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Method and apparatus for measuring flow velocity using matched filters

Description: An apparatus and method for measuring the flow velocities of individual phase flow components of a multiphase flow is disclosed. Signals arising from flow noise disturbance are extracted from the flow, at upstream and downstream locations. The signals are processed through pairs of matched filters which are matched to the flow disturbance frequency characteristics of the phase flow component to be measured. The processed signals are then cross-correlated to determine the transit delay time of the phase flow component between sensing positions.
Date: July 17, 1981
Creator: Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Development of acoustic flow instruments for solid/gas pipe flows

Description: Two nonintrusive acoustic flow sensing techniques are reported. One technique, passive in nature, simply measures the bandpassed acoustic noise level produced by particle/particle and particle/wall collisions. The noise levels, given in true RMS voltages or in autocorrelations, show a linear relationship to particle velocity but increase with solid concentration. Therefore, the passive technique requires calibration and a separate measure of solid concentration before it can be used to monitor the particle velocity. The second technique is based on the active cross-correlation principle. It measures particle velocity directly by correlating flow-related signatures at two sensing stations. The velocity data obtained by this technique are compared with measurements by a radioactive-particle time-of-flight (TOF) method. A multiplier of 1.53 is required to bring the acoustic data into agreement with the radioactive TOF result. The difference may originate from the difference in flow fields where particles are detected. The radioactive method senses particles mainly in the turbulent region and essentially measures average particle velocity across the pipe, while the acoustic technique detects particles near the pipe wall, and so measures the particle velocity in the viscous sublayer. Both techniques were tested in flows of limestone and air and 1-mm glass beads and air at the Argonne National Laboratory Solid/Gas Test Facility (SGFTF). The test matrix covered solid velocities of 20 to 30 m/s in a 2-in. pipe and solid-to-gas loading ratios of 6 to 22. 37 refs., 19 figs., 4 tabs.
Date: May 1, 1986
Creator: Sheen, S.H. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Signal analysis method using cross-correlation of turbulence flow signals to determine calibration of permanent magnet sodium flowmeters

Description: Permanent magnet flowmeters are used to measure flow in sodium cooled power plants both in the core and in plant piping. In this paper the cross-correlation technique and in particular the transfer function method is used to process the flow turbulence signals from electrodes spaced along the pipe in the vicinity of the magnetic field. Results from a loop flowmeter the EBR-II secondary flowmeter and a 400 mm diameter flowmeter are presented.
Date: January 1, 1977
Creator: Raptis, A.C. & Forster, G.A.
Partner: UNT Libraries Government Documents Department

Acoustic resonances in cylinder bundles oscillating in a compressibile fluid

Description: This paper deals with an analytical study on acoustic resonances of elastic oscillations of a group of parallel, circular, thin cylinders in an unbounded volume of barotropic, compressible, inviscid fluid. The perturbed motion of the fluid is assumed due entirely to the flexural oscillations of the cylinders. The motion of the fluid disturbances is first formulated in a three-dimensional wave form and then casted into a two-dimensional Helmholtz equation for the harmonic motion in time and in axial space. The acoustic motion in the fluid and the elastic motion in the cylinders are solved simultaneously. Acoustic resonances were approximately determined from the secular (eigenvalue) equation by the method of successive iteration with the use of digital computers for a given set of the fluid properties and the cylinders' geometry and properties. Effects of the flexural wavenumber and the configuration of and the spacing between the cylinders on the acoustic resonances were thoroughly investigated.
Date: December 1, 1984
Creator: Lin, W.H. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Remote detection of chemicals by millimeter-wave spectroscopy

Description: This paper discusses the development and field testing of a remote chemical detection system that is based on millimeter-wave (mm-wave) spectroscopy. The mm-wave system is a monostatic swept-frequency radar that consists of a mm-wave sweeper, a hot-electron-bolometer detector, and a trihedral reflector. The chemical plume to be detected is situated between the transmitter/detector and the reflector. Millimeter-wave absorption spectra of chemicals in the plume are determined by measuring the swept-frequency radar return signals with and without the plume in the beam path. The problem of pressure broadening, which hampered open-path spectroscopy in the past, has been mitigated in this work by designing a fast sweeping source over a broad frequency range. The heart of the system is a Russian backward-wave oscillator (BWO) tube that can be tuned over 225--315 GHz. A mm-wave sweeper that includes the BWO tube was built to sweep the entire frequency range within 10 ms. The radar system was field-tested at the DOE Nevada Test Site at a standoff distance of 60 m. Methyl chloride was released from a wind tunnel that produced a 2-m diameter plume at its exit point. The mm-wave system detected methyl chloride plumes down to a concentration of 12 ppm. The measurement results agree well with model-fitted data. Remote or standoff sensing of airborne chemicals is gaining importance for arms control and treaty verification, intelligence collection, and environmental monitoring.
Date: September 1, 1998
Creator: Gopalsami, N. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Determining bonding quality in polymer composites with a millimeter wave sensor

