of the dimensions of the defect in its plane parallel to the inspection surface. The technique retains the simplicity of a single probe to collect data, but achieves the effect of multidepth focussing by a particular signal processing procedure. The subject is discussed under the headings: ultrasonic focussing procedures; the basic principle of linear synthetic aperture focussing; the mechanics of the system; the capability of the system; comments and conclusion. (U.K.)

  9. Cognitive correlates of ultrasonic inspection performance

    International Nuclear Information System (INIS)

    This study provided a detailed examination of the thought processes required for conducting successful ultrasonic inspections of nuclear power plant components. When employed to detect or estimate the size of defects in components such as pipes and nozzles, an ultrasonic inspection can be a demanding cognitive task. A successful result requires the mental manipulation of a substantial amount of relevant information: knowledge about the component inspected, understanding of available ultrasonic techniques, and interpretation of an almost infinite variety of signal-characteristics obtained during the inspection. Reaching a correct conclusion from an inspection is a function of both the validity of the information obtained and the effectiveness with which the information is interpreted and weighed. Previous efforts to improve ultrasonic inspection performance have been directed mainly to the improvement of techniques and training for obtaining information. This study addressed improvement of the cognitive processes -- the mental manipulations required to reach a correct conclusion. The study was designed to learn what inspectors were doing and thinking while applying ultrasonic inspection techniques, and to relate key cognitive elements to inspection performance -- that is, to determine what aspects of these cognitive processes discriminate between effective and ineffective inspections. To this end, tape-recorded commentary was obtained and analyzed from 235 inspections of pipe-weld specimens. 26 refs., 39 figs

  10. Ultrasonic testing X gammagraphy

    International Nuclear Information System (INIS)

    The experience of 10 years for substituting gammagraphy tests by ultrasonic tests is related. A comparative evaluation of data obtained from both techniques applied to welded butt joints is presented. (author)

  11. Fundamentals of Medical Ultrasonics

    CERN Document Server

    Postema, Michiel

    2011-01-01

    This book sets out the physical and engineering principles of acoustics and ultrasound as used for medical applications. It covers the basics of linear acoustics, wave propagation, non-linear acoustics, acoustic properties of tissue, transducer components, and ultrasonic imaging modes, as well as the most common diagnostic and therapeutic applications. It offers students and professionals in medical physics and engineering a detailed overview of the technical aspects of medical ultrasonic imaging, whilst serving as a reference for clinical and research staff.

  12. Assessing ultrasonic examination results

    International Nuclear Information System (INIS)

    Amongst nondestructive examination methods, the ultrasonic examination plays an important role. The reason why its scope of application is so wide is because the sound conducting capacity is the only property the material of a test specimen has to have. As the fields are so manifold, only main aspects can be described briefly. The list of references, however, is very extensive and gives plenty of information of all the problems concerning the assessment of ultrasonic examination results. (orig./RW)

  13. Ultrasonic Nondestructive Characterization of Porous Materials

    Science.gov (United States)

    Yang, Ningli

    2011-12-01

    Wave propagation in porous media is studied in a wide range of technological applications. In the manufacturing industry, determining porosity of materials in the manufacturing process is required for strict quality control. In the oil industry, acoustic signals and seismic surveys are used broadly to determine the physical properties of the reservoir rock which is a porous media filled with oil or gas. In porous noise control materials, a precise prediction of sound absorption with frequency and evaluation of tortuosity are necessary. Ultrasonic nondestructive methods are a very important tool for characterization of porous materials. The dissertation deals with two types of porous media: materials with relatively low and closed porosity and materials with comparatively high and open porosity. Numerical modeling, Finite Element simulations and experimental characterization are all discussed in this dissertation. First, ultrasonic scattering is used to determine the porosity in porous media with closed pores. In order get a relationship between the porosity in porous materials and ultrasonic scattering independently and to increase the sensitivity to obtain scattering information, ultrasonic imaging methods are applied and acoustic waves are focused by an acoustic lens. To verify the technique, engineered porous acrylic plates with varying porosity are measured by ultrasonic scanning and ultrasonic array sensors. Secondly, a laser based ultrasonic technique is explored for predicting the mechanical integrity and durability of cementitious materials. The technique used involves the measurement of the phase velocity of fast and slow longitudinal waves in water saturated cement paste. The slow wave velocity is related to the specimen's tortuosity. The fast wave speed is dependent on the elastic properties of porous solid. Experimental results detailing the generation and detection of fast and slow wave waves in freshly prepared and aged water-saturated cement samples

  14. Ultrasonic Nondestructive Characterization of Adhesive Bonds

    Science.gov (United States)

    Qu, Jianmin

    1999-01-01

    Adhesives and adhesive joints are widely used in various industrial applications to reduce weight and costs, and to increase reliability. For example, advances in aerospace technology have been made possible, in part, through the use of lightweight materials and weight-saving structural designs. Joints, in particular, have been and continue to be areas in which weight can be trimmed from an airframe through the use of novel attachment techniques. In order to save weight over traditional riveted designs, to avoid the introduction of stress concentrations associated with rivet holes, and to take full advantage of advanced composite materials, engineers and designers have been specifying an ever-increasing number of adhesively bonded joints for use on airframes. Nondestructive characterization for quality control and remaining life prediction has been a key enabling technology for the effective use of adhesive joints. Conventional linear ultrasonic techniques generally can only detect flaws (delamination, cracks, voids, etc) in the joint assembly. However, more important to structural reliability is the bond strength. Although strength, in principle, cannot be measured nondestructively, a slight change in material nonlinearity may indicate the onset of failure. Furthermore, microstructural variations due to aging or under-curing may also cause changes in the third order elastic constants, which are related to the ultrasonic nonlinear parameter of the polymer adhesive. It is therefore reasonable to anticipate a correlation between changes in the ultrasonic nonlinear acoustic parameter and the remaining bond strength. It has been observed that higher harmonics of the fundamental frequency are generated when an ultrasonic wave passes through a nonlinear material. It seems that such nonlinearity can be effectively used to characterize bond strength. Several theories have been developed to model this nonlinear effect. Based on a microscopic description of the nonlinear

  15. The Development and Modelling of a Novel Clamp-on Ultrasonic-Thermal and Ultrasonic Multiple Reflection Flowmeter for Liquid Applications.

    OpenAIRE

    Law, Masa

    1994-01-01

    The development of a novel combined "ultrasonic/thermal" with "ultrasonic multiple reflections" clamp-on meter for measuring a wide flowrate range of clean liquids in small diameter pipes is presented. Current existing flowmeters based on ultrasound cannot measure very low flowrates for single phase liquids. The ultrasonic/thermal technique can measure single phase flows in the range 0 to 0.6 m s' in pipes with diameters as small as 15 mm. It can also detect and measure reverse...

  16. Ultrasonic Inspection Of Thick Sections

    Science.gov (United States)

    Friant, C. L.; Djordjevic, B. B.; O'Keefe, C. V.; Ferrell, W.; Klutz, T.

    1993-01-01

    Ultrasonics used to inspect large, relatively thick vessels for hidden defects. Report based on experiments in through-the-thickness transmission of ultrasonic waves in both steel and filament-wound composite cases of solid-fuel rocket motors.

  17. Cracks assessment using ultrasonic technology

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Maria Pia; Tomasella, Marcelo [OLDELVAL S.A. Oleoductos del Valle, Rio Negro (Argentina). Pipeline Integrity Dept.

    2005-07-01

    The goal of Oldelval Integrity Program is to prevent ruptures and leaks, developing strategies for a better handling of the integrity of our pipelines. In order to achieve it we have studied and modeled each process that involved in the integrity pipeline. Those processes are mainly based on defects reported by an internal inspection tool and supplied with field inspection and monitoring data. Years of evaluation, study and the continuous effort overturned towards a phenomenon that worries to the industry, as it is the SCC. Since 1998 up to 2004 SCC was included in the integrity program with some preventive maintenance programs. The accomplishment of the inspection based on ultrasound tools, is the culmination of years of evaluation and investigations supported by field digs and materials susceptibility. This paper describes Oldelval's results with ultrasonic crack detection tool, and how it can be reliably to detect SCC. (author)

  18. Ultrasonic diagnosis of neuroinfections in newborns and infants

    International Nuclear Information System (INIS)

    The authors discuss the potentialities of the ultrasonic method in the diagnosis of brain involment in the newborns and infants with neuroinfections. Ultrasonic examination was carried out in 75 infants aged 4 days to 15 months. Fifteen infants suffered from specific neuroinfections that developed in utero the rest 60 developed inflammatory diseases of the central nervous system. Specific changes in the brain morphology were detected at the early stages of inflammatory processes of various origins. Ultrasonic examinations help identify the type of the pathologic process, its dissemination and complications

  19. Ultrasonic testing of austenitic stainless steel welds

    International Nuclear Information System (INIS)

    Ultrasonic testing of austenitic stainless steel welds has been considered difficult because of the high noise level and remarkable attenuation of ultrasonic waves. To improve flaw detectability in this kind of steel, various inspection techniques have been studied. A series of tests indicated: (1) The longitudinal angle beam transducers newly developed during this study can detect 4.8 mm dia. side drilled holes in dissimilar metal welds (refraction angle: 550 from SUS side, 450 from CS side) and in cast stainless steel welds (refraction angle: 450, inspection frequency: 1 MHz). (2) Cracks more than 5% t in depth in the heat affected zones of fine-grain stainless steel pipe welds can be detected by the 450 shear wave angle beam method (inspection frequency: 2 MHz). (3) The pattern recognition method using frequency analysis technology was presumed useful for discriminating crack signals from spurious echoes. (author)

  20. Practical considerations in ultrasonic wall thickness measurement

    International Nuclear Information System (INIS)

    Ultrasonic inspection is widely used by industry for the detection of corrosion and the measurement of material wall thickness. Due to wall thinning and the various forms of corrosion that can be found in pressure piping and pressure vessels the annual cost of corrosion damage and related service failures, is very expensive. The author interest is primarily in the examination of personnel who need to become competent and certificated in the various skills that are required to carry out wall thickness measurement and detection of wall thinning due to corrosion. The various techniques and equipment available for ultrasonic wall thickness measurement and assessment give rise to problems regarding the accuracy of results and detection of corrosion. This paper will discuss some of the corrosion conditions that may occur and also problems that may arise during wall thickness measurement. Methods of improving the wall thickness measurement and the assessment process will also be discussed. (author)

  1. Ultrasonics in Dentistry

    Science.gov (United States)

    Walmsley, A. D.

    Ultrasonic instruments have been used in dentistry since the 1950's. Initially they were used to cut teeth but very quickly they became established as an ultrasonic scaler which was used to remove deposits from the hard tissues of the tooth. This enabled the soft tissues around the tooth to return to health. The ultrasonic vibrations are generated in a thin metal probe and it is the working tip that is the active component of the instrument. Scanning laser vibrometry has shown that there is much variability in their movement which is related to the shape and cross sectional shape of the probe. The working instrument will also generate cavitation and microstreaming in the associated cooling water. This can be mapped out along the length of the instrument indicating which are the active areas. Ultrasonics has also found use for cleaning often inaccessible or different surfaces including root canal treatment and dental titanium implants. The use of ultrasonics to cut bone during different surgical techniques shows considerable promise. More research is indicated to determine how to maximize the efficiency of such instruments so that they are more clinically effective.

  2. The Numerical Simulation Research for the Bend Tube Defects Detection Based on Ultrasonic Guided Wave%基于超声导波检测的弯管缺陷数值模拟研究

    Institute of Scientific and Technical Information of China (English)

    赵冬梅; 罗月迎; 贾传伟; 巫帅珍

    2015-01-01

    For the problem of bend tube defects detection , did some numerical simulation research for the bend tube defects detection based on ultrasonic guided wave testing by using finite element method .First of all, this paper built a 90 degrees bend model , and set double defects like different sizes and different distances in the bend model .Secondly , set the parameters of finite element calculation based on the ultra-sonic guided wave theory .Then, according to the calculation results , made a fitting curve of the influence of corrosion pit defect dimensional change in straight pipe to crack curve reflection coefficient in elbow , and the variation tendency curve of the reflection coefficient with the change of the distances between de -fects is made as well .The results show that when the size of the elbow defects remains constant , the re-flection coefficient decreases with the straight pipe flaw size increasing , and the changing relationship be-tween the reflection coefficient and the distance of the two defects can be ignored .These results have an application value for the bend tube degree of defects detection .%针对弯管缺陷检测的问题,利用有限元方法,对弯管缺陷超声导波检测进行数值模拟. 通过建立90°弯管模型,在弯管中设置不同尺寸以及不同距离的双缺陷,根据超声导波理论设置有限元计算的参数,由计算结果拟合出双缺陷中直管段腐蚀坑缺陷尺寸变化对弯头处裂纹缺陷反射系数的影响曲线以及缺陷间距离不同时反射系数的变化趋势曲线. 结果表明,当弯头处缺陷的尺寸不变时,其反射系数随直管段缺陷尺寸的变大而减小,两个缺陷间的反射系数与两缺陷间的距离变化关系可忽略不计. 研究结果对弯管缺陷程度检测有一定应用价值.

  3. Artificial Intelligence Assists Ultrasonic Inspection

    Science.gov (United States)

    Schaefer, Lloyd A.; Willenberg, James D.

    1992-01-01

    Subtle indications of flaws extracted from ultrasonic waveforms. Ultrasonic-inspection system uses artificial intelligence to help in identification of hidden flaws in electron-beam-welded castings. System involves application of flaw-classification logic to analysis of ultrasonic waveforms.

  4. Ultrasonic colour Doppler imaging

    DEFF Research Database (Denmark)

    Evans, David H; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2011-01-01

    Ultrasonic colour Doppler is an imaging technique that combines anatomical information derived using ultrasonic pulse-echo techniques with velocity information derived using ultrasonic Doppler techniques to generate colour-coded maps of tissue velocity superimposed on grey-scale images of tissue...... weaknesses, perhaps the greatest being that in conventional systems, the velocities measured and thus displayed are the components of the flow velocity directly towards or away from the transducer, while ideally the method would give information about the magnitude and direction of the three-dimensional flow...... vectors. This review briefly introduces the principles behind colour Doppler imaging and describes some clinical applications. It then describes the basic components of conventional colour Doppler systems and the methods used to derive velocity information from the ultrasound signal. Next, a number of new...

  5. Ultrasonic wave propagation in concentrated emulsions and encapsulated emulsions

    OpenAIRE

    Chen, Yinghui

    2007-01-01

    Ultrasonic spectrometry has potential for monitoring chemical processes on line; an important application is the detection of the suspended particle size distribution (PSD) in emulsions. Measured ultrasonic wave attenuation as a function of frequency is compared to the predictions of an adaptive wave propagation model to obtain an estimate of the PSD. Current models are based either on scattering physics, heat transfer, or hydrodynamics, or on a combination of these. Most models give good pre...

  6. Stress Evaluation and Model Validation Using Laser Ultrasonics

    Energy Technology Data Exchange (ETDEWEB)

    Dike, Jay J.; Lu, Wei-yang; Peng, Lawrence W.; Wang, James C. F.

    1999-02-01

    Rayleigh surface waves can be used to evaluate surface stresses and through-thickness stress gradients based on acoustoelasticity. Laser based ultrasonic techniques, which generate and detect surface waves, have the advantages of good spatial resolution and remote operation. The techniques have many potential applications. This is the final report of a LDRD project that is the first to exploit the benefits of laser ultrasonics for stress and stress gradient evaluation.

  7. Ultrasonic Measurement and Characterization of Liquid-Particle Flow

    OpenAIRE

    Wrobel, Barbara Maria

    2012-01-01

    This Ph.D. dissertation consists of primary and complementary studies. The primary studies comprise development of ultrasonic methodology for on-line ultrasonic measurement of liquid-particle flow, in terms simultaneous determination of average particle concentration and flow speed. Developed methodology is also useful for liquid-particle flow characterization, like detection of flow turbulence intensity, particle clustering, appearance of air bubbles as a third phase and for s...

  8. High performances simulation of ultrasonic fields for non destructive testing

    International Nuclear Information System (INIS)

    Ultrasonic imaging is a commonly used method to detect and identify defects in a mechanical part in nuclear applications. For instance a common nuclear application is the inspection of steel pipes and nozzles. Nowadays massively parallel architectures enable the simulation of ultrasonic field emitted by a phased array transducer inspecting a part across a coupling medium. In this paper, regular field computation model will be discussed along its implementations on General Purpose Processors (GPP) and Graphic Processing Units (GPU). (authors)

  9. 基于超声相控阵的轮辋探伤实证分析%Empirical analysis of the rim flaw detection based on ultrasonic phased array

    Institute of Scientific and Technical Information of China (English)

    杨洋; 王泽勇; 李金龙; 高晓蓉

    2012-01-01

    基于相控阵超声探伤技术,采用直射声束法对轮辋轴向缺陷试块中横孔的径向深度和轴向深度进行了检测,精确定位了横孔的位置,并通过AVG曲线法对缺陷的尺寸进行了定量评定和分析.实验结果表明,缺陷较浅则检测的误差波动较小、干扰波较少;缺陷较深则可能出现轮廓回波等非缺陷波,对缺陷回波的分析有较大影响;远场区的缺陷可以通过AVG曲线进行精确评定.%In this paper, direct sound beam method was used to detect the radial and axial depth of the transverse hole in the rim based on the ultrasonic flaw detection technology. The transverse hole was precisely orientated and the defect size was quantitatively evaluated by AVG curve. As the experiment showed, if the defect was shallow, the error fluctuation and interference wave were less. If the defect was deeper, non-defect wave like profile echo would appear, which would affect the analysis of the defect echo. Defects in far-field region could be accurately assessed through the AVG curve.

  10. Application of On-line Detection and Ultrasonic Thickness Measurement%在线监测与超声波测厚技术综合应用分析

    Institute of Scientific and Technical Information of China (English)

    刘忠友; 杨本立

    2011-01-01

    As the crude oil is becoming increasingly poor, the corrosion in the process units of refineries becomes increasingly severe. Several years'testing and practice of application of on-line corrosion detection and ultrasonic thickness measurement in the corrosion detection and protection of refinery process units has proven that the combination of the two techniques can effectively locate the potential hazard and ensure the safe and reliable operation of the units.%随着原油性质的日益劣化,炼油装置的防腐蚀形势越来越严峻。经过几年的摸索和实验,利用腐蚀在线监测与超声波测厚技术相结合的方法,对炼油装置的腐蚀情况进行监测和防护,可互相取长补短,并能有效排查装置安全隐患,保证装置安全平稳运行。

  11. Ultrasonic Characterization of Aerospace Composites

    Science.gov (United States)

    Leckey, Cara; Johnston, Patrick; Haldren, Harold; Perey, Daniel

    2015-01-01

    Composite materials have seen an increased use in aerospace in recent years and it is expected that this trend will continue due to the benefits of reduced weight, increased strength, and other factors. Ongoing work at NASA involves the investigation of the large-scale use of composites for spacecraft structures (SLS components, Orion Composite Crew Module, etc). NASA is also involved in work to enable the use of composites in advanced aircraft structures through the Advanced Composites Project (ACP). In both areas (space and aeronautics) there is a need for new nondestructive evaluation and materials characterization techniques that are appropriate for characterizing composite materials. This paper will present an overview of NASA's needs for characterizing aerospace composites, including a description of planned and ongoing work under ACP for the detection of composite defects such as fiber waviness, reduced bond strength, delamination damage, and microcracking. The research approaches include investigation of angle array, guided wave, and phase sensitive ultrasonic methods. The use of ultrasonic simulation tools for optimizing and developing methods will also be discussed.

  12. Ultrasonic Processing of Materials

    Energy Technology Data Exchange (ETDEWEB)

    Meek, Thomas T.; Han, Qingyou; Jian, Xiaogang; Xu, Hanbing

    2005-06-30

    The purpose of this project was to determine the impact of a new breakthrough technology, ultrasonic processing, on various industries, including steel, aluminum, metal casting, and forging. The specific goals of the project were to evaluate core principles and establish quantitative bases for the ultrasonc processing of materials, and to demonstrate key applications in the areas of grain refinement of alloys during solidification and degassing of alloy melts. This study focussed on two classes of materials - aluminum alloys and steels - and demonstrated the application of ultrasonic processing during ingot casting.

  13. Investigation of an integrated fiber laser sensor system in ultrasonic structural health monitoring

    Science.gov (United States)

    Wu, Qi; Okabe, Yoji

    2016-03-01

    Various optical fiber sensors have been utilized in structural health monitoring (SHM) to detect strain, temperature, and the ultrasonic guided wave, which is the main measurand discussed in this study. By leveraging existing ultrasonic optical fiber sensors based on fiber Bragg grating (FBG) technique, we proposed a novel sensing concept in which the ultrasonic-induced Bragg wavelength shift was demodulated by an erbium fiber laser (EFL). The ultrasonic sensor and light source, i.e., an FBG and EFL, were seamlessly integrated into a fiber laser sensor system, in which the output power change directly represents the ultrasonic signal. In addition to discussing the theory behind the sensor, we focused on the applications and actual performance of the sensor, including sensitivity, bandwidth, and robustness, in practical ultrasonic SHM. We were able to constantly detect ultrasonic signals in the range of 25 °C-85 °C or simultaneously detect static measurands (temperature or strain) and ultrasonic signals by changing the position of the FBG where it is attached. Because of the diverse structures of the EFL and FBG, we created, investigated, and compared three sensing systems with different properties and advantages to find their most suitable applications and fully explore their maximum potential. In addition, the experimental results from these novel optical fiber sensors were compared to those from a conventional broadband PZT sensor. The results showed that the new sensor has some unique advantages, such as self-adjustable ultrasonic detection.

  14. Ultrasonic testing of reactive powder concrete.

    Science.gov (United States)

    Washer, Glenn; Fuchs, Paul; Graybeal, Benjamin A; Hartmann, Joseph Lawrence

    2004-02-01

    Concrete is a critical material for the construction of infrastructure facilities throughout the world. Traditional concretes consist of cement paste and aggregates ranging in size from 6 to 25 mm that form a heterogeneous material with substantial compressive strength and a very low tensile strength. Steel reinforcement is used to provide tensile strength for reinforced concrete structures and as a composite the material is useful for structural applications. A new material known as reactive powder concrete (RPC) is becoming available. It differs significantly from traditional concrete; RPC has no large aggregates, and contains small steel fibers that provide additional strength and, in some cases, can replace traditional steel reinforcement. Due to its high density and lack of aggregates, ultrasonic inspections at frequencies 10 to 20 times that of traditional concrete inspections are possible. This paper reports on the initial findings of research conducted to determine the applicability of ultrasonic testing techniques for the condition assessment of RPC. Pulse velocities for shear and longitudinal waves and ultrasonic measurement of the modulus of elasticity for RPC are reported. Ultrasonic crack detection for RPC also is investigated. PMID:15055809

  15. Ultrasonic sectional imaging for crack identification. Part 1. Confirmation test of essential factors for ultrasonic imaging

    International Nuclear Information System (INIS)

    Since the first reports of inter-granular stress corrosion crack (IGSCC) in boiling water reactor (BWR) pipe in the 1970s, nuclear power industry has focused considerable attention on service induced crack detection and sizing using ultrasonic examination. In recent years, phased array systems, those reconstruct high quality flaw images at real time are getting to apply for crack detection and sizing. But because the price of phased array systems are expensive for inspection vendors, field application of phased array systems are limited and reliable ultrasonic imaging systems with reasonable price are expected. This paper will discuss cost effective ultrasonic equipment with sectional image (B-scan) presentation as the simplified imaging system for assisting ultrasonic examination personnel. To develop the simplified B-scan imaging system, the frequency characteristics of IGSCC echoes and neighboring geometry echoes such as base-metal to weld interface and inner surface of a pipe are studied. The experimental study confirmed the reflectors have different frequency characteristics and 2MHz is suitable to visualize IGSCC and 5MHz and higher frequency are suitable to reconstruct geometry images. The other study is the amplifier selection for the imaging system. To reconstruct images of IGSCC and geometry echoes, the ultrasonic imaging instrument with linear amplifier has to adjust gain setting to the target. On the other hand, the ultrasonic imaging instrument with logarithmic amplifier can collect and display wider dynamic range on a screen and this wider dynamic range are effective to visualize IGSCC and geometry echoes on a B-scan presentation at a time. (author)

  16. Inline high frequency ultrasonic particle sizer

    Science.gov (United States)

    Lefebvre, F.; Petit, J.; Nassar, G.; Debreyne, P.; Delaplace, G.; Nongaillard, B.

    2013-07-01

    This paper reports the development of a new method of particle sizing in a liquid. This method uses high frequency focused ultrasounds to detect particles crossing the focal zone of an ultrasonic sensor and to determine their size distribution by processing the reflected echoes. The major advantage of this technique compared to optical sizing methods is its ability to measure the size of particles suspended in an opaque liquid without any dedicated sample preparation. Validations of ultrasonic measurements were achieved on suspensions of polymethyl methacrylate beads in a size range extending from a few micrometer to several hundred micrometer with a temporal resolution of 1 s. The inline detection of aggregate formation was also demonstrated.

  17. Design of Ultrasonic Detection System of Engineering Truck Loading Capacity Based on STC12C5A60S2 Microcontroller%基于超声波的STC12C5A60S2单片机的工程车装载量检测系统设计

    Institute of Scientific and Technical Information of China (English)

    冼子翔; 华斌

    2013-01-01

    Based on an effective non-contact ultrasonic distance measurement principle, uses STC12-C5A60S2 microcontroller controls ultrasonic module to launch ultrasonic beams, can not only get real-time detection of changes in truck loading, but also exclude the case of artificial shel-ter to make intelligent judgments on no-load and full load. The system uses ultrasonic modules to work in turn, the mode which ensures the system stability and reliability.%基于超声波有效的非接触式的测距原理,STC12C5A60S2单片机通过控制超声波模块发射超声波波束去实时检测工程车装载量的变化,并且能排除人为遮挡的情况下对工程车空载或者满载做出智能判断。该系统采用超声模块轮循的工作方式保证系统的稳定性和可靠性。

  18. Experiments with Ultrasonic Transducers.

    Science.gov (United States)

    Greenslade, Thomas R., Jr.

    1994-01-01

    Discusses the use of 40 kHz ultrasonic transducers to study wave phenomena. Determines that the resulting wavelength of 9 mm allows acoustic experiments to be performed on a tabletop. Includes transducer characteristics and activities on speed of sound, reflection, double- and single-slit diffraction, standing waves, acoustical zone plate, and…

  19. Ultrasonic Drilling and Coring

    Science.gov (United States)

    Bar-Cohen, Yoseph

    1998-01-01

    A novel drilling and coring device, driven by a combination, of sonic and ultrasonic vibration, was developed. The device is applicable to soft and hard objects using low axial load and potentially operational under extreme conditions. The device has numerous potential planetary applications. Significant potential for commercialization in construction, demining, drilling and medical technologies.

  20. Ultrasonic-test-equipment for rotation tubes

    International Nuclear Information System (INIS)

    The paper describes specifications and the configuration of a ultrasonic equipment for the testing of spinning tubes. Specifications: - Flaw detection inside and outside (resolution of 5μm), Wa-1 thickness measurement (accuracy +- 1,5μ), inner diameter measurement (accuracy +- 20μ), On-Line data processing, equipment completely automatic controlled. The results concerning measurement accuracy, reproducibility and stability during test conditions are presented. (orig.)

  1. Ultrasonic examination of cast stainless steel

    International Nuclear Information System (INIS)

    We present the recent results of a program between CEA and EDF concerning ultrasonic examination of cast stainless steel. We compare the results obtained with different transducers, in particular large aperture composite transducers. We present different signal processing techniques (Spit Spectrum Processing) and image processing, developed to increase signal to noise ratio. Detection capabilities for artificial defects in different structures (equiaxed, columnar structures) are discussed. (authors). 2 refs., 15 figs

  2. The technique of detecting the laser-ultrasonic vector displacement with a confocal Fabry-Perot interferometer waves in a plate

    Institute of Scientific and Technical Information of China (English)

    PAN Yongdong; QIAN Menglu

    2003-01-01

    Generally, a confocal Fabry-Perot interferometer is only able to detect the out-of-plane component of a displacement field; while the in-plane component often has the information about the material which cannot be found in this out-of-plane component. In this paper, based on a confocal Fabry-Perot interferometer set-up for detecting the out-of-plane component of a laser generated acoustic field, a technique is developed to detect both the out-of-plane and inplane displacement components simultaneously with a novel two-channel confocal Fabry-Perot interferometer.

  3. Development status of ultrasonic test techniques for cast stainless steel

    International Nuclear Information System (INIS)

    Ultrasonic testing has been thought to be difficult to apply to cast stainless steel which is used as the material for the main coolant pipes in pressurized water reactors (PWRs). An ultrasonic testing technique using large aperture twin crystal transducers was developed in INSS for application to inspection of the main coolant pipes. The method was evaluated in an application to detect circumferential and axial defects in the cast stainless steel pipes. It was found that (1) the defects could be detected which had a depth that was so small that their evaluation was not required; and (2) depth sizing and length sizing of detected defects were also possible. (author)

  4. Precise measurement of ultrasonic parameters using labVIEW

    International Nuclear Information System (INIS)

    There are many ultrasonic measurement methods that are used in nondestructive testing applications. Some typical applications include material property determination, microstructural characterization, and flaw detection. Ultrasonic parameters such as velocity and attenuation are most commonly required in these applications. The accuracy and repeatability of testing results are dependent on both the hardware used to propagate and receive the ultrasonic waveforms and on the analysis software for calculating these parameters. In this study, five analysis algorithms were implemented on a computer for measuring wave speed in a pulse echo, immersion testing configuration. A commercial software package LabVIEW was used. In velocity measurements comparisons were made between the overlap, cross-correlation, Fourier spectroscopy, phase slope, Hilbert transform algorithms. Attenuation was also measured using the Fourier spectroscopy method. Each algorithm has been applied to a steel sample and produced ultrasonic velocity within 1 percent of the mean for all five algorithms.

  5. Azimuthal-angle dependence of charged-pion-interferometry measurements with respect to 2$^{\\rm nd}$- and $3^{\\rm rd}$-order event planes in Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV

    OpenAIRE

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y; Al-Bataineh, H.; Alexander, J.; Aoki, K.; Aramaki, Y.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.

    2014-01-01

    Charged-pion-interferometry measurements were made with respect to the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event plane for Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV. A strong azimuthal-angle dependence of the extracted Gaussian-source radii was observed with respect to both the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event planes. The results for the 2$^{\\rm nd}$-order dependence indicate that the initial eccentricity is reduced during the medium evolution, but not reversed in the final ...

  6. Research on reducing electromagnetic disturbance of laboratory-made ultrasonic detection devices%减小自制超声检测仪器电磁干扰研究

    Institute of Scientific and Technical Information of China (English)

    罗强龙; 韩庆邦; 王俊; 单鸣雷; 朱昌平

    2013-01-01

    为了尽量降低电磁干扰引起的测量误差,在分析了不同性质电磁干扰的基础上,以超声混凝土内裂纹检测实验为例,论述了立足实验室条件降低电磁干扰的一般方法.实验结果表明,综合采用这些方法能够有效降低电磁干扰,增强实验结果的可重复性.%Laboratory-made electronic devices are not possible to make an overall planning and design for electromagnetic shielding as well as the mature developed electronic products which are strictly based on industry standards. Therefore, it makes that the electromagnetic disturbance could affect the accuracy of experimental results. In order to minimize experimental data errors caused by electromagnetic disturbance, after analyzing different types of electromagnetic disturbances, this article designs a general method of reducing electromagnetic disturbance under laboratory conditions. The ultrasonic crack detection is used in concrete as an example. Then, experimental result shows that this approach could effectively reduce low-frequency electromagnetic disturbance, and enhance a strong repeatability of the experimental results.

  7. Flaw Determination and Evaluation of Ultrasonic Automatic Flaw Detection System for Welded Steel Pipes%焊接钢管超声波自动探伤中的缺陷相关评判方法

    Institute of Scientific and Technical Information of China (English)

    常少文; 吕育栋; 曹华勇; 田岩平; 刘常庆; 韩玉朝; 孙志敏

    2012-01-01

    分析了焊接钢管超声波自动探伤检测中的缺陷相关评判方法,配合编制的时间相关、位置相关、行为相关、特征相关、性质相关的5种相关法判伤软件程序,使自动化探伤系统具有了智能评判功能,可做到对复杂缺陷回波的准确评价和严格筛选,有效地避免了系统的误报警,可满足连续自动化探伤要求,并做到误报率〈2%,漏报率为0。%The flaw determination and evalution methods of ultrasonic automatic flaw detection examining on welded steel pipes are introduced. With the careful programming of time correlation, location correlation, behavior correlation, features correlation, and nature correlation together with related software program, the testing system thus has a smart judgment function to evaluate correctly and select strictly for complex flaw echo, and its error in alarm can be effectively avoided. So designed system was able to meet the continuous automation testing requirements and achieve misinformation rate smaller 2% and fail to report rate to 0.

  8. Proceedings of the specialists' meeting on acoustic/ultrasonic detection of in sodium water leaks on steam generators, held in Aix-en-Provence, France, 1-3 October 1990

    International Nuclear Information System (INIS)

    23 officially nominated persons and 8 observers from 7 countries operating fast breeder reactors in the world, Mr. Arkhipov, IAEA Scientific Secretary of IWGFR and Mr. Cambillard, French member of IWGFR attended the specialists meeting. 25 papers were presented in the national status session and in 3 technical sessions devoted to methods, theoretical approach and real steam generator experience. A separate abstract was prepared for each of these papers. Since the last meetings in Dimitrovgrad and Petten it is clear that acoustic/ultrasonic monitoring of in-sodium water leaks is now considered by all countries as a major topic for commercial fast reactor steam generator unit protection. At this time the detection of leakage events is thought to be possible in the leak range from 1 to about 100 g/s in a time period of a few seconds to a few tens of seconds. Future work should aim at a more precise definition of the attainable limits, taking into account the particular requirements of actual plant design. Refs, figs and tabs

  9. Detection of Signals of Mock-up Pipes of Carbon Steel and Stainless Steel using Guided Ultrasonic Waves due to Magnetostrictive Sensors

    International Nuclear Information System (INIS)

    A piping mock-up with a diameter of 6 inch and schedule number 80 of carbon steel and stainless steel were fabricated. The signals of weldments of these pipes were detected with a torsional vibration mode of frequency of 32 kHz using sensors, such as a pure Ni or a 49Fe-49Co-2V alloy strip. The signals from the 49Fe-49Co-2V alloy strip sensor were more detectable than those from the Ni strip sensor. The signals of 49Fe-49Co-2V alloy strip sensor of tile stainless steel piping mock-up were more detectable than those of 49Fe-49Co-2V alloy strip sensor of the carbon steel piping mock-up.

  10. Cheese maturity assessment using ultrasonics.

    Science.gov (United States)

    Benedito, J; Carcel, J; Clemente, G; Mulet, A

    2000-02-01

    The relationship between Mahon cheese maturity and ultrasonic velocity was examined. Moisture and textural properties were used as maturity indicators. The ultrasonic velocity of the cheese varied between 1630 and 1740 m/s, increasing with the curing time mainly because of loss of water, which also produced an increase of the textural properties. Because of the nature of low-intensity ultrasonics, velocity was better related to those textural parameters that involved small displacements. Ultrasonic velocity decreased with increasing temperature because of the negative temperature coefficient of the ultrasonic velocity of fat and the melting of fat. These results highlight the potential use of ultrasonic velocity measurements to rapidly and nondestructively assess cheese maturity. PMID:10714857

  11. Ultrasonic NDE Classifications with the Gradient Descent Method and Synthetic Aperture Focusing Technique

    International Nuclear Information System (INIS)

    Ultrasonic inspection methods are widely used for detecting flaws in materials. One of the more popular methods involves the extraction of an appropriate set of features followed by the use of a neural network for the classification of the signals in the feature space. This paper describes an approach which uses LMS method to determine the coordinates of the ultrasonic probe followed by the use of SAFT to estimate the location of the ultrasonic reflector. The method is employed for classifying NDE signals from the steam generator tubes in a nuclear power plant. The classification results using this scheme for the ultrasonic signals from cracks and deposits within steam generator tubes are presented

  12. Ultrasonic thermometer isolation standoffs

    International Nuclear Information System (INIS)

    A method is provided for minimizing sticking of the transmission line to the protective sheath and preventing noise echoes from interfering with signal echoes in an improved high temperature ultrasonic thermometer which includes an ultrasonic transmission line surrounded by a protective sheath. Small isolation standoffs are mounted on the transmission line to minimize points of contact between the transmission line and the protective sheath, the isolation standoffs serving as discontinuities mounted on the transmission line at locations where a signal echo is desired or where an echo can be tolerated. Consequently any noise echo generated by the sticking of the standoff to the protective sheath only adds to the amplitude of the echo generated at the standoff and does not interfere with the other signal echoes. 6 claims, 3 figures

  13. Inspection system for welded tubular joint based on ultrasonic phased array

    Institute of Scientific and Technical Information of China (English)

    Hao Guangping; Deng Zongquan; Shan Baohua; Yu Weizhen; Li Lifang

    2010-01-01

    A manual inspection of large-diameter tubular joints is difficult. As a result a scanner with three degrees of freedom (DOFs) was developed based on the scanning principle of ultrasonic phased array. The weld tracing is realized by a 2D0F motion of scanner. The pose of ultrasonic probe is controlled by the third one. The control strategy is put forward based on a programmable multi-axis controller. Four kinds of scanning modes can be implemented simultaneously employing this ultrasonic inspection system. Experiments on reference blocks of tubular joints reveal that the automatic ultrasonic phased array inspection system has the same inspection accuracy as a manual ultrasonic inspection. This system is superior to the manual ultrasonic system in terms of reliability and repeatability. The artificial defects of weld at tubular joint can be detected accurately with the presented inspection system.

  14. Reliability Assessment of Ultrasonic Nondestructive Inspection Data Using Monte Carlo Simulation

    Science.gov (United States)

    Park, Ik-Keun; Kim, Hyun-Mook

    2003-03-01

    Ultrasonic NDE is one of important technologies in the life-time maintenance of nuclear power plant. Ultrasonic inspection system is consisted of the operator, equipment and procedure. The reliability of ultrasonic inspection system is affected by its ability. The performance demonstration round robin was conducted to quantify the capability of ultrasonic inspection for in-service. The small number of teams who employed procedures that met or exceeded ASME Sec. XI Code requirements detected the piping of nuclear power plant with various cracks to evaluate the capability of detection and sizing. In this paper, the statistical reliability assessment of ultrasonic nondestructive inspection data using Monte Carlo simulation is presented. The results of the probability of detection (POD) analysis using Monte Carlo simulation are compared to these of logistic probability model. In these results, Monte Carlo simulation was found to be very useful to the reliability assessment for the small NDE hit/miss data sets.

  15. Ultrasonic nondestructive tubing inspection system

    International Nuclear Information System (INIS)

    A system for measuring the extent of tube wall erosion in an inspection region of a heat exchanger tube of a nuclear steam generator, uses an ultrasonic means driven helically inside the eroded tube which may be filled with a fluid (e.g., water) to minimize ultrasonic wave attenuation. A control means cooperates with the ultrasonic means to produce a map of the tube wall thickness in an inspection region

  16. [Development of ultrasonic power meter].

    Science.gov (United States)

    Huang, Hongxin; Hu, Changming; Zheng, Yan; Xu, Honglei; Zhou, Wohua; Wu, Ziwen; Yu, Liudan; Hao, Jiandong; Luo, Yifan

    2014-07-01

    This article describes the design and development of an ultrasonic power meter which is consist of an electronic balance, a practice target, an acoustic enclosures and a blocking. The electronic balance mounted on the blocking is linked with the practice target by connecting rod. By adjusting the blocking makes the practice target suspended above ultrasound probe, and then the ultrasonic power can be measured. After initial tests, the ultrasonic power meter performanced with good stability and high precision. PMID:25330604

  17. Pulsed ultrasonic stir welding system

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2013-01-01

    An ultrasonic stir welding system includes a welding head assembly having a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. During a welding operation, ultrasonic pulses are applied to the rod as it rotates about its longitudinal axis. The ultrasonic pulses are applied in such a way that they propagate parallel to the longitudinal axis of the rod.

  18. Intravascular Ultrasonic Imaging

    OpenAIRE

    Tobis, JM; Mahon, D.; Moriuchi, M; Mallery, JA; Lehmann, K; Griffith, J.; Gessert, J; Zalesky, P; McRae, M; Dwyer, ML; Henry, WL

    1990-01-01

    Because conventional imaging methods are inadequate for evaluating human coronary arteries in vivo, an intravascular ultrasonic imaging catheter was developed that allows the arterial wall to be studied in cross-section from within the artery. The catheter incorporates a mechanically rotating 20-MHz transducer, which is designed so that the ringdown occurs within the catheter and imaging is permitted up to the catheter's surface. The device rotates at 1800-rpm within a plastic sleeve and prov...

  19. Acoustic emission monitoring and ultrasonic examination correlation on a reactor pressure vessel. Final report

    International Nuclear Information System (INIS)

    The acoustic emission monitoring and corroborative ultrasonic examination of the acoustic emission (AE) locations established during the hydrostatic pressure test of a BWR primary pressure vessel is described. Descriptive information regarding AE is provided as a background and details of the AE and ultrasonic instrumentation, procedures, problems encountered, and test results are discussed. In total, 42 acoustic emission locations were detected, located, and ultrasonically examined during this project. At all 42 AE locations ultrasonic indications were obtained. Of the AE locations, 76% (or 32 of the 42) were confirmed at amplitudes greater than or equal to 2.5% Distance Amplitude Correction (DAC) by either L-wave or shear wave ultrasonic examination, the largest of these being 18% DAC. The remainder of the AE locations were confirmed at amplitudes less than 2.5% DAC. ASME Code requires that ultrasonic examination record for permanent reference indications of 50% DAC or greater. As is to be expected ultrasonic examination detected examinations which were not located by AE monitoring since AE locates only active flaws. Results show the complementary value of AE monitoring to ultrasonic examination in two primary uses: determining the existence and the location of active discontinuities; and assuring that active discontinuities are not overlooked. Results reflect the position that AE monitoring and ultrasonics are supplementary to each other, not replacements for one another

  20. Ultrasonic examination of welded joints of great thickness in mechanical equipment under pressure

    Science.gov (United States)

    Emil, N.