Description: Microwave nondestructive testing (NDT) techniques offer alternative solutions to other conventional NDT methods. Microwave/millimeter wave (determined roughly to cover 0.3 to 300 GHz) techniques are particularly useful for examination of dielectric composite materials that their low dielectric losses provide good depth of penetration of electromagnetic radiation in this band. Limitations associated with conventional NDT techniques such as high frequency ultrasonic testing (UT), namely, large variations in elastic properties of low density composite materials cause interpretation of complex UT signals difficult. Further, criticality of coupling of transducer to the sample surface limits the use of such techniques for on-line applications. High frequency microwave (millimeter waves, 30--300 GHz) systems compared to their low frequency counterparts offer higher resolution and sensitivity to variations in dielectric properties of low-loss composites. Further, higher frequencies render utilization of more compact systems which are often important for practical applications. A millimeter wave sensor is described in this work which can be utilized for non-contact NDT of a wide range of thin-sheet dielectric composite materials either as a laboratory-based instrument or for on-line quality control applications. Experimental results are presented on noncontact measurement of bonding quality in polyethylene/carbon composite samples. The w-band monostatic sensor operates based on measurement of the reflection properties of the material under test, which are then used to determine the volumetric uniformity of the joint area. Preliminary experimental results indicate the potential for the use of this sensor in fabrication process control of low-loss dielectric composite materials.
Date: December 1, 1996
Creator: Bakhtiari, S.; Gopalsami, N. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Advanced sensors for real-time control of advanced natural-gas reciprocating engine combustion.

Description: This is the final report of a three-year project under a Department of Energy Advanced Reciprocating Engine Systems contract. The goal of this project is to develop advanced sensors for real-time combustion monitoring of advanced natural-gas reciprocating engines. Two sensor technologies, ion-mobility spectrometry (IMS) and acoustic gas sensing, were tested for detection of NO{sub x} emissions and monitoring of natural-gas composition. This project examined two novel approaches: use of a corona/spark-discharge ionization source for IMS, and acoustic-relaxation spectra of natural gas for the acoustic gas sensor. We have completed evaluation of laboratory prototypes of both sensors. In this report, we will describe the basic elements of the sensors, their operating and detection principles, their performance, and other issues. Design modifications and suggested applications of field prototypes will also be presented.
Date: November 21, 2003
Creator: Sheen, S. H.; Chien, H. T. & Raptis, A. C.
Partner: UNT Libraries Government Documents Department

Near-field millimeter - wave imaging of nonmetallic materials

Description: A near-field millimeter-wave (mm-wave) imaging system has been designed and built in the 94-GHz range for on-line inspection of nonmetallic (dielectric) materials. The imaging system consists of a transceiver block coupled to an antenna that scans the material to be imaged; a reflector plate is placed behind the material. A quadrature IF mixer in the transceiver block enables measurement of in-phase and quadrature-phase components of reflected signals with respect to the transmitted signal. All transceiver components, with the exception of the Gunn-diode oscillator and antenna, were fabricated in uniform blocks and integrated and packaged into a compact unit (12.7 x 10.2 x 2.5 cm). The objective of this work is to test the applicability of a near-field compact mm-wave sensor for on-line inspection of sheetlike materials such as paper, fabrics, and plastics. This paper presents initial near-field mm-wave images of paper and fabric samples containing known artifacts.
Date: December 31, 1996
Creator: Gopalsami, N.; Bakhtiari, S. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Open-path millimeter-wave spectroscopy in the 225--315 GHz range

Description: This paper discusses the development of an open-path millimeter-wave (mm-wave) spectroscopy system in the 225--315 GHz atmospheric window. The new system is primarily a monostatic swept-frequency radar consisting of a mm-wave sweeper, hot-electron-bolometer or Schottky detector, and trihedral reflector. The heart of the system is a Russian backward-wave oscillator (BWO) tube that is tunable over 225--350 GHz. A mm-wave sweeper has been built with the BWO tube to sweep the entire frequency range within 1 s. The chemical plume to be detected is situated between the transmitter/receiver and the reflector. Millimeter-wave absorption spectra of chemicals in the plume are determined by measuring swept-frequency radar signals with and without the plume in the beam path. Because of power supply noise and thermal instabilities within the BWO structure over time, the BWO frequencies fluctuate between sweeps and thus cause errors in baseline subtraction. To reduce this frequency-jitter problem, a quasi-optical Fabry-Perot cavity is used in conjunction with the radar for on-line calibration of sweep traces, allowing excellent baseline subtraction and signal averaging. Initial results of the new system are given for open-path detection of chemicals.
Date: October 1, 1996
Creator: Gopalsami, N.; Bakhtiari, S. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Ultrasonic wave propagation in multilayered piezoelectric substrates