    1974-01-01

    The requirements involved in choosing ultrasonic devices, the factors that affect testing, and recommended calibration methods are discussed. The ultrasonic testing method is the only method that up to now permits detection of defects in welded joints of great thickness. The results are conditioned by the performances of the devices employed as well as by the degree of instruction of the personnel.

  1. Ultrasonic Cutting of Foods

    Science.gov (United States)

    Schneider, Yvonne; Zahn, Susann; Rohm, Harald

    In the field of food engineering, cutting is usually classified as a mechanical unit operation dealing with size reduction by applying external forces on a bulk product. Ultrasonic cutting is realized by superpositioning the macroscopic feed motion of the cutting device or of the product with a microscopic vibration of the cutting tool. The excited tool interacts with the product and generates a number of effects. Primary energy concentration in the separation zone and the modification of contact friction along the tool flanks arise from the cyclic loading and are responsible for benefits such as reduced cutting force, smooth cut surface, and reduced product deformation. Secondary effects such as absorption and cavitation originate from the propagation of the sound field in the product and are closely related to chemical and physical properties of the material to be cut. This chapter analyzes interactions between food products and ultrasonic cutting tools and relates these interactions with physical and chemical product properties as well as with processing parameters like cutting velocity, ultrasonic amplitude and frequency, and tool design.

  2. Sharpening of ultrasonic scalers.

    Science.gov (United States)

    Checchi, L; Pelliccioni, G A; D'Achille, C

    1991-08-01

    Instruments suitable for removing calculus, plaque and necrotic cementum, which hinder normal periodontal reattachment, are extremely important for successful therapy. The test was carried out in order to see if a standard scaler used for ultrasonic tartar removal maintains its physical features when sharpened. 6 scalers, compatible with piezo-electric generators, were tested and 2 diameters, A and B, weights and resonance frequencies were measured. Scalers no. 2, 3, 4, 5, were sharpened and was used as control. All measurements were taken again at the end of the test. Statistical analysis reveals significant variations, after sharpening, of A diameter (t = 4.14 greater than 3.55, p less than 0.01), B diameter (t = 5.34 greater than 3.355, p less than 0.01) and resonance frequency (t = 2.82 greater than 2.306, p less than 0.05); in contrast, there is no significant change of weights (t = 1.17 less than 2.306, p greater than 0.05). These results suggest that sharpening slightly modifies the physical features of ultrasonic tips, so that sharpening ultrasonic scalers, from a physical point of view, can be carried out, paying attention not to damage the water cooling system. PMID:1894743

  3. Ultrasonic investigations in intermetallics

    Indian Academy of Sciences (India)

    Devraj Singh; D K Pandey

    2009-02-01

    Ultrasonic attenuation for the longitudinal and shear waves due to phonon–phonon interaction and thermoelastic mechanism have been evaluated in B2 structured in-termetallic compounds AgMg, CuZr, AuMg, AuTi, AuMn, AuZn and AuCd along $\\langle 1 0 0 \\rangle, \\langle 1 1 1 \\rangle and \\langle 1 1 0 \\rangle crystallographic directions at room temperature. For the same evaluations, second- and third-order elastic constants, ultrasonic velocities, Grüneisen parameters, non-linearity parameter, Debye temperature and thermal relaxation time are also computed. Although the molecular weight of these materials increases from AgMg to AuCd, the obtained results are affected with the deviation number. Attenuation of ultrasonic waves due to phonon–phonon interaction is predominant over thermoelastic loss. Results are compared with available theoretical and experimental results. The results with other well-known physical properties are useful for industrial purposes.

  4. Nondestructive evaluation ultrasonic methods for construction materials

    International Nuclear Information System (INIS)

    The paper presents some ultrasonic methods for evaluation of physical-mechanical properties of construction materials (bricks, concrete, BCA), such as: pulse method, examination methods, and direct measurement of the propagation velocity and impact-echo method. Utilizing these nondestructive evaluation ultrasonic methods it can be determined the main material parameters and material characteristics (elasticity coefficients, density, propagation velocity, ultrasound attenuation, etc.) of construction materials. These method are suitable for construction materials because the defectoscopy methods for metallic materials cannot be utilized, due to its rugged and non-homogeneous structures and grate attenuation coefficients of ultrasound propagation through materials. Also, the impact-echo method is a technique for flaw detection in concrete based on stress wave propagation. Studies have shown that the impact-echo method is effective for locating voids, honeycombing, delaminating, depth of surface opening cracks, and measuring member thickness

  5. Improved ultrasonic nondestructive testing of pressure vessels

    International Nuclear Information System (INIS)

    Progress in the development of synthetic aperture imaging techniques and a flaw detection technique for ultrasonic pulse-echo flaw evaluation is described. Synthetic aperture test results using narrow-beam probes show increased signal-to-noise ratios. Processing times for synthetic apertures constructed with wide-beam probes have been reduced. Results of deconvolution combined with synthetic aperture processing show enhanced resolution. Also included are images from scans over curved surfaces, initial results of a parameter study, a method for flaw detection based on time series models, and progress in the development of graphical displays

  6. Ultrasonic tetsing of contact tube welds

    International Nuclear Information System (INIS)

    A method of complex testing of quality of welded joints of TPP and NPP heat-exchange tubes has beer developed. It consists of ultrasonic flaw detection in combination with selective fractographic analysis, envisaging the detection of continuity disturbance and assessment of metal structural state. If there is no continuity disturbance in fractures but there is a macrocrystalline structure (the part of shining facets is more than 30%) the series of products is found to be a low-quality one according to structural state of welded joints metal

  7. New Approach to Ultrasonic Spectroscopy Applied to Flywheel Rotors

    Science.gov (United States)

    Harmon, Laura M.; Baaklini, George Y.

    2002-01-01

    Flywheel energy storage devices comprising multilayered composite rotor systems are being studied extensively for use in the International Space Station. A flywheel system includes the components necessary to store and discharge energy in a rotating mass. The rotor is the complete rotating assembly portion of the flywheel, which is composed primarily of a metallic hub and a composite rim. The rim may contain several concentric composite rings. This article summarizes current ultrasonic spectroscopy research of such composite rings and rims and a flat coupon, which was manufactured to mimic the manufacturing of the rings. Ultrasonic spectroscopy is a nondestructive evaluation (NDE) method for material characterization and defect detection. In the past, a wide bandwidth frequency spectrum created from a narrow ultrasonic signal was analyzed for amplitude and frequency changes. Tucker developed and patented a new approach to ultrasonic spectroscopy. The ultrasonic system employs a continuous swept-sine waveform and performs a fast Fourier transform on the frequency spectrum to create the spectrum resonance spacing domain, or fundamental resonant frequency. Ultrasonic responses from composite flywheel components were analyzed at Glenn to assess this NDE technique for the quality assurance of flywheel applications.

  8. Application of low intensity ultrasonics to cheese manufacturing processes.

    Science.gov (United States)

    Benedito, J; Carcel, J A; Gonzalez, R; Mulet, A

    2002-05-01

    Ultrasound has been used to non-destructively assess the quality of many foods such as meat, fish, vegetables and dairy products. This paper addresses the applications of low intensity ultrasonics in the cheese manufacturing processes and highlights the areas where ultrasonics could be successfully implemented in the future. The decrease of ultrasonic attenuation during the renneting process can be used to determine the optimum cut time for cheese making. The ultrasonic velocity increases during maturation for those types of cheese that become harder during this manufacturing stage, thus being an indicator of the maturity degree. Moreover, ultrasonic measurements could be linked to sensory parameters. From the ultrasonic velocity measurements at two different temperatures, it is possible to assess cheese composition, thus allowing an improvement in the quality and uniformity of cheese commercialization. In addition, in pulse-echo mode it is possible to detect cracked pieces due to abnormal fermentations and also to assess the distance of the crack from the surface. PMID:12159930

  9. Study of ultrasonic thermometry based on ultrasonic time-of-flight measurement

    OpenAIRE

    Ruixi Jia; Qingyu Xiong; Lijie Wang; Kai Wang; Xuehua Shen; Shan Liang; Xin Shi

    2016-01-01

    Ultrasonic thermometry is a kind of acoustic pyrometry and it has been evolving as a new temperature measurement technology for various environment. However, the accurate measurement of the ultrasonic time-of-flight is the key for ultrasonic thermometry. In this paper, we study the ultrasonic thermometry technique based on ultrasonic time-of-flight measurement with a pair of ultrasonic transducers for transmitting and receiving signal. The ultrasonic transducers are installed in a single path...

  10. Fatigue crack monitoring in multi-layered aircraft structures using guided ultrasonic waves

    OpenAIRE

    Koston, E.

    2010-01-01

    The detection of fatigue cracks at fasteners in the sub layers of multi-layered aircraft structures can be problematic using conventional nondestructive testing methods. In this thesis the sensitivity of low frequency guided ultrasonic waves to detect these defects is studied. Guided ultrasonic waves typically have energy distributed through the thickness of such structures and allow for defect detection in all sub-layers, but have wavelengths larger than commonly used in bulk wave ...

  11. Ultrasonic Examination of AN Austenitic Weld: Illustration of the Disturbances of the Ultrasonic Beam

    Science.gov (United States)

    Chassignole, B.; Dupond, O.; Doudet, L.; Duwig, V.; Etchegaray, N.

    2009-03-01

    The ultrasonic examination of the primary coolant piping of Pressurized Water Reactors (PWR) is an important challenge for the nuclear industry. Numerous studies were undertaken by EDF R&D for a few years to improve the NDT process on these applications and to help to their qualification. More particularly, a great deal was made on the examination of the austenitic stainless steel welds. Indeed, the anisotropic, heterogeneous and coarse granular structures of these welds lead to important disturbances of the ultrasonic propagation. This paper presents some examples of the experimental and numerical studies which allowed to highlight the different disturbances (beam deviation, division and attenuation). We pay more attention on spurious echoes which may appear when a plane defect is located in an austenitic weld. The experimental approach is based on tests on mock-ups containing artificial defects. On the other hand, a numerical approach with the finite element code ATHENA, developed by EDF, allows to explain the origin of the disturbances. We show the interest of this tool to carry out a close analysis of the ultrasonic mode conversions in the complex structure of the weld which produce the spurious echoes. Finally, the influence of the ultrasonic disturbances on performances in term of detection of the defects is discussed.

  12. Innovative ultrasonics for power plant commissioning

    International Nuclear Information System (INIS)

    During the commissioning of a nuclear power plant, the usual role of ultrasonics is associated with nondestructive testing of welds. There is, however, a variety of undesirable conditions associated with the fluids carried through the various reactor systems which may be just as important to station operation. A variety of unusual ultrasonic techniques has been developed for testing fluid systems at the Point Lepreau Generating Station. This paper uses the experience gained at the Point Lepreau reactor to illustrate the valuable information which can be gained from these measurements, such as: fluid level in pipes and headers; fluid level in pressure vessels; detection, and sizing of debris in pipes; in situ measurement and verification of orifice condition; detection and location of cavitation, water hammer, valve leakage; quantitative measurement of gate movement within the body of an inservice valve; determination of valve position; detection and imaging of flow separation; detection and location of leaks in concrete containment structures; verification of design flows; balancing of loop flows; and detection of low flow. The application of these techniques at other reactor sites is also discussed

  13. Mobile ultrasonic testing in pipes

    International Nuclear Information System (INIS)

    The paper deals with the development of the ultrasonic test method, in particular with the functioning of the impulse reflection method which is used for weld testing and wall thickness measurement in pipeline construction. The paper closes on a few remarks on ultrasonic testing in plastic tubes and some other special testing problems. (RW)

  14. Hydrogen attack evaluation of boiler tube using ultrasonic wave

    International Nuclear Information System (INIS)

    The presence of hydrogen in industrial plants is a source of damage. Hydrogen attack is one such form of degradation and often causing large tube ruptures that necessitate an immediate shutdown. Hydrogen attack may reduce the fracture toughness as well as the strength of steels. This reduction is caused partially by the presence of cavities and microcracks at the grain boundaries. In the past several techniques have been used with limited results. This paper describes the application of an ultrasonic velocity, attenuation and backscatter techniques for detecting the presence of hydrogen damage in utility boiler tubes. Ultrasonic tests showed a decrease in wave velocity and an increase in attenuation. Such results demonstrate the potential for ultrasonic nondestructive testing to quantify damage. Based on this study, recommendations are that both velocity and attenuation be used to detect hydrogen attack in steels.

  15. Development of a bank for ultrasonic characterization of olive oil

    International Nuclear Information System (INIS)

    Olive oil has long been renowned for its nutritional and healthy values. These values are being continuously verified by new scientific results. Not all olive oils found in the market are, however,authentic. One of the ways to cheat in olive oil is to mix it with other, cheaper oils. The aim of our study is to develop an ultrasonic measurement system that would quickly detect the fraud in the olive oil and thus protect and preserve this quality product. By using ultrasonic waves of frequency 1.7MHz in transmission through the oils, we have obtained promising results for detection of different mixtures of olive oil with pure sunflower oil. Our results have shown an increasing ultrasonic speed for an increasing percentage of sunflower oil in the mixture. (author)

  16. The application research of laser ultrasonic technique used in testing compound material

    Science.gov (United States)

    Xu, Jun; Kong, Lingjian; Gu, Xiaofei; Luo, Jijun; Hou, Xun

    2005-01-01

    The principles of laser ultrasonic generation and measurements with pulsed laser are presented. There are two kinds of means to actuate ultrasonic pulse: elasticity actuating and ablation actuating. The progress in laser ultrasonic about laser ultrasound generation, detection, propagation and its applications is introduced briefly. Applications in the field of Non-Destructive Testing (NDT) are reviewed. In the field of Non-Destructive Testing, according to the principle, the laser ultrasonic testing system consists of laser system, laser interferometer, photoelectric detector and receiving system with signal amplifier. Thus, long-range and non-contact on-line detection of ultrasonic testing system was realized. In view of some of the problems, the developing trends of such techniques are analyzed.

  17. 超超临界机组锅炉异种钢小径管镍基焊接接头超声波检测%Ultrasonic Flaw Detection of Dissimilar Steel Small-Diameter Tube Nickel-Based Welding Joint of Boiler of Ultra-Supercritical Units

    Institute of Scientific and Technical Information of China (English)

    邓宏平; 龙会国; 邹健伟; 谢亿

    2012-01-01

    针对超声检测火力发电厂锅炉小径管奥氏体钢与低合金钢对接异种钢焊缝的技术难题,文章通过理论分析、试验研究及现场检测验证,研究了常规小径管探头异种钢焊缝超声波检测方法。结果表明,对于如熔合线裂纹类缺陷选用小角度探头(K1~1.5)效果较佳;对于焊缝内缺陷宜选用大角度探头(K2~2.5)。利用该方法能有效检测出焊缝内各种缺陷,保证了机组安全运行也取得了较好的经济效益,对异种钢焊缝小径管超声波检测具有较强的借鉴意义。%In order to solve the ultrasonic testing technical problem of dissimilar steel small diameter tube nickel butt welding of austenitic steel and low alloy steel in thermal power plant, one new ultrasonic inspection method with small diameter tube adapted ultrasonic probe was researched by theory verification, experimental data and field experience. The results showed that the degrees of the influences of different defects on ultrasonic testing parameters were different. Better sensitivity for the fusion zone cracking in dissimilar steel small-diameter tube welding joint testing was obtained when K value of transverse wave probe was small, such as KI~I. 5. And it is good that K value of transverse wave probe was big {K2~2. 5) for internal defects in dissimilar steel small-diameter tube welding joint testing. This detective means had good detection effect for various excessive weld defects, which could ensure the safe operation of power units, improve economic benefits. The detection method mentioned in this paper could give assistance to the ultrasonic testing of dissimilar steel small-diameter tube welds.

  18. Ultrasonic inspection of austenitic welds

    International Nuclear Information System (INIS)

    The ultrasonic examination of austenitic stainless steel weld metal has always been regarded as a difficult proposition because of the large and variable ultrasonic attenuations and back scattering obtained from apparently similar weld deposits. The work to be described shows how the existence of a fibre texture within each weld deposit (as a result of epitaxial growth through successive weld beads) produces a systematic variation in the ultrasonic attenuation coefficient and the velocity of sound, depending upon the angle between the ultrasonic beam and the fibre axis. Development work has shown that it is possible to adjust the welding parameters to ensure that the crystallographic texture within each weld is compatible with improved ultrasonic transmission. The application of the results to the inspection of a specific weld in type 316 weld metal is described

  19. Ultrasonic dyeing of cellulose nanofibers.

    Science.gov (United States)

    Khatri, Muzamil; Ahmed, Farooq; Jatoi, Abdul Wahab; Mahar, Rasool Bux; Khatri, Zeeshan; Kim, Ick Soo

    2016-07-01

    Textile dyeing assisted by ultrasonic energy has attained a greater interest in recent years. We report ultrasonic dyeing of nanofibers for the very first time. We chose cellulose nanofibers and dyed with two reactive dyes, CI reactive black 5 and CI reactive red 195. The cellulose nanofibers were prepared by electrospinning of cellulose acetate (CA) followed by deacetylation. The FTIR results confirmed complete conversion of CA into cellulose nanofibers. Dyeing parameters optimized were dyeing temperature, dyeing time and dye concentrations for each class of the dye used. Results revealed that the ultrasonic dyeing produced higher color yield (K/S values) than the conventional dyeing. The color fastness test results depicted good dye fixation. SEM analysis evidenced that ultrasonic energy during dyeing do not affect surface morphology of nanofibers. The results conclude successful dyeing of cellulose nanofibers using ultrasonic energy with better color yield and color fastness results than conventional dyeing. PMID:26964959

  20. Phased array ultrasonic technology (PAUT) contribution to detection and sizing of microbially influenced corrosion (MIC) of service water systems and shutdown coolers heat exchangers in OPG CANDU stations

    International Nuclear Information System (INIS)

    Three PAUT techniques [linear scan - longitudinal waves, sector scan -longitudinal waves and sector scan-transverse waves] were developed and validated to assess the MIC attack in service water systems (SWS) and shutdown coolers heat-exchangers (SDC-HX) of Darlington and Pickering CANDU stations. PAUT employs linear array probes with a frequency between 4-12 MHz, depending on surface conditions, component geometry and MIC size/category to be detected. Examples from lab validation and field trials are presented. Based on field trials results, the techniques were optimized and new cal blocks were manufactured. It was demonstrated for mid-length pipes and for SDC-HX, the PAUT is the best technique compared with D-meter conventional UT and with guided waves. The expected field accuracy is about 0.5 mm (0.020) for large MIC attack. The ligament evaluation is technically achievable for colonies / pin holes located 2 mm under the outer surface. Improvements were identified and implemented for the next outages. (author)

  1. Phased array ultrasonic technology (PAUT) contribution to detection and sizing of microbially influenced corrosion (MIC) of service water systems and shutdown coolers heat exchangers in OPG CANDU stations

    Energy Technology Data Exchange (ETDEWEB)

    Ciorau, P.; Pullia, L.; Hazelton, T., E-mail: peter.ciorau@opg.com, E-mail: lou.pullia@opg.com, E-mail: trek.hazelton@opg.com [Ontario Power Generation, Toronto, Ontario (Canada); Daks, W. [CAD WIRE, Markham, Ontario (Canada)

    2008-07-01

    Three PAUT techniques [linear scan - longitudinal waves, sector scan -longitudinal waves and sector scan-transverse waves] were developed and validated to assess the MIC attack in service water systems (SWS) and shutdown coolers heat-exchangers (SDC-HX) of Darlington and Pickering CANDU stations. PAUT employs linear array probes with a frequency between 4-12 MHz, depending on surface conditions, component geometry and MIC size/category to be detected. Examples from lab validation and field trials are presented. Based on field trials results, the techniques were optimized and new cal blocks were manufactured. It was demonstrated for mid-length pipes and for SDC-HX, the PAUT is the best technique compared with D-meter conventional UT and with guided waves. The expected field accuracy is about 0.5 mm (0.020{sup )} for large MIC attack. The ligament evaluation is technically achievable for colonies / pin holes located 2 mm under the outer surface. Improvements were identified and implemented for the next outages. (author)

  2. Azimuthal-angle dependence of charged-pion-interferometry measurements with respect to second- and third-order event planes in Au+Au collisions at √[S(NN)]=200  GeV.

    Science.gov (United States)

    Adare, A; Afanasiev, S; Aidala, C; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Alexander, J; Aoki, K; Aramaki, Y; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bickley, A A; Bok, J S; Boyle, K; Brooks, M L; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Camacho, C M; Campbell, S; Chen, C-H; Chi, C Y; Chiu, M; Choi, I J; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; Connors, M; Constantin, P; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Denisov, A; Deshpande, A; Desmond, E J; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Finger, M; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Garishvili, I; Glenn, A; Gong, H; Gonin, M; Goto, Y; Granier de Cassagnac, R; Grau, N; Greene, S V; Grosse Perdekamp, M; Gunji, T; Gustafsson, H-Å; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Hartouni, E P; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Ide, J; Ikeda, Y; Imai, K; Inaba, M; Isenhower, D; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Jacak, B V; Jia, J; Jin, J; Johnson, B M; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kang, J H; Kapustinsky, J; Karatsu, K; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kim, B I; Kim, D H; Kim, D J; Kim, E; Kim, E-J; Kim, S H; Kim, Y-J; Kinney, E; Kiriluk, K; Kiss, A; Kistenev, E; Kochenda, L; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kozlov, A; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K; Lee, K B; Lee, K S; Leitch, M J; Leite, M A L; Leitner, E; Lenzi, B; Li, X; Liebing, P; Linden Levy, L A; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Love, B; Luechtenborg, R; Lynch, D; Maguire, C F; Makdisi, Y I; Malakhov, A; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; Means, N; Meredith, B; Miake, Y; Mignerey, A C; Mikeš, P; Miki, K; Milov, A; Mishra, M; Mitchell, J T; Mohanty, A K; Morino, Y; Morreale, A; Morrison, D P; Moukhanova, T V; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, T; Nakano, K; Newby, J; Nguyen, M; Niida, T; Nouicer, R; Nyanin, A S; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, I H; Park, J; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J-C; Pereira, H; Peresedov, V; Peressounko, D Yu; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Purwar, A K; Qu, H; Rak, J; Rakotozafindrabe, A; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Rosnet, P; Rukoyatkin, P; Ružička, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Semenov, A Yu; Seto, R; Sharma, D; Shein, I; Shibata, T-A; Shigaki, K; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Sparks, N A; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sziklai, J; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tarján, P; Themann, H; Thomas, T L; Todoroki, T; Togawa, M; Toia, A; Tomášek, L; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Vinogradov, A A; Virius, M; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Wood, J P; Woody, C L; Wright, R M; Wysocki, M; Xie, W; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zolin, L

    2014-06-01

    Charged-pion-interferometry measurements were made with respect to the second- and third-order event plane for Au+Au collisions at sqrt[s_{NN}]=200  GeV. A strong azimuthal-angle dependence of the extracted Gaussian-source radii was observed with respect to both the second- and third-order event planes. The results for the second-order dependence indicate that the initial eccentricity is reduced during the medium evolution, which is consistent with previous results. In contrast, the results for the third-order dependence indicate that the initial triangular shape is significantly reduced and potentially reversed by the end of the medium evolution, and that the third-order oscillations are largely dominated by the dynamical effects from triangular flow. PMID:24949761

  3. Azimuthal-angle dependence of charged-pion-interferometry measurements with respect to 2$^{\\rm nd}$- and $3^{\\rm rd}$-order event planes in Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV

    CERN Document Server

    Adare, A; Aidala, C; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Alexander, J; Aoki, K; Aramaki, Y; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bickley, A A; Bok, J S; Boyle, K; Brooks, M L; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Camacho, C M; Campbell, S; Chen, C -H; Chi, C Y; Chiu, M; Choi, I J; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; Connors, M; Constantin, P; Csanád, M; Csörgő, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Denisov, A; Deshpande, A; Desmond, E J; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Jr., \\,; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Garishvili, I; Glenn, A; Gong, H; Gonin, M; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Perdekamp, M Grosse; Gunji, T; Gustafsson, H -Å; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Hartouni, E P; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Ide, J; Ikeda, Y; Imai, K; Inaba, M; Isenhower, D; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanischev, D; Jacak, B V; Jia, J; Jin, J; Johnson, B M; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kang, J H; Kapustinsky, J; Karatsu, K; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kim, B I; Kim, D H; Kim, D J; Kim, E; Kim, E -J; Kim, S H; Kim, Y -J; Kinney, E; Kiriluk, K; Kiss, Á; Kistenev, E; Kochenda, L; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kozlov, A; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K; Lee, K B; Lee, K S; Leitch, M J; Leite, M A L; Leitner, E; Lenzi, B; Li, X; Liebing, P; Levy, L A Linden; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Love, B; Luechtenborg, R; Lynch, D; Maguire, C F; Makdisi, Y I; Malakhov, A; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; Means, N; Meredith, B; Miake, Y; Mignerey, A C; Mikeš, P; Miki, K; Milov, A; Mishra, M; Mitchell, J T; Mohanty, A K; Morino, Y; Morreale, A; Morrison, D P; Moukhanova, T V; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, T; Nakano, K; Newby, J; Nguyen, M; Niida, T; Nouicer, R; Nyanin, A S; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, I H; Park, J; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J -C; Pereira, H; Peresedov, V; Peressounko, D Yu; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Purwar, A K; Qu, H; Rak, J; Rakotozafindrabe, A; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Rosnet, P; Rukoyatkin, P; Ružička, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Semenov, A Yu; Seto, R; Sharma, D; Shein, I; Shibata, T -A; Shigaki, K; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Sparks, N A; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sziklai, J; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, Y; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tarján, P; Themann, H; Thomas, T L; Todoroki, T; Togawa, M; Toia, A; Tomášek, L; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Vinogradov, A A; Virius, M; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Wood, J P; Woody, C L; Wright, R M; Wysocki, M; Xie, W; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zhang, C; Zhou, S; Zolin, L

    2014-01-01

    Charged-pion-interferometry measurements were made with respect to the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event plane for Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV. A strong azimuthal-angle dependence of the extracted Gaussian-source radii was observed with respect to both the 2$^{\\rm nd}$- and 3$^{\\rm rd}$-order event planes. The results for the 2$^{\\rm nd}$-order dependence indicate that the initial eccentricity is reduced during the medium evolution, but not reversed in the final state, which is consistent with previous results. In contrast, the results for the 3$^{\\rm rd}$-order dependence indicate that the initial triangular shape is significantly reduced and potentially reversed by the end of the medium evolution, and that the 3$^{\\rm rd}$-order oscillations are largely dominated by the dynamical effects from triangular flow.

  4. Ultrasonic testing device

    International Nuclear Information System (INIS)

    The ultrasonic testing system serves to inspect welds and the adjoining heat-affected zones on reactor pressure vessels. The three-oscillator search unit has got either two external emitter crystal oscillators simultaneously loaded and an internal receiver crystal oscillator of equal width or vice versa. The inspection path is run through meanderingly. With the search unit there is succeeded to do the inspection by SEL technique, by SE technique with shear waves or by tandem technique. Loading of the oscillators is done with a time-multiplex method. (RW)

  5. Internal properties assessment in agar wood trees using ultrasonic velocity measurement

    International Nuclear Information System (INIS)

    This paper presents the application of ultrasonic velocity in agar wood trees (Aquilaria crassna) with the purpose of evaluating the relationship of the ultrasonic velocity to the variations of internal properties of trees. In this study, three circular cross-sectional discs from the freshly cut tree were selected as samples. First sample with a big hole (decay) in the middle, second sample with internal resinous and the last one is the sample with no defects. The through transmission ultrasonic testing method was carried out using Tico ultrasonic pulse velocity tester which is from Switzerland. Two-dimensional image of internal properties evaluation by an ultrasonic investigation was obtained using Matlab. The results showed that the ultrasonic wave cannot pass through the internal decay or resinous so that the wave went round it and thus ultrasonic wave velocity significantly decreased by increasing the hole or resinous. The difference in color of the image generated by Matlab software based on variation of ultrasonic velocity between the internal decay area and its surrounding area was obvious. Therefore, the properties of internal properties of the three could be detected by ultrasonic line imaging technique. (author)

  6. Ultrasonic Evaluation of Two Dissimilar Metal Weld Overlay Specimens

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Susan L.; Cinson, Anthony D.; Prowant, Matthew S.; Moran, Traci L.; Anderson, Michael T.

    2012-06-30

    Two dissimilar metal weld (DMW) pipe-to-nozzle specimens were implanted with thermal fatigue cracks in the 13% to 90% through-wall depth range. The specimens were ultrasonically evaluated with phased-array probes having center frequencies of 0.8, 1.0, 1.5, and 2.0 megahertz (MHz). An Alloy 82/182 weld overlay (WOL) was applied and the specimens were ultrasonically re-evaluated for flaw detection and characterization. The Post-WOL flaw depths were approximately 10% to 56% through-wall. This study has shown the effectiveness of ultrasonic examinations of Alloy 82/182 overlaid DMW specimens. Phased-array probes with center frequency in the 0.8- to 1.0-MHz range provide a strong coherent signal but the greater ultrasonic wavelength and larger beam spot size prevent the reliable detection of small flaws. These small flaws had nominal through-wall depths of less than 15% and length in the 50-60 mm (2-2.4 in.) range. Flaws in the 19% and greater through-wall depth range were readily detected with all four probes. At the higher frequencies, the reflected signals are less coherent but still provide adequate signal for flaw detection and characterization. A single inspection at 2.0 MHz could provide adequate detection and sizing information but a supplemental inspection at 1.0 or 1.5 MHz is recommended.

  7. Ultrasonic Inspection Of Welds On Tube Fittings

    Science.gov (United States)

    Ray, Arjun N.; Nummelin, John L.

    1996-01-01

    Scanning ultrasonic apparatus designed for use in nondestructive inspection of electron-beam welds between heat-exchanger tube and end fittings. Includes ultrasonic probe, scanning mechanism, ultrasonic-signal-generating and -processing circuits, and computers. Not necessary to immerse any part of apparatus or tube/fitting assembly in water during inspection. Output ultrasonic-test signals displayed on computer to reveal defects.

  8. Ultrasonic Guided Wave Simulation Toolbox for Virtual Inspection of Composites Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Ultrasonic guided wave nondestructive evaluation (NDE) techniques are being used to detect flaws and damage in fracture critical structures such as composites. In...

  9. Vibration in The Ultrasonic Machining System

    Science.gov (United States)

    Zhang, Nan; Chen, Zhigang; Zhong, Xinrong

    The rotary ultrasonic machining system is the vibration system, using the characteristics of the ultrasonic resonance. Based on the ultrasonic vibration model, the dynamic characteristics of the ultrasonic machining system are analyzed, and using the wave equations, the dynamic characteristics of the horn with the exponential transition are analyzed. Based on FEM, the dynamic characteristics of the horn with the exponential transition in the rotary ultrasonic machining system are analyzed.

  10. Ultrasonic testing of turbine rotors with hooped disks

    International Nuclear Information System (INIS)

    Alsthom-Atlantique has developed ultrasonic testing methods for in-service inspection of the low-pressure rotors of 900 MW steam turbines; they allow to detect fatigue cracks which grow from the rotor shaft/disk interface, either within the shaft, or in the disks, without removing the disks

  11. Transferring manual ultrasonic inspection procedures - results of a pilot study

    International Nuclear Information System (INIS)

    Results of a manual ultrasonic pilot study for NDE specialists at RBMK nuclear reactor sites are presented. Probabilities of detection and false calls, using two different grading criteria, are estimated. Analyses of performance parameters lead to conclusions regarding attributes for improved test discrimination capabilities. (orig.)

  12. An ultrasonic method for the internal inspection of tubing

    International Nuclear Information System (INIS)

    An ultrasonic inspection to complete eddy current testing is proposed. Devices that can measure thickness and detect flaws without the need to rotate a transducer are described. A procedure taking into account the lack of precision of the measurements is presented

  13. Transferring manual ultrasonic inspection procedures - results of a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M.; Taylor, T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kadenko, I. [Ukraine Nondestructive Training and Certification Facility (Ukraine)

    2002-07-01

    Results of a manual ultrasonic pilot study for NDE specialists at RBMK nuclear reactor sites are presented. Probabilities of detection and false calls, using two different grading criteria, are estimated. Analyses of performance parameters lead to conclusions regarding attributes for improved test discrimination capabilities. (orig.)

  14. Nonlinear Time Reversal Ultrasonic Pseudo-Tomography

    Czech Academy of Sciences Publication Activity Database

    Převorovský, Zdeněk; Krofta, Josef; Převorovský, David

    2008-01-01

    Roč. 13, č. 3 (2008), s. 1-13. ISSN 1435-4934. [NDT in Progress. Praha, 05.11.2007-07.11.2007] R&D Projects: GA ČR GA106/07/1393; GA MPO FT-TA/026 Institutional research plan: CEZ:AV0Z20760514 Keywords : defect detection * nonlinear ultrasonic spectroscopy * time reversal mirror Subject RIV: BI - Acoustics http://www.ndt.net/search/docs.php3?showForm=off&edit=1&MainSource=53&AuthorID=2812

  15. Properties of ultrasonic testing systems

    International Nuclear Information System (INIS)

    For a long time, ultrasonic testing of reactor components and plants whose safety had to meet high demands, lacked definitions of the required properties of the ultrasonic testing system. The standard draft DIN 25 450 states demands on the ultrasonic testing unit and the test heads and recommends measuring methods to determine their properties. With test units and test heads meeting the demands of the draft a better reproducibility of the test is obtained than before; the improved test statement results in an increased safety during production and operation of components and plants. (orig./HP)

  16. Fundamentals of ultrasonic phased arrays

    CERN Document Server

    Schmerr, Lester W

    2014-01-01

    This book describes in detail the physical and mathematical foundations of ultrasonic phased array measurements.?The book uses linear systems theory to develop a comprehensive model of the signals and images that can be formed with phased arrays. Engineers working in the field of ultrasonic nondestructive evaluation (NDE) will find in this approach a wealth of information on how to design, optimize and interpret ultrasonic inspections with phased arrays. The fundamentals and models described in the book will also be of significant interest to other fields, including the medical ultrasound and

  17. Pulsed ultrasonic stir welding method

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2013-01-01

    A method of performing ultrasonic stir welding uses a welding head assembly to include a plate and a rod passing through the plate. The rod is rotatable about a longitudinal axis thereof. In the method, the rod is rotated about its longitudinal axis during a welding operation. During the welding operation, a series of on-off ultrasonic pulses are applied to the rod such that they propagate parallel to the rod's longitudinal axis. At least a pulse rate associated with the on-off ultrasonic pulses is controlled.

  18. Attenuation of ultrasonic Rayleigh–Lamb waves by small horizontal defects in thin aluminium plates

    OpenAIRE

    Gilchrist, M. D.

    1999-01-01

    The present paper illustrates how horizontal symmetric crack-like defects can be detected rapidly in thin isotropic plates by using longitudinal ultrasonic waves. The use of such longitudinal waves offers the potential of being significantly faster for non-destructively detecting defects than conventional ultrasonic techniques, which rely on transverse waves propagating through the thickness of a plate. Computational and analytical methods are used to predict reflection coefficients due to th...

  19. Attenuation characteristics of ultrasonic pulse in carbon/phenolic composite

    International Nuclear Information System (INIS)

    The presence of porosity in a fiber-reinforced composite may have a critical effect on the composite's mechanical properties and service performance. Detection and characterization of porosity by nondestructive, especially ultrasonic, testing have received considerable attention in recent years. In this paper, the velocity and attenuation of longitudinal and shear ultrasonic pulse in carbon/phenolic composite were measured using through-transmission technique. And the attenuation characteristics were determined and analyzed as a function of frequency. These results show that the main mechanism of attenuation is Rayleigh scattering from porosity and the change of the volume fraction of porosity is associated with that of attenuation slope.

  20. Flaw imaging and ultrasonic techniques for characterizing sintered silicon carbide

    Energy Technology Data Exchange (ETDEWEB)

    Baaklini, G.Y.; Abel, P.B.

    1987-08-01

    The capabilities were investigated of projection microfocus x-radiography, ultrasonic velocity and attenuation, and reflection scanning acoustic microscopy for characterizing silicon carbide specimens. Silicon carbide batches covered a range of densities and different microstructural characteristics. Room temperature, four point flexural strength tests were conducted. Fractography was used to identify types, sizes, and locations of fracture origins. Fracture toughness values were calculated from fracture strength and flaw characterization data. Detection capabilities of radiography and acoustic microscopy for fracture-causing flaws were evaluated. Applicability of ultrasonics for verifying material strength and toughness was examined.

  1. Automated ultrasonic shop inspection of reactor pressure vessel forgings

    International Nuclear Information System (INIS)

    Automated ultrasonic shop inspection utilizing a computer-controlled system is being applied to each of the forgings for the reactor pressure vessel of the proposed Sizewell B PWR power station. Procedures which utilize a combination of high sensitivity shear wave pulse echo, 0 degrees and 70 degrees angled longitudinal waves, tandem and through-thickness arrays have been developed to provide comprehensive coverage and an overall reliability of inspection comparable to the best achieved in UKAEA defect detection trials and in PISC II. This paper describes the ultrasonic techniques, the automated system (its design, commissioning and testing), validation and the progress of the inspections

  2. Inspection of pipeline girth welds with ultrasonic phased array technique

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A novel automatic ultrasonic system used for the inspection of pipeline girth welds is developed, in which a linear phased array transducer using electronic scan is adopted. Optimal array parameters are determined based on a mathematical model of acoustic field for linear phased array derived from Huygens' principle. The testing method and the system structure are introduced. The experimental results show that the phased array transducer system has the same detectability as that of conventional ultrasonic transducer system, but the system architecture can be simplified greatly, and the testing flexibility and the testing speed can be improved greatly.

  3. Modeling for ultrasonic testing accuracy in probabilistic fracture mechanics analysis

    International Nuclear Information System (INIS)

    This study proposes models for ultrasonic testing (UT) accuracy at In-service Inspection (ISI) in probabilistic fracture mechanics (PFM) analysis. Regression analysis of the data brought by Ultrasonic Test and Evaluation for Maintenance Standards (UTS) project and modeling for successful candidates of Performance demonstration certification system provided the models for accuracy of flaw detection and sizing. New PFM analysis code, which evaluates failure probabilities at weld lines in piping aged by Stress Corrosion Cracking, has been developed by JAEA. The models were introduced into the code. Failure probabilities under the UT models at a weld line were evaluated by the code. (author)

  4. Computer automation of ultrasonic testing. [inspection of ultrasonic welding

    Science.gov (United States)

    Yee, B. G. W.; Kerlin, E. E.; Gardner, A. H.; Dunmyer, D.; Wells, T. G.; Robinson, A. R.; Kunselman, J. S.; Walker, T. C.

    1974-01-01

    Report describes a prototype computer-automated ultrasonic system developed for the inspection of weldments. This system can be operated in three modes: manual, automatic, and computer-controlled. In the computer-controlled mode, the system will automatically acquire, process, analyze, store, and display ultrasonic inspection data in real-time. Flaw size (in cross-section), location (depth), and type (porosity-like or crack-like) can be automatically discerned and displayed. The results and pertinent parameters are recorded.

  5. Ultrasonic isolation of buried pipes

    Science.gov (United States)

    Leinov, Eli; Lowe, Michael J. S.; Cawley, Peter

    2016-02-01

    Long-range guided wave testing (GWT) is used routinely for the monitoring and detection of corrosion defects in above ground pipelines. The GWT test range in buried, coated pipelines is greatly reduced compared to above ground configurations due to energy leakage into the embedding soil. In this paper, the effect of pipe coatings on the guided wave attenuation is investigated with the aim of increasing test ranges for buried pipelines. The attenuation of the T(0,1) and L(0,2) guided wave modes is measured using a full-scale experimental apparatus in a fusion-bonded epoxy (FBE)-coated 8 in. pipe, buried in loose and compacted sand. Tests are performed over a frequency range typically used in GWT of 10-35 kHz and compared with model predictions. It is shown that the application of a low impedance coating between the FBE layer and the sand effectively decouples the influence of the sand on the ultrasound leakage from the buried pipe. Ultrasonic isolation of a buried pipe is demonstrated by coating the pipe with a Polyethylene (PE)-foam layer that has a smaller impedance than both the pipe and sand, and has the ability to withstand the overburden load from the sand. The measured attenuation in the buried PE-foam-FBE-coated pipe is found to be substantially reduced, in the range of 0.3-1.2 dB m-1 for loose and compacted sand conditions, compared to measured attenuation of 1.7-4.7 dB m-1 in the buried FBE-coated pipe without the PE-foam. The acoustic properties of the PE-foam are measured independently using ultrasonic interferometry and incorporated into model predictions of guided wave propagation in buried coated pipe. Good agreement is found between the experimental measurements and model predictions. The attenuation exhibits periodic peaks in the frequency domain corresponding to the through-thickness resonance frequencies of the coating layer. The large reduction in guided wave attenuation for PE-coated pipes would lead to greatly increased GWT test ranges; such

  6. Application of Ultrasonic Detection Technology for Inner Wall Oxide Layer Thickness Measurement in Thermal Power Industry%内壁氧化膜超声波检测技术在火力发电行业的应用

    Institute of Scientific and Technical Information of China (English)

    邱燕飞; 金学峰; 张启礼

    2015-01-01

    The basic principle and equipment performance of heating surface tube inner wall oxide layer ultrasonic detection technology is introduced. This technique can be used as a rapid and accurate measurement of inner wall oxide layer thickness, which is suitable for batch testing. In addition, the speciifc application of this technology in furnace tube metal layer thickness measurement, the inner wall oxide layer dynamic monitoring, equivalent temperature calculation and furnace tube life prediction is discussed and analyzed in detail. This technology can provide support for furnace tube security assessment and life prediction that could play an important role in guaranteeing the safe and economical operation of power plant boiler and inspection guidance, and has good application prospect in thermal power industry.%介绍了受热面管内壁氧化膜超声波检测技术的基本原理和仪器设备,该技术可对受热面管内壁氧化膜厚度进行快速、准确测量,适用于批量检测。在此基础上,进一步对该项技术在管壁金属层厚度测量、内壁氧化膜动态监测、当量温度计算以及炉管寿命预测方面的具体应用进行了较为详细地阐述和分析。通过检测内壁氧化膜厚度,对高温受热面管的安全状况进行评价、预测其剩余寿命,对于电站锅炉的安全经济运行、指导检验检修方面具有重要作用,在火力发电行业具有良好的应用前景。

  7. Ultrasonic decontamination robot

    International Nuclear Information System (INIS)

    A method is described of removing radioactive contamination from a primary fluid header of a steam generator between periods of active operation thereof, the header having a sealable access manway therein to permit access to interior surfaces of the header. The method consists of: inserting through the header manway into the interior thereof a robotic arm having a base portion sized to fit sealably in the manway, an ultrasonic decontamination head disposed to be movable at an end of the robotic arm, a solvent supply tube connected to the decontamination head, and a fluid removal conduit disposed at a low point in the interior of the header; sealing the base portion in the header manway

  8. Three-dimensional imaging of biological cells with picosecond ultrasonics

    Science.gov (United States)

    Danworaphong, Sorasak; Tomoda, Motonobu; Matsumoto, Yuki; Matsuda, Osamu; Ohashi, Toshiro; Watanabe, Hiromu; Nagayama, Masafumi; Gohara, Kazutoshi; Otsuka, Paul H.; Wright, Oliver B.

    2015-04-01

    We use picosecond ultrasonics to image animal cells in vitro—a bovine aortic endothelial cell and a mouse adipose cell—fixed to Ti-coated sapphire. Tightly focused ultrashort laser pulses generate and detect GHz acoustic pulses, allowing three-dimensional imaging (x, y, and t) of the ultrasonic propagation in the cells with ˜1 μm lateral and ˜150 nm depth resolutions. Time-frequency representations of the continuous-wavelet-transform amplitude of the optical reflectivity variations inside and outside the cells show GHz Brillouin oscillations, allowing the average sound velocities of the cells and their ultrasonic attenuation to be obtained as well as the average bulk moduli.

  9. Fractional Fourier Transform for Ultrasonic Chirplet Signal Decomposition

    Directory of Open Access Journals (Sweden)

    Yufeng Lu

    2012-01-01

    Full Text Available A fractional fourier transform (FrFT based chirplet signal decomposition (FrFT-CSD algorithm is proposed to analyze ultrasonic signals for NDE applications. Particularly, this method is utilized to isolate dominant chirplet echoes for successive steps in signal decomposition and parameter estimation. FrFT rotates the signal with an optimal transform order. The search of optimal transform order is conducted by determining the highest kurtosis value of the signal in the transformed domain. A simulation study reveals the relationship among the kurtosis, the transform order of FrFT, and the chirp rate parameter in the simulated ultrasonic echoes. Benchmark and ultrasonic experimental data are used to evaluate the FrFT-CSD algorithm. Signal processing results show that FrFT-CSD not only reconstructs signal successfully, but also characterizes echoes and estimates echo parameters accurately. This study has a broad range of applications of importance in signal detection, estimation, and pattern recognition.

  10. A Simple Model for Nonlinear Confocal Ultrasonic Beams

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dong; ZHOU Lin; SI Li-Sheng; GONG Xiu-Fen

    2007-01-01

    @@ A confocally and coaxially arranged pair of focused transmitter and receiver represents one of the best geometries for medical ultrasonic imaging and non-invasive detection. We develop a simple theoretical model for describing the nonlinear propagation of a confocal ultrasonic beam in biological tissues. On the basis of the parabolic approximation and quasi-linear approximation, the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation is solved by using the angular spectrum approach. Gaussian superposition technique is applied to simplify the solution, and an analytical solution for the second harmonics in the confocal ultrasonic beam is presented.Measurements are performed to examine the validity of the theoretical model. This model provides a preliminary model for acoustic nonlinear microscopy.

  11. Ultrasonic testing for transverse defects in mixed alloy seams

    International Nuclear Information System (INIS)

    In 2000, several defects in mixed welds were reported from abroad. Investigations showed that they were caused by stress corrosion cracking, usually in axial direction and at right angles to the circumferential direction of the welds. Ultrasonic testing is difficult because of the coarse grain structure, the crystal orientation, and the high degree of elastic anisotropy. Further, buffering between the ferritic material and the weld delays the propagation of ultrasonic waves. Currently, international research projects focus on improved signal processing and on optimized strategies for qualification of ultrasonic test methods. In the case of the qualification procedure currently applied at the EPRI center, phased arrays with 4'7 elements, a frequency of 1.5 MHz and an aperture of 12'20 mm are used. The test probe is mounted on the outer surface of the pipes and can detect defects on the inside. Parallel to the experiments, model calculations were carried out to validate the measured results. (orig.)

  12. Inservice surveillance and diagnostic ultrasonic system of steamgenerator tubing

    International Nuclear Information System (INIS)

    A versatile ultrasonic inspection systrem is described which can produce fast, accurate, bore-side non-destructive examination of tubes with a minimum inside diameter (ID) of 9mm. It is designed for remote operation and has primarily been applied to the inspection of nuclear reactor steam generator tubes. The ultrasonic measurements are based on the immersion pulse-echo and/or pitch-catch techniques. Details are given of the main system components - the ultrasonic probes, the calibration/guide tube, the push/puller axial probe driver, the local control unit, and the data acquisition and analysis systems. Illustrations of the application of the system are provided. These include sleeve weld inspection, ID profile/cross section measurement, wall thickness measurement and axial and circumferential crack detection. (UK)

  13. Ultrasonic Resonance Spectroscopy of Composite Rims for Flywheel Rotors

    Science.gov (United States)

    Harmon, Laura M.; Baaklini, George Y.

    2002-01-01

    Flywheel energy storage devices comprising multilayered composite rotor systems are being studied extensively for utilization in the International Space Station. These composite material systems were investigated with a recently developed ultrasonic resonance spectroscopy technique. The ultrasonic system employs a continuous swept-sine waveform and performs a fast Fourier transform (FFT) on the frequency response spectrum. In addition, the system is capable of equalizing the amount of energy at each frequency. Equalization of the frequency spectrum, along with interpretation of the second FFT, aids in the evaluation of the fundamental frequency. The frequency responses from multilayered material samples, with and without known defects, were analyzed to assess the capabilities and limitations of this nondestructive evaluation technique for material characterization and defect detection. Amplitude and frequency changes were studied from ultrasonic responses of thick composite rings and a multiring composite rim. A composite ring varying in thickness was evaluated to investigate the full thickness resonance. The frequency response characteristics from naturally occurring voids in a composite ring were investigated. Ultrasonic responses were compared from regions with and without machined voids in a composite ring and a multiring composite rim. Finally, ultrasonic responses from the multiring composite rim were compared before and after proof spin testing to 63,000 rpm.

  14. Computer-aided ultrasonic inspection of steam turbine rotors

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, K.H.; Weber, M.; Weiss, M. [GEC ALSTHOM Energie GmbH, Nuremberg (Germany)

    1998-12-31

    As the output and economic value of power plants increase, the detection and sizing of the type of flaws liable to occur in the rotors of turbines using ultrasonic methods assumes increasing importance. An ultrasonic inspection carried out at considerable expense is expected to bring to light all safety-relevant flaws and to enable their size to be determined so as to permit a fracture-mechanics analysis to assess the reliability of the rotor under all possible stresses arising in operation with a high degree of accuracy. The advanced computer-aided ultrasonic inspection of steam turbine rotors have improved reliability, accuracy and reproducibility of ultrasonic inspection. Further, there has been an improvement in the resolution of resolvable group indications by applying reconstruction and imagine methods. In general, it is also true for the advanced computer-aided ultrasonic inspection methods that, in the case of flaw-affected forgings, automated data acquisition provides a substantial rationalization and a significant documentation of the results for the fracture mechanics assessment compared to manual inspection. (orig.) 8 refs.

  15. Ultrasonic solvent extraction of organochlorine pesticides from soil

    International Nuclear Information System (INIS)

    Ultrasonic solvent extraction of the organochlorine pesticides (OCP) including α-, β-, γ- and Δ-hexachlorocyclohexane (HCH), heptachlor, aldrin, o,p'-DDE, dieldrin, p,p'-DDE, p,p'-DDT, methoxychlor, mirex from soil is reported. The extraction procedure was optimized with regard to the solvent type, amount of solvent, duration of sonication and number of extraction steps. Determination of pesticides was carried out by gas chromatography (GC) equipped with electron capture detection (ECD). Twice ultrasonic extraction using 25 mL of a mixture of petroleum ether and acetone (1/1 v/v) for 20 min of sonication showed satisfactory extraction efficiency. Recoveries of pesticides from fortified soil samples are over 88% for three different fortification levels between 15 and 200 μg kg-1, and relative standard deviations of the recoveries are generally below 6%. Real soil samples were analyzed for OCP residues by optimized ultrasonic solvent extraction and shake-flask as well as soxhlet extraction technique. Investigated all extraction methods showed comparable extraction efficiencies. Optimized ultrasonic solvent extraction is the most rapid procedure because the use of time in ultrasonic extraction was considerably reduced compared to shake-flask and soxhlet extraction

  16. Risk assessment of turbine rotor failure using probabilistic ultrasonic non-destructive evaluations

    International Nuclear Information System (INIS)

    The study presents a method and application of risk assessment methodology for turbine rotor fatigue failure using probabilistic ultrasonic nondestructive evaluations. A rigorous probabilistic modeling for ultrasonic flaw sizing is developed by incorporating the model-assisted probability of detection, and the probability density function (PDF) of the actual flaw size is derived. Two general scenarios, namely the ultrasonic inspection with an identified flaw indication and the ultrasonic inspection without flaw indication, are considered in the derivation. To perform estimations for fatigue reliability and remaining useful life, uncertainties from ultrasonic flaw sizing and fatigue model parameters are systematically included and quantified. The model parameter PDF is estimated using Bayesian parameter estimation and actual fatigue testing data. The overall method is demonstrated using a realistic application of steam turbine rotor, and the risk analysis under given safety criteria is provided to support maintenance planning

  17. Risk assessment of turbine rotor failure using probabilistic ultrasonic non-destructive evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Guan, Xuefei; Zhang, Jingdan; Zhou, S. Kevin [Siemens Corporation, Corporate Technology, 755 College Rd. E., Princeton NJ 08540 (United States); Rasselkorde, El Mahjoub; Abbasi, Waheed A. [Siemens Energy Inc., 841 Old Frankstown Road, Pittsburgh PA 15239 (United States)

    2014-02-18

    The study presents a method and application of risk assessment methodology for turbine rotor fatigue failure using probabilistic ultrasonic nondestructive evaluations. A rigorous probabilistic modeling for ultrasonic flaw sizing is developed by incorporating the model-assisted probability of detection, and the probability density function (PDF) of the actual flaw size is derived. Two general scenarios, namely the ultrasonic inspection with an identified flaw indication and the ultrasonic inspection without flaw indication, are considered in the derivation. To perform estimations for fatigue reliability and remaining useful life, uncertainties from ultrasonic flaw sizing and fatigue model parameters are systematically included and quantified. The model parameter PDF is estimated using Bayesian parameter estimation and actual fatigue testing data. The overall method is demonstrated using a realistic application of steam turbine rotor, and the risk analysis under given safety criteria is provided to support maintenance planning.

  18. Ultrasonic extensometer measures bolt preload

    Science.gov (United States)

    Daniels, C. M., Jr.

    1978-01-01

    Extensometer using ultrasonic pulse reflections to measure elongations in tightened belts and studs is much more accurate than conventional torque wrenches in application of specified preload to bolts and other threaded fasteners.

  19. Ultrasonically detectable cerebellar haemorrhage in preterm infants.

    LENUS (Irish Health Repository)

    McCarthy, Lisa Kenyon

    2011-07-01

    To determine the frequency and pattern of cerebellar haemorrhage (CBH) on routine cranial ultrasound (cUS) imaging in infants of ≤32 weeks gestation, and to investigate how extremely preterm infants with CBH differ from those with severe intraventricular haemorrhage (IVH).

  20. Detecting gas leaks by ultrasonic emission

    DEFF Research Database (Denmark)

    Rasmussen, Karsten Bo; Henriksen, Eigil

    1997-01-01

    for estimation of the attenuation of sound during free field propagation outdoors has been developed and used for simulations. A number of curves of sound attenuation under varying temperature and humitidy conditions are shown. A crude overall estimate is provided.Computer simulations of the influence...... of the ground reflection on the received sound level have been carried out. These simulations have been carried out for the case of no wind and for one downwind and one upwind example. One of the conclusions is that the receiver should be located several meters over the ground in order to reduce the influence...

  1. Tools for ultrasonic hot embossing

    OpenAIRE

    Liao, Sijie

    2016-01-01

    Ultrasonic hot embossing is an emerging technology enabling molding of thermo-plastic polymers in seconds. A stack of polymer foils is heated by the friction between the foils and protruding microstructures on a tool when ultrasonic vibrations are generated by a sonotrode. The polymer is molten and adapts to the shape of the microstructures on the tool. Thus, a micro structure is generated in much shorter time than by injection molding or hot embossing. The objective of this work was investig...

  2. Ultrasonic Evaluation of Well Integrity

    OpenAIRE

    Hoel, Kristian

    2014-01-01

    This thesis presents the acoustic theory behind current ultrasonic cement evaluation tools. The UltraSonic Imager tool's pulse echo technique and the new Isolation Scanner tool's pitch-catch leaky lamb wave measuring technique is explained. A laboratory experiment is conducted on a steel casing set-up (BeCaLoS) designed by SINTEF Petroleum Research to test, and highlight weaknesses of these measuring techniques. Both evaluation methods are successfully performed under four differen...

  3. Application of ultrasonic phased array technique for inspection of stud bolts in nuclear reactor vessel

    International Nuclear Information System (INIS)

    The stud bolt is one of crucial parts for safety of reactor vessels in nuclear power plants. Cracks initiation and propagation were reported in stud bolts using closure of reactor vessel and head. Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure and radioactive leakage from nuclear reactor. In conventional ultrasonic testing for inspection of stud bolts, crack was detected by using shadow effect. It take too much time to inspect stud bolt by using conventional ultrasonic technique. In addition, there were numerous spurious signal reflected from every thread. In this study, the advanced ultrasonic phased array technique was introduced for inspect stud bolts. The phased array technique provide fast inspection and high detectability of defects. There are sector scanning and linear scanning method in phased array technique, and these scanning methods were applied to inspect stud bolt and detectability was investigated.

  4. 油气输送埋弧焊接钢管超声波自动探伤系统的研制与应用%Development and Application of Ultrasonic Automatic Flaw Detection System for Oil and Gas Pipeline Submerged Arc Welded Steel Pipe

    Institute of Scientific and Technical Information of China (English)

    常少文; 吕育栋; 曹华勇; 田岩平; 刘常庆; 韩玉朝; 孙志敏

    2012-01-01

    分析了油气输送埋弧痒接钢管超声波自动探伤系统的组成结构、检测原理、实施方案以及应用状况。该系统采用单元化和模块化结构设计,可任意组合成探伤通道数为1~N的数字化多通道超声波自动探伤系统。配合探伤操作程序,可做到对复杂缺陷回波的准确评价和严格筛选,有效地避免了系统的误报警,实现了缺陷的自动判别、自动报警、自动存储和缺陷波形动态回放,提高了超声波自动探伤检测的准确性和可靠性,误判率〈2%,漏检率为0。%The structure, inspection theory and construction scheme of an ultrasonic automatm flaw ctetecuon system for oil and gas pipeline submerged arc welded steel pipe, together with its application, are introduced. It uses the modular structure and can be any combination of 1 to N channels of a multi-channel digital ultrasonic automatic flaw detection systerrL With the careful program of flaw detection operation, it can evaluate correctly and select strictly for complex flaw echo, and its error in alarm can be effectively avoided. The review of flaw echo waveform overcomes insufficiency of flaw category nondescript in ultrasonic automatic inspection, and achieves misinformation rate smaller than 2%, fail to report rate to 0.

  5. NON DESTRUCTIVE EVALUATION OF COMPOSITE MATERIALS USING ULTRASONIC SPECTROSCOPY

    OpenAIRE

    Ourak, M.; Nongaillard, B.; Rouvaen, J.; Imouloudene, N.

    1990-01-01

    The non destructive evaluation of the carbon epoxy composite materials (often used in aeronautics) is a difficult matter. The classical control methods prove unsatisfactory for the detection of distributed defects (like delaminations and porosities), which affect severely the mechanical properties of composite parts. Ultrasonic echography (A scan mode) allows for the detection of some kinds of delaminations, but the interpretation of the echographic signal remains difficult in the case of por...

  6. Noncontact ultrasonic thickness measurements of thin aluminium sheet

    International Nuclear Information System (INIS)

    A method has been described for the noncontact ultrasonic thickness measurements of thin aluminium sheets, using a Q-switched ruby laser generation concentric with an annular electro-magnetic acoustic transducer (EMAT) detection to imitate pulse-echo system. The detected waveforms were analyzed with the cut-off frequences of the higher order lamb modes. The results show in a good egreement with micrometer measurements within 2% discrepancy. (authors). 22 refs, 6 figs

  7. Flexible ultrasonic transducers for structural health monitoring

    International Nuclear Information System (INIS)

    Flexible ultrasonic transducers (FUTs) which have on-site installation capability are presented for non-destructive evaluation (NDE) and structural health monitoring (SHM) purposes. These FUTs typically consist of a 70 μm thick piezoelectric lead-zirconate-titanate (PZT) composite (PZT-c) coated by a sol-gel spray technique on a 75 μm thick titanium (Ti) membrane. Such an FUT was glued onto a steel pipe of 101 mm in diameter and 4.5 mm in wall thickness and heated at up to 200oC with the glue serving as a high temperature ultrasonic couplant. The pipe thickness measurement accuracy at 200oC is estimated to be 13 μm. FUTs were also glued onto the end edge of a 2 mm thick aluminum (Al) plate to generate and receive predominantly shear-horizontal (SH) plate acoustic waves (PAWs) to detect simulated line defects at temperatures of up to 100oC. FUTs, glued onto a graphite/epoxy (Gr/Ep) composite plate, were also used for the detection of an artificial disbond. An induction type non-contact method for the evaluation of Al plates and Gr/Ep composites using FUTs is also demonstrated. (author)

  8. Unconventional field and angle dependences of the Shubnikov-de Haas oscillations spectra in the quasi two-dimensional organic superconductor (BEDO-TTF)2ReO4H2O

    International Nuclear Information System (INIS)

    We report on the inter-layer oscillatory conductance of the two-dimensional organic superconductor (BEDO-TTF)2ReO4H2O measured in static and pulsed magnetic fields of up to 15 and 52 T, respectively. In agreement with previous in-plane studies, two Shubnikov-de Haas oscillation series linked to the two electron and the hole orbits are observed. The influence of the magnitude and orientation of the magnetic field with respect to the conducting plane is studied in the framework of the conventional two- and three-dimensional Lifshits-Kosevich (LK) model. Deviations of the data from this model are observed in low fields strongly tilted with respect to the normal to the conducting plane. In this latter case, the observed behaviour is consistent with an unexplained lowering of the cyclotron effective mass. At high magnetic field, the oscillatory data could have been compatible with the occurrence of a magnetic breakdown orbit built from the hole and electron orbits. However, the increase of the cyclotron effective mass, linked to the electron orbits, as the magnetic field increases above ∝12 T is consistent with a field-induced phase transition. In the lower field range, where the conventional LK model holds, the analysis of the angle dependence of the oscillations amplitude suggests significant renormalisation of the effective Lande factor. (orig.)

  9. Model-based inversion for the characterization of crack-like defects detected by ultrasound in a cladded component; Etude d'une methode d'inversion basee sur la simulation pour la caracterisation de fissures detectees par ultrasons dans un composant revetu

    Energy Technology Data Exchange (ETDEWEB)

    Haiat, G

    2004-03-01

    This work deals with the inversion of ultrasonic data. The industrial context of the study in the non destructive evaluation of the internal walls of French reactor pressure vessels. Those inspections aim at detecting and characterizing cracks. Ultrasonic data correspond to echographic responses obtained with a transducer acting in pulse echo mode. Cracks are detected by crack tip diffraction effect. The analysis of measured data can become difficult because of the presence of a cladding, which surface is irregular. Moreover, its constituting material differs from the one of the reactor vessel. A model-based inverse method uses simulation of propagation and of diffraction of ultrasound taking into account the irregular properties of the cladding surface, as well as the heterogeneous nature of the component. The method developed was implemented and tested on a set of representative cases. Its performances were evaluated by the analysis of experimental results. The precision obtained in the laboratory on experimental cases treated is conform with industrial expectations motivating this study. (author)

  10. Ultrasonic measurements and technologies

    CERN Document Server

    Kočiš, Štefan

    1996-01-01

    An impulse for writing this book has originated from the effort to sum­ marize and publicise the acquired results of a research team at the De­ partment of Automation of the Faculty of Electrical Engineering and In­ formatics, Slovak Technical University in Bratislava. The research team has been involved for a long time with control problems for machine production mechanisms and, in recent (approximately 15) years, its effort was aimed mostly at the control of electrical servosystems of robots. Within this scope, the members of the authors' staff solved the State Re­ search Task Ultrasonic sensing of the position of a robot hand, which was coordinated by the Institute of Technical Cybernetics of the Slovak Academy of Sciences in Bratislava. The problem was solved in a complex way, i.e. from a conceptual de­ sign of the measurement, through the measurement and evaluation sys­ tem, up to connection to the control system of a robot. Compensation of the atmospheric influence on the precision of measurement,...

  11. [Ultrasonics in endodontics: mechanism of action].

    Science.gov (United States)

    Pacheco Plaza, M C; Kessler Nieto, F; Orts Rodríguez, M T; Ruiz de Temiño Malo, P

    1989-01-01

    The present study, first of three dwelling with ultrasonics in endodontic therapy, is a review of the literature about mechanisms involved and appliance of some of the sonic and ultrasonic system. PMID:2700391

  12. A study on Pc- based ultrasonic testing system using intelligent ultrasonic flaw classification software

    International Nuclear Information System (INIS)

    For convenient application of ultrasonic pattern recognition approaches in practical field inspection of weldments, we have developed an intelligent ultrasonic flaw classification system by the novel combination of two ingredients; 1) a PC-based ultrasonic testing system, and 2) an intelligent ultrasonic flaw classification software with an invariant ultrasonic pattern recognition algorithm. Here, key aspects of this intelligent system are addressed including the Pc-based ultrasonic testing system, enhancement of the performance by use of newly proposed ultrasonic features, and feature selection.

  13. Generation of tone burst laser ultrasonic waves and its acoustic nonlinearity

    International Nuclear Information System (INIS)

    Optical system for generating tone burst ultrasonic wave is introduced and the actual waveform is demonstrated. 4 high power pulse lasers were used for excitation and the stabilized Michelson laser interferometer was used as detection. On the other hand, we tried to investigate the nonlinear acoustic effect of the generated tone burst laser ultrasonic wave. In thermo-elastic region, the nonlinearity did not appear because the absolute amplitude of ultrasonic wave was so small less than 0.5 nm. Whereas, in ablation region, fairly strong nonlinearity appeared because the absolute amplitude of receiving signal was quite large up to about 2 nm.

  14. Automatic ultrasonic testing and the LOFT in-service inspection program

    International Nuclear Information System (INIS)

    An automatic ultrasonic testing system has been developed which significantly improves the flaw indication detection and characterization capability over the capability of conventional volumetric examination techniques. The system utilizes an accurately located ultrasonic sensor to generate the examination data. A small computer performs and integrates control and data input/output functions. Computer software has been developed to provide a rigorous method for data analysis and ultrasonic image interpretation. The system has been used as part of an in-service inspection program to examine welds in thich austenitic stainless steel pipes in a small experimental nuclear reactor

  15. Development of ultrasonic transducer with high resistance to temperature and radiation

    International Nuclear Information System (INIS)

    Ordinary ultrasonic transducers cannot be used to inspect equipment at a high radiation facility such as vitrification facility or fusion reactor. IHI has developed an ultrasonic transducer with high resistance to temperature and radiation and confirmed the radiation tolerance up to 10 MGy. IHI has applied the ultrasonic transducer to lid welding inspection of vitrification packages, and obtained good results such as clear detection of an artificial 0.5 mm diameter hole penetrating the stainless steel lid welding. This technology could be applied to ISI (In-Service Inspection) of nuclear plants, ensuring safe operation of nuclear plants. (author)

  16. Determination of gas pressure in voids in epoxy casting using an ultrasonic measuring technique

    DEFF Research Database (Denmark)

    Larsen, Esben; Petersen, C. Bak; Henriksen, Mogens

    1990-01-01

    Results of measurements performed on a large open void, where pressure can be controlled from the outside, are compared to the theory of ultrasound transmission. The results verify the theory that the attenuation of transmitted ultrasonic signals through a void depends on the gas pressure inside...... the void. The results are based on the use of time delay spectrometry. This method gives a sufficiently high signal-to-noise ratio for detecting the transmitted part of the ultrasonic signal which has travelled through the void. Because of differences in the density and velocity of ultrasonic signals...... for the materials involved, that part of the signal is dependent on the pressure inside the void...

  17. Performance demonstration for an automated ultrasonic testing system for piping welds

    International Nuclear Information System (INIS)

    This paper addresses the implementation of an automated ultrasonic testing (AUT) system qualification by performance demonstration (PD) as imposed by the ASME Boiler and Pressure Vessel Code Section XI. To improve the reliability of the ultrasonic testing results for nuclear power plant (NPP) components, almost all engineering codes related to NPP inspection require the ultrasonic inspection systems to be qualified by passing a PD examination. In this study, an AUT system developed to inspect pipe welding parts in NPPs is introduced. To acquire a Korean Performance Demonstration (KPD) qualification, the developed system had a KPD. System obtained the qualification for flaw detection, length, and depth sizing from KPD. (author)

  18. Analysis of partial discharge Ultrasonic wave characteristic on typical Defects in GIS

    Directory of Open Access Journals (Sweden)

    Yang Jing Gang

    2016-01-01

    Full Text Available For analyzing partial discharge ultrasonic wave characteristic on typical defects in SF6 gas insulation switchgear (GIS, a 110 kV GIS was taken as an object to design and simulate the typical partial discharge models in GIS. There are point electrode model on bus and cavity of GIS, floating electrode model, air interstice model in insulator, metal particle and iron core electromagnetic shock models. PD signals on different defects were thus detected with the ultrasonic method. The experimental results indicated that the ultrasonic signals of different defects showed different characteristics in waveform, amplitude and phase resolved partial discharge chart, which is helpful in PD pattern recognition for GIS.

  19. Inspection of tubing defects with ultrasonic guided waves

    International Nuclear Information System (INIS)

    The purpose of this study is to show the utility of ultrasonic guided waves in 439 stainless steel heat exchanger and Inconel steam generator tubing inspection. Phase velocity and group velocity dispersion curves for the longitudinal and flexural modes of a sample Inconel steam generator tube were presented. In experimental studies, ultrasonic guided wave applications were demonstrated for man made flaws. For the detection of EDM wears under a tube support plate in the heater exchanger tubing, a bore probe generated axisymmetric longitudinal guided wave modes in the tubing. For the detection and sizing of circumferential Laser notches in Inconel steam generator tubes, a variable angle beam transducer set up was used. Excellent detection results were demonstrated for EDM wears and Laser Notches with various modes and L(0,1) modes, respectively. Circumferential sizing of Laser notches was achieved with L(0,1) mode at 3.5 MHz.

  20. Contribution of dynamic focusing to ultrasonic defect characterization

    International Nuclear Information System (INIS)

    Non destructive testing of vessels of pressurized water reactors uses ultrasonic focused transducers, with spherically shaped emitting surface or requiring an acoustic lens. But a mechanically focused transducer has to be used for a given inspection zone and for a fixed control configuration. The aim of this thesis is to improve ultrasonic defect characterization using adaptive dynamic focusing. Such a technique makes use of a ultrasonic defect characterization using adaptive dynamic focusing. Such a technique makes use of an ultrasonic transducer split into an array of individually controlled elements, allowing to apply delay and amplitude laws, calculated from modeling or experimentally deduced. Acoustical characteristics of the ultrasonic beam in the inspected specimen this can be electronically controlled; refraction angle, depth focusing, beam width. We briefly describe in the first chapter a theoretical modeling of the ultrasonic field radiated through a fluid/solid interface, extended to phase array transducers. This model is based on the integral formulation of Rayleigh, modified to take into account transmission through a fluid/solid (homogeneous and isotropic), of planar or cylindrical shape. In the second chapter an experimental study of this technique, with delay and amplitude laws given from the model, is presented, showing the efficiency of this method to adjust the acoustic performances. In he third chapter, experimental delay laws, extracted from the time distribution of signals received by the array (issued from a preliminary detected reflector), are used to provide an optimal imaging of the defect. This self-focusing procedure shows to adapt to a defect without using theoretical delays. The last chapter is dedicated to different applications devoted to improved defect characterization. The first application uses amplitude distribution received by the array, pointing out geometric characteristics of the reflector, while the second application

  1. A new deconvolution method applied to ultrasonic images

    International Nuclear Information System (INIS)

    This dissertation presents the development of a new method for restoration of ultrasonic signals. Our goal is to remove the perturbations induced by the ultrasonic probe and to help to characterize the defects due to a strong local discontinuity of the acoustic impedance. The point of view adopted consists in taking into account the physical properties in the signal processing to develop an algorithm which gives good results even on experimental data. The received ultrasonic signal is modeled as a convolution between a function that represents the waveform emitted by the transducer and a function that is abusively called the 'defect impulse response'. It is established that, in numerous cases, the ultrasonic signal can be expressed as a sum of weighted, phase-shifted replicas of a reference signal. Deconvolution is an ill-posed problem. A priori information must be taken into account to solve the problem. The a priori information translates the physical properties of the ultrasonic signals. The defect impulse response is modeled as a Double-Bernoulli-Gaussian sequence. Deconvolution becomes the problem of detection of the optimal Bernoulli sequence and estimation of the associated complex amplitudes. Optimal parameters of the sequence are those which maximize a likelihood function. We develop a new estimation procedure based on an optimization process. An adapted initialization procedure and an iterative algorithm enables to quickly process a huge number of data. Many experimental ultrasonic data that reflect usual control configurations have been processed and the results demonstrate the robustness of the method. Our algorithm enables not only to remove the waveform emitted by the transducer but also to estimate the phase. This parameter is useful for defect characterization. At last the algorithm makes easier data interpretation by concentrating information. So automatic characterization should be possible in the future. (author)

  2. Laser-Ultrasonic Testing and its Applications to Nuclear Reactor Internals

    Science.gov (United States)

    Ochiai, M.; Miura, T.; Yamamoto, S.

    2008-02-01

    A new nondestructive testing technique for surface-breaking microcracks in nuclear reactor components based on laser-ultrasonics is developed. Surface acoustic wave generated by Q-switched Nd:YAG laser and detected by frequency-stabilized long pulse laser coupled with confocal Fabry-Perot interferometer is used to detect and size the cracks. A frequency-domain signal processing is developed to realize accurate sizing capability. The laser-ultrasonic testing allows the detection of surface-breaking microcrack having a depth of less than 0.1 mm, and the measurement of their depth with an accuracy of 0.2 mm when the depth exceeds 0.5 mm including stress corrosion cracking. The laser-ultrasonic testing system combined with laser peening system, which is another laser-based maintenance technology to improve surface stress, for inner surface of small diameter tube is developed. The generation laser in the laser-ultrasonic testing system can be identical to the laser source of the laser peening. As an example operation of the system, the system firstly works as the laser-ultrasonic testing mode and tests the inner surface of the tube. If no cracks are detected, the system then changes its work mode to the laser peening and improves surface stress to prevent crack initiation. The first nuclear industrial application of the laser-ultrasonic testing system combined with the laser peening was completed in Japanese nuclear power plant in December 2004.

  3. Study of ultrasonic thermometry based on ultrasonic time-of-flight measurement

    Directory of Open Access Journals (Sweden)

    Ruixi Jia

    2016-03-01

    Full Text Available Ultrasonic thermometry is a kind of acoustic pyrometry and it has been evolving as a new temperature measurement technology for various environment. However, the accurate measurement of the ultrasonic time-of-flight is the key for ultrasonic thermometry. In this paper, we study the ultrasonic thermometry technique based on ultrasonic time-of-flight measurement with a pair of ultrasonic transducers for transmitting and receiving signal. The ultrasonic transducers are installed in a single path which ultrasonic travels. In order to validate the performance of ultrasonic thermometry, we make a contrast about the absolute error between the measured temperature value and the practical one. With and without heater source, the experimental results indicate ultrasonic thermometry has high precision of temperature measurement.

  4. Study of ultrasonic thermometry based on ultrasonic time-of-flight measurement

    Science.gov (United States)

    Jia, Ruixi; Xiong, Qingyu; Wang, Lijie; Wang, Kai; Shen, Xuehua; Liang, Shan; Shi, Xin

    2016-03-01

    Ultrasonic thermometry is a kind of acoustic pyrometry and it has been evolving as a new temperature measurement technology for various environment. However, the accurate measurement of the ultrasonic time-of-flight is the key for ultrasonic thermometry. In this paper, we study the ultrasonic thermometry technique based on ultrasonic time-of-flight measurement with a pair of ultrasonic transducers for transmitting and receiving signal. The ultrasonic transducers are installed in a single path which ultrasonic travels. In order to validate the performance of ultrasonic thermometry, we make a contrast about the absolute error between the measured temperature value and the practical one. With and without heater source, the experimental results indicate ultrasonic thermometry has high precision of temperature measurement.

  5. Ultrasonic stir welding process and apparatus

    Science.gov (United States)

    Ding, R. Jeffrey (Inventor)

    2009-01-01

    An ultrasonic stir welding device provides a method and apparatus for elevating the temperature of a work piece utilizing at least one ultrasonic heater. Instead of relying on a rotating shoulder to provide heat to a workpiece an ultrasonic heater is utilized to provide ultrasonic energy to the workpiece. A rotating pin driven by a motor assembly performs the weld on the workpiece. A handheld version can be constructed as well as a fixedly mounted embodiment.

  6. Estimating adipose tissue in the chest wall using ultrasonic and alternate 40K and biometric measurements

    International Nuclear Information System (INIS)

    The percentage of adipose (fat) tissue in the chest wall must be known to accurately measure Pu in the human lung. Correction factors of 100% or more in X-ray detection efficiency are common in a normal population of individuals of differing body composition and have been determined in the past by means of elaborate and costly ultrasonic measurements of the subject's chest. Methods using simple 40K and biometric measurement techniques have been investigated to determine the adipose content in the human chest wall. These methods compare favorably with ultrasonic measurements and allow laboratories not possessing ultrasonic equipment to make appropriate corrections for x-ray detection efficiency. These methods predict adipose content to within 15% of the absolute ultrasonic value. (author)

  7. Numeric ultrasonic image processing method: application to non-destructive testing of stainless austenitic steel welds

    International Nuclear Information System (INIS)

    A bibliographic research on the means used to improve the ultrasonic inspection of heterogeneous materials such as stainless austenitic steel welds has shown, taking into account the first analysis, a signal assembly in the form of an image (space, time) which carries an original solution to fault detection in highly noisy environments. A numeric grey-level ultrasonic image processing detection method is proposed based on the research of a certain determinism, in the way which the ultrasonic image evolves in space and time in the presence of a defect: the first criterion studies the horizontal stability of the gradients in the image and the second takes into account the time-transient nature of the defect echo. A very important rise in the signal-to-noise ratio obtained in welding inspections evidencing defects (real and artificial) is shown with the help of a computerized ultrasonic image processing/management system, developed for this application

  8. High temperature pressure coupled ultrasonic waveguide

    International Nuclear Information System (INIS)

    A pressure coupled ultrasonic waveguide is provided to which one end may be attached a transducer and at the other end a high temperature material for continuous ultrasonic testing of the material. The ultrasonic signal is coupled from the waveguide into the material through a thin, dry copper foil

  9. Ultrasonic ash/pyrite liberation

    Energy Technology Data Exchange (ETDEWEB)

    Yungman, B.A.; Buban, K.S.; Stotts, W.F.

    1990-06-01

    The objective of this project was to develop a coal preparation concept which employed ultrasonics to precondition coal prior to conventional or advanced physical beneficiation processes such that ash and pyrite separation were enhanced with improved combustible recovery. Research activities involved a series of experiments that subjected three different test coals, Illinois No. 6, Pittsburgh No. 8, and Upper Freeport, ground to three different size fractions (28 mesh [times] 0, 200 mesh [times] 0, and 325 mesh [times] 0), to a fixed (20 kHz) frequency ultrasonic signal prior to processing by conventional and microbubble flotation. The samples were also processed by conventional and microbubble flotation without ultrasonic pretreatment to establish baseline conditions. Product ash, sulfur and combustible recovery data were determined for both beneficiation processes.

  10. Ultrasonic testing and sensors. Lectures

    International Nuclear Information System (INIS)

    Progress in ultrasonic testing is based for many applications on the now available electro-acoustic transducers and on their adaptation to the different requirements. Experience on the use of new and often unusual transducer concepts rarely spreads beyond the area of the directly interested users. The consideration of the test head for ultrasonic testing as an electro-acoustic sensor contains an intentional generalisation by which an exchange of knowledge and experience from very different fields is to be started. In 20 lectures, the seminar introduced sensor concepts and applications from different areas of application of ultrasonic pulse echo technique and sound emission, therefore gave a survey of new developments and provide the stimulus for solving special problems. (orig./HP)

  11. Lamb Wave Helical Ultrasonic Tomography

    Science.gov (United States)

    Leonard, K. R.; Hinders, M. K.

    2004-02-01

    Ultrasonic guided waves have been used for a wide variety of ultrasonic inspection techniques. We describe here a new variation called helical ultrasound tomography (HUT). This new technique, among other things, has direct application to advanced pipe inspection. HUT uses guided ultrasonic waves along with an adaptation of the tomographic reconstruction algorithms developed by seismologists for what they call "cross borehole" tomography. In HUT, the Lamb-like guided waves travel in various helical crisscross paths between two parallel circumferential transducer arrays instead of the planar crisscross seismic paths between two boreholes. Although the measurement itself is fairly complicated, the output of the tomographic reconstruction is a readily interpretable map of a quantity of interest such as pipe wall thickness. We demonstrate the feasibility of the HUT technique via laboratory scans on steel pipe segments into which controlled thinnings have been introduced.

  12. Nickel Based Coatings Containing TiN Nanoparticles Prepared by Ultrasonic-Electrodeposition Technology

    OpenAIRE

    Yong Wang; Fafeng Xia; Chao Liu; Hongyan Yin

    2013-01-01

    In order to enhance the surface properties of steel substrates, nano Ni-TiN composite coatings were prepared using ultrasonic-electrodeposition technology in this study. The effects of ultrasonic on composite coatings were studied. The X-Ray Diffraction (XRD) study had been utilized to detect the crystalline and amorphous characteristics of Ni-TiN composite coatings. The surface morphology and metallurgical structure of composite coatings were observed with Scanning Electron Microscope (SEM) ...

  13. Final results of double-shell tank 241-AN-105 ultrasonic inspection

    Energy Technology Data Exchange (ETDEWEB)

    JENSEN, C.E.

    1999-08-23

    This document presents the results and documentation of the nondestructive ultrasonic examination of tank 241-AN-105. A tank inspection supplier was retained to provide and use an ultrasonic examination system (equipment, procedures, and inspectors) to scan a limited area of double-shell tank 241-AN-105 primary tank wall primary knuckle, and secondary tank bottom. The inspection found some indication of general and local wall thinning with no cracks detected.

  14. Estimating adipose tissue in the chest wall using ultrasonic and alternate 40K and biometric measurements

    International Nuclear Information System (INIS)

    The percentage of adipose (fat) tissue in the chest wall must be known to accurately measure Pu in the human lung. Correction factors of 100% or more in x-ray detection efficiency are common. Methods using simple 40K and biometric measurement techniques were investigated to determine the adipose content in the human chest wall. These methods predict adipose content to within 15% of the absolute ultrasonic value. These new methods are discussed and compared with conventional ultrasonic measurement techniques

  15. Laser ultrasonics and guided waves for the thickness estimation of thin layers

    OpenAIRE

    Lefèvre, Fabien; Jenot, Frédéric; Ouaftouh, Mohammadi; Duquennoy, Marc; Ourak, Mohamed

    2010-01-01

    The dispersion of guided waves has been probed to estimate the thickness of a thin gold layer deposited on a two inches silicon wafer. Ultrasonic waves were generated and detected in a non-destructive and non-contact way using a laser ultrasonic setup. The guided waves dispersion curves were experimentally obtained with a two-dimensional Fourier transform, revealing the propagation of several modes. The development and the study of an analytical model allowed the determination of the most sen...

  16. Final results of double-shell tank 241-AN-105 ultrasonic inspection

    International Nuclear Information System (INIS)

    This document presents the results and documentation of the nondestructive ultrasonic examination of tank 241-AN-105. A tank inspection supplier was retained to provide and use an ultrasonic examination system (equipment, procedures, and inspectors) to scan a limited area of double-shell tank 241-AN-105 primary tank wall primary knuckle, and secondary tank bottom. The inspection found some indication of general and local wall thinning with no cracks detected

  17. Final results of double-shell tank 241-AY-102 ultrasonic inspection

    International Nuclear Information System (INIS)

    This document presents the results and documentation of the nondestructive ultrasonic examination of tank 241-AY-102. A tank inspection supplier was retained to provide and use an ultrasonic examination system (equipment, procedures, and inspectors) to scan a limited area of double-shell tank 241-AY-102 primary tank wall and welds. The inspection found some indication of insignificant general and local wall thinning with no cracks detected

  18. Ultrasonic monitoring of material processing using clad buffer rod sensors

    Science.gov (United States)

    Ramos Franca, Demartonne

    Ultrasonic sensors and techniques are developed for in-line monitoring of polymer extrusion, cleanliness of molten metals and liquid flow speed at elevated temperature. Pulse-echo mode is used for the first two processes, while the through-transmission mode is applied in the third one. The ultrasonic probe consists of high performance clad buffer rods with different dimensions to thermally isolate the commercial ultrasonic transducer from materials at high temperature. The clad buffer rods are made of steel, polymer and ceramic. Steel clad buffer rods are introduced for in-line monitoring of polymer extrusion processes. Owing to its superior performance in pulse-echo mode, for the first time such a probe is installed and performs ultrasonic monitoring in the die of a co-extrusion machine and in the barrel section of a twin-screw extruder. It can reveal a variety of information relevant to process parameters, such as polymer layer thickness, interface location and adhesion quality, stability, or polymer composition change. For the ultrasonic monitoring of polymer processes, probes with acoustic impedance that matches that of the processed polymer may offer certain advantages such as quantitative viscoelastic evaluation; thus high temperature polymer clad buffer rods, in particular PEEK, are developed. It is demonstrated that this new probe exhibits unique advantages for in-line monitoring of the cure of epoxies and polymer extrusion process. Long steel clad buffer rods with a spherical focus lens machined at the probing end are proposed for cleanliness evaluation of molten metals. The potential of this focusing probe is demonstrated by means of high-resolution imaging and particles detection in molten zinc at temperatures higher than 600°C, using a single probe operated at pulse-echo mode. A contrapropagating ultrasonic flowmeter employing steel clad buffer rods is devised to operate at high temperature. It is demonstrated that these rods guide ultrasonic signals

  19. Dependences of ultrasonic properties on the propagation angle with respect to the trabecular alignment in trabecular bone

    International Nuclear Information System (INIS)

    The present study aims to investigate the dependences of ultrasonic properties on the propagation angle with respect to the trabecular alignment in 12 bovine femoral trabecular bone samples. The phase velocity and the attenuation coefficient of the fast wave measured at 0.5 MHz were found to decrease significantly with increasing angle and had their maximum values at 0 .deg. , i.e., for wave propagation in a direction parallel to the predominant trabecular alignment. The present study applied the angle-dependent Biot model by introducing anisotropy into the Biot model through the angle-dependent Young's, bulk, and shear moduli of the skeletal frame for trabecular bone to predict the measurements. Good agreement between the measurements and the prediction of the fast wave velocity suggests that the anisotropic fast wave velocity as a function of the propagation angle is mainly due to the variation in the elastic moduli of the skeletal frame with respect to the trabecular alignment.

  20. On line ultrasonic integrated backscatter

    International Nuclear Information System (INIS)

    A new equipment for on-line evaluation of index based on two-dimensional integrated backscatter from ultrasonic images is described. The new equipment is fully integrated into a B-mode ultrasonic apparatus which provides a simultaneous display of conventional information together with parameters of tissue characterization. The system has been tested with a backscattering model of microbubbles in polysaccharide solution, characterized by a physiological exponential time decay. An exponential fitting to the experimental data was performed which yielded r=0.95

  1. Very high temperature ultrasonic thermometer

    International Nuclear Information System (INIS)

    An ultrasonic thermometer comprises an electric pulse transducer head, a pulse transmission line, a notched sensor wire attached to and extending along the axis of said transmission line and a sheath enclosing the transmission line and the sensor wire, a portion of the interior face of the sheath being covered by a stuffing material along at least the length of the notched part of the sensor wire, such that contact between the sensor wire and the stuffing material does not substantially give rise to reflection of an ultrasonic pulse at the point of contact. (author)

  2. Flow measurement by ultrasonic method

    International Nuclear Information System (INIS)

    An Ultrasonic Flow Meter (USFM) wasdeveloped to measure flow velocity of high temperature fluid in a pipe. To protect ultrasonic transducers from high temperature, guide rods were used. From the study on mechanical structure and acoustic property, the guide rod and the electronic circuit were improved to have capabilities of temperature compensation, quick response, high accuracy and not to be easily disturbed by bubbles contained in the fluid flow. Using a water flow loop, the test results proved the accuracy of +-1.0 percent and response time of 10 m sec

  3. Ultrasonic large aperture imaging system

    International Nuclear Information System (INIS)

    A new ultrasonic large aperture imaging technique is described. This device combines a focussed transducer as a transmitter, producing a small ultrasonic beam, with N transducers as receivers. We show that is possible to considerably reduce the number of receivers if, on the one hand, we limit the reconstitution process to the emitter beam area and, on the other hand, we ensure that the artefacts, caused by the spatial sampling of the reception, are outside this area. Under these conditions, the result is a high resolution image which does not require large reconstitution processing times. Theoretical and experimental results are given

  4. Dental hard tissue characterization using laser-based ultrasonics

    Science.gov (United States)

    Blodgett, David W.; Massey, Ward L.

    2003-07-01

    Dental health care and research workers require a means of imaging the structures within teeth in vivo. One critical need is the detection of tooth decay in its early stages. If decay can be detected early enough, the process can be monitored and interventional procedures, such as fluoride washes and controlled diet, can be initiated to help re-mineralize the tooth. Currently employed x-ray imaging is limited in its ability to visualize interfaces and incapable of detecting decay at a stage early enough to avoid invasive cavity preparation followed by a restoration. To this end, non-destructive and non-contact in vitro measurements on extracted human molars using laser-based ultrasonics are presented. Broadband ultrasonic waves are excited in the extracted sections by using a pulsed carbon-dioxide (CO2) laser operating in a region of high optical absorption in the dental hard tissues. Optical interferometric detection of the ultrasonic wave surface displacements in accomplished with a path-stabilized Michelson-type interferometer. Results for bulk and surface in-vitro characterization of caries are presented on extracted molars with pre-existing caries.

  5. SmartBall™: Free Swimming Leak Detection System

    OpenAIRE

    ECT Team, Purdue

    2008-01-01

    Leak detection systems measure ultrasonic noise, infrared temperature variances or electrical flux to detect leakage in structures like, pipes, tanks, geo-membrane retaining structures etc. SmartBall® is a free flowing leak detection system developed by Pure Technologies. It consists of a foam ball that has a smaller aluminum ball at its core. This aluminum core houses an ultrasonic device that sends ultrasonic signals and also collects the reflected sound waves.

  6. In situ ultrasonic surface wave assesment of fatigue damage accumulation in AL 6061

    International Nuclear Information System (INIS)

    This work investigated in situ characterization of room temperature fatigue damage in Al6061 material using an ultrasonic surface wave technique. The goal of the work was to show that an in situ surface wave technique would provide valuable information concerning fatigue damage initiation and accumulated process in Al6061 material of aircraft application. Two kinds of plate specimen were made for this study. The specimens were at least 160 mm in length to accommodate the ultrasonic surface wave transducer with 2 or 4 MHz frequency, while the specimen is held in the grips of MTS hydraulic fatigue test machine. Once the transducer were in place, ultrasonic data was recorded by both digital ultrasonic flaw detecter(USD10) and computer before the fatigue tests were started. The fatigue tests were then started and the specimen were cycled to the desired number of cycles and finally to the fracture of specimen. The ultrasonic data were recorded for two kinds of applied stress level with the some stress ratio(R=0.01). It was found clearly that the velocity and attenuation of ultrasonic surface wave were changed due to the number of fatigue cycle as well as the change of applied stress levels. From the results, the applicability of in situ ultrasonic surface wave technique to evaluate successive change of fatigue damage of Al6061 was discussed in more details.

  7. A process optimization study on ultrasonic extraction of paclitaxel from Taxus cuspidata.

    Science.gov (United States)

    Wang, Shujie; Li, Chun; Wang, Hujun; Zhong, Xiangmei; Zhao, Jing; Zhou, Yajun

    2016-04-01

    This study aimed to improve the extraction rate of paclitaxel from Taxus cuspidata in order to determine the most effective combination of ultrasonic extraction and thin-layer chromatography-ultraviolet (TLC-UV) rapid separation method. The study was performed using the Box-Behnken test design to conduct single-factor experiments using ultrasonic extraction of paclitaxel from Taxus cuspidata. The study showed ethanol to be the best extraction solvent. When mixed with dichloromethane (1:1), the ratio of material to liquid was 1:50 when using an ultrasonic time of 1 hr at a power of 200 W. The correction coefficient K for the separation and detection of paclitaxel using the TLC-UV spectrophotometric method was 0.009152. Multifactor experiments determined the effect of the rate of liquid to material (X1), ultrasonic time (X2), and ultrasonic power (X3) on extraction using extraction volume as the dependent variable. Response surface analysis allowed a regression equation to be obtained, with the optimal conditions for extraction when the rate of liquid to material was 53.23 mL/g as an ultrasonic time of 1.11 hr and an ultrasonic power of 207.88 W. Using these parameters, the average amount of extracted paclitaxel was about 130.576 µg/g, which was significantly better than for other extraction methods. PMID:25830908

  8. High-Performance Acousto-Ultrasonic Scan System Being Developed

    Science.gov (United States)

    Roth, Don J.; Martin, Richard E.; Cosgriff, Laura M.; Gyekenyesi, Andrew L.; Kautz, Harold E.

    2003-01-01

    Acousto-ultrasonic (AU) interrogation is a single-sided nondestructive evaluation (NDE) technique employing separated sending and receiving transducers. It is used for assessing the microstructural condition and distributed damage state of the material between the transducers. AU is complementary to more traditional NDE methods, such as ultrasonic cscan, x-ray radiography, and thermographic inspection, which tend to be used primarily for discrete flaw detection. Throughout its history, AU has been used to inspect polymer matrix composites, metal matrix composites, ceramic matrix composites, and even monolithic metallic materials. The development of a high-performance automated AU scan system for characterizing within-sample microstructural and property homogeneity is currently in a prototype stage at NASA. This year, essential AU technology was reviewed. In addition, the basic hardware and software configuration for the scanner was developed, and preliminary results with the system were described. Mechanical and environmental loads applied to composite materials can cause distributed damage (as well as discrete defects) that plays a significant role in the degradation of physical properties. Such damage includes fiber/matrix debonding (interface failure), matrix microcracking, and fiber fracture and buckling. Investigations at the NASA Glenn Research Center have shown that traditional NDE scan inspection methods such as ultrasonic c-scan, x-ray imaging, and thermographic imaging tend to be more suited to discrete defect detection rather than the characterization of accumulated distributed microdamage in composites. Since AU is focused on assessing the distributed microdamage state of the material in between the sending and receiving transducers, it has proven to be quite suitable for assessing the relative composite material state. One major success story at Glenn with AU measurements has been the correlation between the ultrasonic decay rate obtained during AU

  9. Directivity measurements in aluminum using a laser ultrasonics system

    International Nuclear Information System (INIS)

    A laser ultrasonics system was setup to measure the directivity (angular dependence pattern) of the amplitude of ultrasonic waves generated in aluminum samples. A pulsed Nd:YAG laser operating at 1064 nm optical wavelength, with typical pulse width (FWHM) of 8 ns, and energy per pulse of 450 mJ, was used to generate the ultrasound waves in the samples. The laser detection system was a Mach-Zehnder interferometer with typical noise-limited resolution of 0.25 nm (rms), frequency range from 50 kHz to 20 MHz, and measurement range from -75 nm/V to +75 nm/V. Two different optical spot sizes of the Nd:YAG laser were used to generate waves in the ablation regime: one was focused and the other was unfocused. Using the obtained data, the directivity graphics were drawn and compared with the theoretical curves, showing a good agreement. The experiments showed the directivity as a function of the optical spot size. For a point ultrasonic source (or focused optical spot), the directivity shows that the longitudinal waves present considerable amplitude in all directions. For a larger ultrasonic source (or an unfocused optical spot) the directivity shows that the longitudinal waves are generated with the higher amplitudes inside angles around ±100.

  10. Directivity measurements in aluminum using a laser ultrasonics system

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, J M S; Pacheco, G M [Instituto Tecnologico de Aeronautica, Praca Marechal Eduardo Gomes, 50 - Vila das Acacias, Sao Jose dos Campos - SP, 12228-900 (Brazil); Tittmann, B R [Pennsylvania State University, 212 Earth and Engr. Sciences Building, University Park - PA, 16802-6812 (United States); Baba, A, E-mail: sakamoto@ieav.cta.br [Hitachi, Ltd., 7-2-1 Omika-cho, Hitachi-shi, Ibaraki-ken, 319-1221 Hitachi (Japan)

    2011-01-01

    A laser ultrasonics system was setup to measure the directivity (angular dependence pattern) of the amplitude of ultrasonic waves generated in aluminum samples. A pulsed Nd:YAG laser operating at 1064 nm optical wavelength, with typical pulse width (FWHM) of 8 ns, and energy per pulse of 450 mJ, was used to generate the ultrasound waves in the samples. The laser detection system was a Mach-Zehnder interferometer with typical noise-limited resolution of 0.25 nm (rms), frequency range from 50 kHz to 20 MHz, and measurement range from -75 nm/V to +75 nm/V. Two different optical spot sizes of the Nd:YAG laser were used to generate waves in the ablation regime: one was focused and the other was unfocused. Using the obtained data, the directivity graphics were drawn and compared with the theoretical curves, showing a good agreement. The experiments showed the directivity as a function of the optical spot size. For a point ultrasonic source (or focused optical spot), the directivity shows that the longitudinal waves present considerable amplitude in all directions. For a larger ultrasonic source (or an unfocused optical spot) the directivity shows that the longitudinal waves are generated with the higher amplitudes inside angles around {+-}10{sup 0}.

  11. Advanced welding for closed structure. Pt. 2 The ultrasonic approach

    Energy Technology Data Exchange (ETDEWEB)

    Sacripanti, A.; Paoloni, M.; Sagratella, G. [ENEA Centro Ricerche Casaccia, Rome (Italy). Dipt. Innovazione

    1999-07-01

    This report describes the activities developed for the European Contract BRITE AWCS III to study the use of ultrasonic sensing techniques to obtain an accurate detection of the internal reinforcement of the closed steel structures employed in the shipbuilding industry. After a description of the methods, techniques and problems for the ultrasonic testing of materials in the conventional approach, a new method of the multiple reflection-absorption is introduced with their experimental tests and results. The obtained conclusion shows that the ultrasonic non destructive testing techniques in the new approach should be useful to assemble a complete sensing system with two receivers, one thermal and one ultrasonic. [Italian] Questo rapporto descrive le attivita' sperimentali sviluppate nell'ambito del contratto europeo BRITE AWCS III, in cui si sono utilizzate tecniche ultrasoniche per ottenere un preciso rilevamento dei rinforzi interni di strutture metalliche chiuse utilizzate nell'industria delle costruzioni navali. Dopo la descrizione dei metodi, delle tecniche e dei problemi riguardanti il testing ultrasonico dei materiali, e' stato introdotto un approccio innovativo basato sul metodo dell'assorbimento delle riflessioni multiple con i risultati sperimentali. Le conclusioni ottenute mostrano che nel nuovo approccio, il testing ultrasonico non distruttivo dovrebbe essere utile per assemblare un sistema sensoriale con due sensori, uno di tipo termico, uno di tipo ultrasonico.

  12. Ultrasonic testing device for pipes with an acoustic coupling liquid

    International Nuclear Information System (INIS)

    System for the ultrasonic testing of tubes comprising: a probe consisting of an ultrasonic transducer integral with a mirror receiving the ultrasonic wave emitted by the transducer and centred according to the axis of the probe, a mechanism to move the probe inside the tube under inspection, facilities for detecting ultrasonic echoes returned by the tube. It also features facilities for introducing an acoustic coupling liquid in the capacity included between the tube, the transducer and the mirror when the probe enters the tube being tested as well as for drawing off this liquid when the probe is withdrawn from the tube. These facilities mainly include a soft bag tank filled with the liquid and located at the lower part of the probe and communicating with the capacity to be filled with the liquid. This bag becomes flat when entering the tube after the probe and thus pushes part of the liquid it contains towards this capacity. This liquid assembles again by gravity in the bag when it leaves the tube being tested and returns to its usual shape

  13. Directivity measurements in aluminum using a laser ultrasonics system

    Science.gov (United States)

    Sakamoto, J. M. S.; Tittmann, B. R.; Baba, A.; Pacheco, G. M.

    2011-01-01

    A laser ultrasonics system was setup to measure the directivity (angular dependence pattern) of the amplitude of ultrasonic waves generated in aluminum samples. A pulsed Nd:YAG laser operating at 1064 nm optical wavelength, with typical pulse width (FWHM) of 8 ns, and energy per pulse of 450 mJ, was used to generate the ultrasound waves in the samples. The laser detection system was a Mach-Zehnder interferometer with typical noise-limited resolution of 0.25 nm (rms), frequency range from 50 kHz to 20 MHz, and measurement range from -75 nm/V to +75 nm/V. Two different optical spot sizes of the Nd:YAG laser were used to generate waves in the ablation regime: one was focused and the other was unfocused. Using the obtained data, the directivity graphics were drawn and compared with the theoretical curves, showing a good agreement. The experiments showed the directivity as a function of the optical spot size. For a point ultrasonic source (or focused optical spot), the directivity shows that the longitudinal waves present considerable amplitude in all directions. For a larger ultrasonic source (or an unfocused optical spot) the directivity shows that the longitudinal waves are generated with the higher amplitudes inside angles around ±10°.

  14. Miniature, high efficiency transducers for use in ultrasonic flow meters

    Science.gov (United States)

    Saikia, Meghna

    This thesis is concerned with the development of a new type of miniature, high efficiency transducer for use in ultrasonic flow meters. The proposed transducer consists of a thin plate of a suitable piezoelectric material on which an inter-digital transducer is fabricated for the generation and detection of plate acoustic waves. When immersed in a fluid medium, this device can convert energy from plate acoustic waves (PAWs) into bulk acoustic waves (BAWs) and vice versa. It is shown that this mode coupling principle can be used to realize efficient transducers for use in ultrasonic flow meters. This transducer can be mounted flush with the walls of the pipe through which fluid is flowing, resulting in minimal disturbance of fluid flow. A prototype flow cell using these transducers has been designed and fabricated. The characteristics of this device have been measured over water flow rates varying from 0 to 7.5 liters per minute and found to be in good agreement with theory. Another attractive property of the new transducers is that they can be used to realize remotely read, passive, wireless flow meters. Details of methods that can be used to develop this wireless capability are described. The research carried out in this thesis has applications in several other areas such as ultrasonic nondestructive evaluation (NDE), noncontact or air coupled ultrasonics, and for developing wireless capability in a variety of other acoustic wave sensors.

  15. Developing an ultrasonic NDE system for a research reactor tank

    International Nuclear Information System (INIS)

    A special apparatus was developed for the ultrasonic inspection of a research reactor tank wall, from inside, without removal of the vessel top cover. The inspection is performed by the immersion technique using the coolant / moderator water as a medium for ultrasound transmission. A manipulator, carrying an ultrasonic search-unit is inserted into the tank through a central 70 mm diameter hole. The compact search unit carries up to 16 ultrasonic transducers, positioned at angular and straight orientations and operating both in pulse-echo and pitch-catch modes. The ultrasonic system is designed to scan the entire area of the tank wall with high resolution, to store the entire acquired data (full A-Scan) and to analyse it. It is capable of detecting 0.2 mm thickness variations, of corrosion pits of diameters greater than 3 mm and depths greater than 1 mm, and linear (crack-like) flaws in any orientation. The validation of the newly developed system, as well as of the inspection techniques, were carried out using a full-scale mock-up of a reactor tank, containing flaws unknown to the inspectors. (author)

  16. Specific ultrasonic inspection methods for steam generator tubes

    International Nuclear Information System (INIS)

    Framatome has developed a computerized equipment for inspecting PWR steam generator tubes using a rotating ultrasonic probe. Firstly devoted to the examination of the roll transition zone at the tube sheet secondary side level, the testing system can also operate now for inspections at the tube support plate levels. It is used independently for specific tube inspection, or it can be integrated into a broader-purpose system for sleeve weld testing, etc. The testing results are displayed in real time by means of two eight-level coded colored maps. Some applications, ranging from mockup testing to on-site inspection, are presented in this paper. In conclusion: An automated ultrasonic real-time imaging system for tube-wall thickness measurement, internal profilometry, and flaw detection, has been developed. This system has been successfully applied for on-site specific inspections within an industrial environment. In all cases the ultrasonic acquisition time was less than two minutes per tube. It should be pointed out that analysis of this new set of ultrasonic inspection results should also improve understanding of the in-service behaviour of these materials and components

  17. Application of Ultrasonic Techniques for Brain Injury Diagnosis

    International Nuclear Information System (INIS)

    In this work, we evaluate methods for detecting brain injury using ultrasound. We have used simulations of ultrasonic fields in the head to model the phase distortion of the skull. In addition we present experimental data from the crania of large animals. The experimental data help us understand and evaluate the performance of different transducers in acquiring the backscatter data from the brain through the skull. Both the simulations and acquired data illustrate the superiority of lower-frequency (<= 1 MHz) ultrasonic fields for transcranial acquisition of signals from inside the brain. Additionally, the experimental work shows that the higher-frequency (5 MHz) ultrasound can also be useful in acquiring clean nearfield data to help detect the position of the inner boundary of the skull

  18. Application of Ultrasonic Techniques for Brain Injury Diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Kasili, P.M.; Mobley, J.; Norton, S.J.; Vo-Dinh, T.

    1999-09-19

    In this work, we evaluate methods for detecting brain injury using ultrasound. We have used simulations of ultrasonic fields in the head to model the phase distortion of the skull. In addition we present experimental data from the crania of large animals. The experimental data help us understand and evaluate the performance of different transducers in acquiring the backscatter data from the brain through the skull. Both the simulations and acquired data illustrate the superiority of lower-frequency (<= 1 MHz) ultrasonic fields for transcranial acquisition of signals from inside the brain. Additionally, the experimental work shows that the higher-frequency (5 MHz) ultrasound can also be useful in acquiring clean nearfield data to help detect the position of the inner boundary of the skull.

  19. Atmospheric contamination during ultrasonic scaling

    NARCIS (Netherlands)

    Timmerman, MF; Menso, L; Steinfort, J; van Winkelhoff, AJ; van der Weijden, GA

    2004-01-01

    Objective: The aim of this study was to determine the microbial atmospheric contamination during initial periodontal treatment using a piezoelectric ultrasonic scaler in combination with either high-volume evacuation (HVE) or conventional dental suction (CDS). Methods: The study included 17 treatmen

  20. Ultrasonic characterization of CFRP anisotropy

    Czech Academy of Sciences Publication Activity Database

    Kling, M.; Tokar, Daniel; Převorovský, Zdeněk

    Praha: ČVUT v Praze, 2015 - (Hobza, T.), s. 71-80 ISBN 978-80-01-05841-1. [Stochastic and Physical Monitoring Systems 2015. Praha (CZ), 22.06.2015-27.06.2015] Institutional support: RVO:61388998 Keywords : anisotropy * carbon fiber -reinforced plastic * ultrasonic testing * signal processing Subject RIV: BI - Acoustics

  1. Ultrasonic testing of turbine blades by means of surface waves

    International Nuclear Information System (INIS)

    The use of modern intermetallic materials for turbine blades brings enormous weight advantages, but non-destructive testing is facing new challenges with regard to defect size. Even the smallest cracks must be detected reliably. Initial tests showed that a test using ultrasonic surface waves (Rayleigh waves) offer great potential here. The current state of basic research is presented. Furthermore, it is shown how this testing method could be implemented in the future in a production test sequence.

  2. Laser ultrasonic evaluation of human dental enamel during remineralization treatment

    OpenAIRE

    Wang, Hsiao-Chuan; Fleming, Simon; Lee, Yung-Chun; Swain, Michael; Law, Susan; Xue, Jing

    2011-01-01

    In this work a non-destructive laser ultrasonic technique is used to quantitatively evaluate the progressive change in the elastic response of human dental enamel during a remineralization treatment. The condition of the enamel was measured during two weeks treatment using laser generated and detected surface acoustic waves in sound and demineralized enamel. Analysis of the acoustic velocity dispersion confirms the efficacy, as well as illuminating the progress, of the treatment.

  3. Ultrasonic inspection of turbine rotor discs for stress corrosion cracking

    International Nuclear Information System (INIS)

    Stress corrosion cracking in turbine discs and keyways has been recognised for a number of years as a problem. Magnox Electric has devised and implemented a strategy to manage the threat from SCC, based on a probabilistic risk assessment technique. An important input to the risk assessment is a knowledge of existing defects and Magnox Electric has undertaken a major programme of work to develop ultrasonic inspection techniques and equipment for SCC detection and sizing in the relevant disc geometries. (author)

  4. Inservice surveillance and diagnostic ultrasonic system of steamgenerator tubing

    International Nuclear Information System (INIS)

    A versatile ultrasonic inspection system known as NERASON is described. NERASON offers fast, accurate, bore-side non-destructive examination of tubes with internal diameters less than 9mm. It can be used to detect and size complex structural faults and to determine sleeve weld integrity, wall thickness and ID profiles. It has many applications and here is described for the inspection of steam generator tubes in nuclear power plants. (UK)

  5. Development of ultrasonic immersion inspection technique for spent fuel canisters

    International Nuclear Information System (INIS)

    This report summarizes ultrasonic nondestructive testing development for metal matrix supported spent fuel disposal canisters. The work has concentated in two areas: inspection for lack of bond at the shell/matrix interface and inspection for voids in the matrix. The capabilities and limitations of these techniques have been fully established. Unbonded areas as small as 4 mm in diameter and voids 6 mm in diameter, 25 mm deep in the matrix, can readily be detected

  6. Residual stress profiling of an aluminum alloy by laser ultrasonics

    Institute of Scientific and Technical Information of China (English)

    PAN Yondong; QIAN Menglu; XU Weijiang; M. OURAK

    2004-01-01

    A residual-stress profile along the thickness of an aluminum alloy sheet is determined by laser-ultrasonic technique. Surface acoustic waves are generated by a Nd:YAG pulse laser and detected by a Heterodyne interferometer on a lateral free surface of the sheet. The distribution of residual stress is determined by measuring the relative variation of the wavevelocities at different location of the sample along its thickness. This technique is validated by three different residual stress profiles obtained experimentally.

  7. Complete inspection of friction stir welds in aluminum using ultrasonic and eddy current arrays

    International Nuclear Information System (INIS)

    Ultrasonic phased-array offers tremendous advantages for the inspection of Friction stir welds (FSW), a new method of joining metals using a solid state bonding process. Phased array ultrasonics can reliably detect all internal volumetric defects in FSW, such as cracks, inclusion, porosity and lack-of-penetration. Spot-focused beams improve detection, inspection angles can be optimized electronically and electronic scan of the beam normal to the welds gives rapid one-line scan inspection to assure full coverage. Furthermore, a technique using ultrasonic attenuation measurements shows the presence or absence of conditions for forming kissing bonds (or entrapped oxide defects). Also, eddy current arrays can be used for surface inspection, and can help to detect tight kissing bonds. Using all three approaches, the overall detection capability of kissing bonds is high. (author)

  8. Non-contact ultrasonic guided wave inspections of rails

    Science.gov (United States)

    Nguyen, Thompson V.; Mariani, Stefano; Lanza di Scalea, Francesco

    2014-03-01

    The University of California at San Diego (UCSD), under a Federal Railroad Administration (FRA) Office of Research and Development (R&D) grant, is developing a system for high-speed and non-contact rail integrity evaluation. A prototype using an ultrasonic air-coupled guided wave signal generation and air-coupled signal detection, in pair with a real-time statistical analysis algorithm, is under development. Experimental tests results, carried out at the UCSD Rail Defect Farm, indicate that the prototype is able to detect internal rail defects with high reliability. Extensions of the system are planned to add rail surface characterization to the internal rail defect detection.

  9. Survey report on unmanned site welding of austenitic stainless steel pipe and its ultrasonic examination

    International Nuclear Information System (INIS)

    In the field welding of austenitic stainless steel pipings and its non-destructive test in complicated and narrow places, reliable welding method and non-destructive testing method are required, and also, it is desirable to mechanize them (unmanned operation). In this study, the present state of the automatic welding of austenitic stainless steel pipings and ultrasonic flaw detection was investigated through the literatures in Japan and foreign countries. As the result, it was clarified that energetic research has been made recently to mechanize the welding, and though many points are left for future research and development, it is promising. In the ultrasonic flaw detection, many technical problems concerning the detectability of flaws remain at present, but is is expected to become feasible by future systematic research and development. The design of weld joints, the welding method and the remote automatic control of welding operation must be appropriate for guaranteeing the quality of welding, and these points were surveyed. The problems in the ultrasonic flaw detection are the attenuation of ultrasonic waves, the conditions of probes, the mode of wave motion and frequency, and the welding suitable to the ultrasonic flaw detection. (Kako, I.)

  10. Internal ultrasonic testing of steam generator tubes

    International Nuclear Information System (INIS)

    The ''in situ'' inspection of steam generator tubes uses generally Foucault currents before starting and along its life. This inspection aims at searching cracks and corrosion defects. The Foucault current method is quite badly adapted to ''closed crack'' detection, for it doesn't introduce neither resistivity or magnetic permeability variation, or lack of matter. More, it is sensible to the magnetic properties of the tube itself and to its environment (tubular or support plates). It is why, this first systematic inspection has to be completed by an ultrasonic one allowing to bring new elements in the uncertain cases. A device with an internal probe has been developed. It ''lights'' the tube wall with the aid of a transducer of which beam reflects on a mirror. Operating conditions are the same as for Foucault current testing, that is to say the probe moves inside the tube without rotation of the device (bent parts are excluded)

  11. Frogs Communicate by Means of Ultrasonic Sounds

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ People are always fascinated by ways that some members of mammalian species (such as dolphins, bats and some rodents) communicate using sounds that we cannot hear. But think twice if you say the capacity of producing and detecting ultrasounds (frequencies greater than 20kHz) is limited to mammalians. A study implemented by Prof. SHEN Junxian from the CAS Institute of Biophysics (IBP) and colleagues in CAS and abroad showed that a rare frog species in China should also be added to that list. It is the first documented case of a non-mammalian species being able to use ultrasonic communication. Their work was reported in the March 16 issue of the journal Nature.

  12. Intense ultrasonic clicks from echolocating toothed whales do not elicit anti-predator responses or debilitate the squid Loligo pealeii

    OpenAIRE

    Wilson, Maria; Hanlon, Roger T.; Tyack, Peter L; Madsen, Peter T.

    2007-01-01

    Toothed whales use intense ultrasonic clicks to echolocate prey and it has been hypothesized that they also acoustically debilitate their prey with these intense sound pulses to facilitate capture. Cephalopods are an important food source for toothed whales, and there has probably been an evolutionary selection pressure on cephalopods to develop a mechanism for detecting and evading sound-emitting toothed whale predators. Ultrasonic detection has evolved in some insects to avoid echolocating ...

  13. Ultrasonic characterization of centrifugally cast stainless steel samples

    International Nuclear Information System (INIS)

    The program for ultrasonic characterization of centrifugally cast stainless steel (CCSS) involves examining a broad sample set to determine the reliability of ultrasonics to detect and characterize flaws in CCSS piping. As part of this program, Amdata, Inc., participated in the PISC II international round robin. Battelle Pacific Northwest Laboratories (BPNL) conducted this round robin for the purpose of identifying methods that reliably detect flaws in CCSS. Fifteen pipe sections containing weldments made with material representative of PWR piping and one calibration block were inspected in 1985. The samples were provided by Battelle Pacific Northwest Laboratories as part of an international round robin for identifying methods and limitations for reliable detection of flaws in CCSS. Twelve of these samples were received by Amdata for re-examination on August 1, 1986. The other three have been destructively tested at BPNL. The destructive testing was performed for two reasons. The first was to verify the depth and extent of cracking in the samples. The second reason was to try to identify metallurgical reasons for the strong false indications of cracking that were observed in some samples. All of the samples currently being re-examined have had the backing plates removed and light machining performed to clean the inner diameter and outer diameter surfaces. In addition, the samples have been etched to confirm the grain structure. Dye-penetrant examinations were also performed. Four of the samples and the calibration block were ultrasonically imaged. The images of these samples are in agreement with last year's results

  14. Dynamic mode tuning of ultrasonic guided wave using an array transducer

    International Nuclear Information System (INIS)

    Ultrasonic guided waves have been widely employed for the long range inspection of structures such as plates, rods and pipes. In ultrasonic guided waves, however, there are numerous modes with different wave velocities, so that the generation and detection of the appropriate wave mode of the guided wave is one of key techniques in the application of guided waves. In the present work, phase tuning using an array transducer was applied to generate ultrasonic guided waves in a seamless stainless steel pipe. for this purpose, 8-channel ultrasonic pulser/receiver and their controller which enables sequential activation of each channels with given time delay were developed. Eight transducers were fabricated in order to generate guided waves by using an array transducer. The selective tuning of wave mode can be achieved by changing the interval between elements of an array transducer.

  15. An ultrasonic omni-directional sensor device for coverage structural deformation monitoring

    International Nuclear Information System (INIS)

    Underground space has to be monitored for regional coverage deformations. This issue remains a challenge for current deformation monitoring techniques. In this study, a new high-coverage regional monitoring method is presented to address underground space deformation by using the divergent feature of an ultrasonic sensor. The working principle for coverage regional monitoring, which uses the divergence feature of an ultrasonic beam to increase the monitoring area coverage, is proposed. Space and mathematical models for the ultrasonic beam are also established. An ultrasonic spherical sensor device is designed to achieve all-round monitoring of underground deformation. A longitude–latitude color map histogram is proposed, which enables automatic detection and tracking of omni-directional structural deformation. The new method is illustrated via experiments to determine its validity for deformation monitoring. (technical design note)

  16. Ultrasonic waves scattering through dissimilar welds: application to characterisation of spurious echoes detected during inspection; Etude de la diffusion des ondes ultrasonores dans les soudures austeno-ferritiques: application a la caracterisation des echos de lignes observes lors du controle des soudures bimetalliques

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, F

    1999-07-01

    Ultrasonic testing of bimetallic welds can show the presence of structural echoes. In pulse echo mode inspections at oblique incidence, these echoes are detected close to the back-wall (surface opposite to the control). These echoes have a specific shape: the amplitude is distributed along lines parallel to the weld sides. Such echoes can disturb the inspection: they can be misinterpreted as provided by a defect, or they can mask a possible defect. The aim of this thesis is to explain this phenomenon with an interpretation based on the anisotropic property of the weld. In such a structure, specific mode conversions in the lasts welding pass arise. Mode converted waves can reflect normally on the back-wall and therefore back propagate to the transducer along the same wave path as the forward propagation. Some generalities of ultrasonic testing of bimetallic welds are given in a preliminary chapter. In the first chapter, various experiments showed that these structural echoes do not result from beam deflection in the weld and that this phenomenon occurs in the last millimeters under the back-wall. According to these results, an interpretation for these echoes based on the anisotropic and the inhomogeneous structure of the weld is given in the last welding pass, oblique compression waves may be converted into normal shear waves. The second chapter presented a theoretical analysis of these mode conversions phenomenon between two metallurgical structures with different dendrite orientations. The analysis of the welding passes metallography and a bibliographic study summarizes on the relevancy to use a orthotropic symmetry to describe the metallurgical structure of the material under test. The third chapter deals with experimental studies to confirm this hypothesis. Detection of shear waves in the last welding passes near the back-wall mock-up using a specific sensor, able to discriminate the polarisation wave at the reception, validate the mode conversion hypothesis

  17. Bruce Thompson: Adventures and advances in ultrasonic backscatter

    Science.gov (United States)

    Margetan, Frank J.

    2012-05-01

    Over the course of his professional career Dr. R. Bruce Thompson published several hundred articles on non-destructive evaluation, the majority dealing with topics in ultrasonics. One longtime research interest of Dr. Thompson, with applications both to microstructure characterization and defect detection, was backscattered grain noise in metals. Over a 20 year period he led a revolving team of staff members and graduate students investigating various aspects of ultrasonic backscatter. As a member of that team I had the privilege of working along side Dr. Thompson for many years, serving as a sort of Dr. Watson to Bruce's Sherlock Holmes. This article discusses Dr. Thompson's general approaches to modeling backscatter, the research topics he chose to explore to systematically elucidate a better understanding of the phenomena, and the many contributions to the field achieved under his leadership. The backscatter work began in earnest around 1990, motivated by a need to improve inspections of aircraft engine components. At that time Dr. Thompson launched two research efforts. The first led to the heuristic Independent Scatterer Model which could be used to estimate the average grain noise level that would be seen in any given ultrasonic inspection. There the contribution from the microstructure was contained in a measureable parameter known as the Figure-of-Merit or FOM. The second research effort, spearheaded by Dr. Jim Rose, led to a formal relationship between FOM and details of the metal microstructure. The combination of the Independent Scattering Model and Rose's formalism provided a powerful tool for investigating backscatter in metals. In this article model developments are briefly reviewed and several illustrative applications are discussed. These include: the determination of grain size and shape from ultrasonic backscatter; grain noise variability in engine-titanium billets and forgings; and the design of ultrasonic inspection systems to improve defect

  18. Repeat scanning technology for laser ultrasonic propagation imaging

    International Nuclear Information System (INIS)

    Laser ultrasonic scanning in combination with contact or non-contact sensors provides new paradigms in structural health management (SHM) and non-destructive in-process quality control (IPQC) for large composite structures. Wave propagation imaging technology based on laser ultrasonic scanning and fixed-point sensing shows remarkable advantages, such as minimal need for embedded sensors in SHM, minimum invasive defect visualization in IPQC and general capabilities of curved and complex target inspection, and temporal reference-free inspection. However, as with other SHM methods and non-destructive evaluation based on ultrasound, the signal-to-noise ratio (SNR) is a prevalent issue in real structural applications, especially with non-contact thin-composite sensing or with thick and heterogeneous composites. This study proposes a high-speed repeat scanning technique for laser ultrasonic propagation imaging (UPI) technology, which is realized with the scanning speed of 1 kHz of a Q-switched continuous wave laser, and precise control of the laser beam pulses for identical point scanning. As a result, the technique enables the achievement of significant improvement in the SNR to inspect real-world composite structures. The proposed technique provides enhanced results for impact damage detection in a 2 mm thick wing box made of carbon-fiber-reinforced plastic, despite the low sensitivity of non-contact laser ultrasonic sensing. A field-applicable pure laser UPI system has been developed using a laser Doppler vibrometer as the non-contact ultrasonic sensor. The proposed technique enables the visualization of the disbond defect in a 15 mm thick wind blade specimen made of glass-fiber-reinforced plastic, despite the high dissipation of ultrasound in the thick composite. (paper)

  19. Acousto-Ultrasonics to Assess Material and Structural Properties

    Science.gov (United States)

    Kautz, Harold E.

    2002-10-01

    This report was created to serve as a manual for applying the Acousto-Ultrasonic NDE method, as practiced at NASA Glenn, to the study of materials and structures for a wide range of applications. Three state of the art acousto-ultrasonic (A-U) analysis parameters, ultrasonic decay (UD) rate, mean time (or skewing factor, "s"), and the centroid of the power spectrum, "fc," have been studied and applied at GRC for NDE interrogation of various materials and structures of aerospace interest. In addition to this, a unique application of Lamb wave analysis is shown. An appendix gives a brief overview of Lamb Wave analysis. This paper presents the analysis employed to calculate these parameters and the development and reasoning behind their use. It also discusses the planning of A-U measurements for materials and structures to be studied. Types of transducer coupling are discussed including contact and non-contact via laser and air. Experimental planning includes matching transducer frequency range to material and geometry of the specimen to be studied. The effect on results of initially zeroing the DC component of the ultrasonic waveform is compared with not doing so. A wide range of interrogation problems are addressed via the application of these analysis parameters to real specimens is shown for five cases: Case 1: Differences in density in 0 SiC/RBSN ceramic matrix composite. Case 2: Effect of tensile fatigue cycling in +/-45 SiC/SiC ceramic matrix composite. Case 3: Detecting creep life, and failure, in Udimet 520 Nickel-Based Super Alloy. Case 4: Detecting Surface Layer Formation in T-650-35/PMR-15 Polymer Matrix Composites Panels due to Thermal Aging. Case 5: Detecting Spin Test Degradation in PMC Flywheels. Among these cases a wide range of materials and geometries are studied.

  20. Fatigue Crack Measurement in Composite Materials by Ultrasonic Methods

    Science.gov (United States)

    Walker, James L.; Russell, Samuel S.; Suits, Michael W.; Workman, Gary L.; Watson, Jason M.; Thom, Robert (Technical Monitor)

    2002-01-01

    The nondestructive detection of intra-ply microcracking in unlined pressure vessels fabricated from composite materials is critical to ensuring mission success. Microcracking in composite structures due to combined fatigue and cryogenic thermal loading can be very troublesome to detect in-service and when it begins to link through the thickness can cause leakage and failure of the structure. These leaks may lead to loss of pressure/propellant, increased risk of explosion and possible cryo-pumping. The work presented herein develops a method and an instrument to locate and measure intraply fatigue cracking through the thickness of laminated composite material by means of correlation with ultrasonic resonance. Resonant ultrasound spectroscopy provides measurements which are, sensitive to both the microscopic and macroscopic properties of an object. Elastic moduli, acoustic attenuation, and geometry can all be probed. The approach is based on the premise of half-wavelength resonance. The method injects a broadband ultrasonic wave into the test structure using a swept frequency technique. This method provides dramatically increased energy input into the test article, as compared to conventional spike pulsed ultrasonics. This relative energy increase improves the ability to measure finer details in the materials character, such as micro-cracking and porosity. As the micro-crack density increases, more interactions occur with the higher frequency (small wavelength) components of the signal train causing the spectrum to shift toward lower frequencies. Preliminary experiments have verified a measurable effect on the resonance spectrum of the ultrasonic data to detect microcracking. Methods involving self organizing neural networks and other clustering algorithms show that the resonance ultrasound signatures from composites vary with the degree of microcracking and can be separated and identified.