Description: Due to the increasing demand for higher operating frequency, lower attenuation, and stronger piezoelectricity, use of the layered structure has become necessary. Theoretical studies are carried out for ultrasonic waves propagating in the multilayered piezoelectric substrates. Each layer processes up to as low as monoclinic symmetry with various thickness and orientation. A plane acoustic wave is assumed to be incident, at varied frequency and incidence angle, from a fluid upon a multilayered substrate. Simple analytical expressions for the reflection and transmission coefficients are derived from which all propagation characteristics are identified. Such expressions contain, as a by-product, the secular equation for the propagation of free harmonic waves on the multilayered piezoelectric substrates. Solutions are obtained for the individual layers which relate the field variables at the upper layer surfaces. The response of the total system proceeds by satisfying appropriate interfacial conditions across the layers. Based on the boundary conditions, two cases, {open_quotes}shorted{close_quotes} and {open_quotes}free{close_quotes}, are derived from which a so-called piezoelectric coupling factor is calculated to show the piezoelectric efficiency. Our results are rather general and show that the phase velocity is a function of frequency, layer thickness, and orientation.
Date: April 11, 1994
Creator: Chien, H.T.; Sheen, S.H. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

In-line ultrasonic monitoring of waste slurry suspended solids

Description: During the transport of tank waste, it is very important to quantitatively measure the percent solids concentration (PSC) of the waste, which indicates the flow conditions and the extent of solids settling. At Argonne National Laboratory, an in-line, real-time, a nonintrusive ultrasonic monitoring system has been developed to measure the PSC and flow density of tank waste by measuring sound velocity and attenuation in the flow. This system consists of a pair of longitudinal transducers bonded to waveguides on the opposite sides of the pipe and operating at IMHz simultaneously in pulse-and-echo and pitch-and-catch modes. The PSC measurement is provided by attenuation, while the density measurement is calculated by impedance and sound velocity. A thermocouple is attached to one of the waveguides for automatic temperature correction of the measurements. This system was one of four evaluated for in-line measurement of slurry at Oak Ridge National Laboratory in 1998. The results indicate that the measurements are in good agreement with a Coriolis meter and that the system can be used to monitor PSC up to 40 wt.%. However, the system is greatly affected by entrained air bubbles within the solid flow during Puisair mixing. A different mixing mechanism will solve this problem.
Date: May 25, 2000
Creator: Chien, H.-T.; Sheen, S.-H. & Raptis, A. C.
Partner: UNT Libraries Government Documents Department

Development of a magnetic resonance sensor for on-line monitoring of {sup 99}Tc and {sup 23}Na in tank waste cleanup processes: Final report and implementation plan

Description: In response to US Department of Energy (DOE) requirements for advanced cross-cutting technologies, Argonne National Laboratory is developing an on-line sensor system for the real-time monitoring of {sup 99}Tc and {sup 23}Na in various locations throughout radioactive-waste processing facilities. Based on nuclear magnetic resonance spectroscopy, the highly automated sensor system can provide near-real-time response with minimal sampling. The technology, in the form of a flow-through nuclear-magnetic-resonance-based on-line process sensing and control system, can rapidly monitor {sup 99}Tc speciation and concentration (from 0.1 molar to 10 micro molar) in the feedstocks and eluents of radioactive-waste treatment processes. The system is nonintrusive, capable of withstanding harsh plant environments, and reasonably immune to contaminants. Furthermore, the system is capable of operating over large variations in pH, conductivity, and salinity. This document describes design parameters, results from sensitivity studies, and initial results obtained from oxidation-reduction studies that were conducted on technetium standards and waste specimens obtained from DOE's Hanford site. A cursory investigation of the system's capabilities to monitor {sup 23}Na at high concentrations are also reported, as are descriptions of site requirements, implementation recommendations, and testing techniques.
Date: February 24, 2000
Creator: Dieckman, S. L.; Jendrzejczyk, J. A. & Raptis, A. C.
Partner: UNT Libraries Government Documents Department

An application of wavelet transforms and neural networks for decomposition of millimeter-wave spectroscopic signals

Description: This paper reports on wavelet-based decomposition methods and neural networks for remote monitoring of airborne chemicals using millimeter wave spectroscopy. Because of instrumentation noise and the presence of untargeted chemicals, direct decomposition of the spectra requires a large number of training data and yields low accuracy. A neural network trained with features obtained from a discrete wavelet transform is demonstrated to have better decomposition with faster training time. Results based on simulated and experimental spectra are presented to show the efficacy of the wavelet-based methods.
Date: July 1, 1995
Creator: Gopalan, K.; Gopalsami, N.; Bakhtiari, S. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Automotive vehicle sensors

Description: This report is an introduction to the field of automotive vehicle sensors. It contains a prototype data base for companies working in automotive vehicle sensors, as well as a prototype data base for automotive vehicle sensors. A market analysis is also included.
Date: September 1, 1995
Creator: Sheen, S.H.; Raptis, A.C. & Moscynski, M.J.
Partner: UNT Libraries Government Documents Department

Development of a millimeter-wave sensor for environmental monitoring

Description: A millimeter-wave (mm-wave) sensor in the frequency range of 225-315 GHz is being developed for continuous emission monitoring of airborne effluents from industrial sites for environmental compliance monitoring and process control. Detection of chemical species is based on measuring the molecular rotational energy transitions at mm-wave frequencies. The mm-wave technique offers better transmission properties compared to optics in harsh industrial environments with smoke, dust, aerosols, and steam, as well as in adverse atmospheric conditions. The laboratory measurements indicate that polar molecules can be measured with a sensitivity of tens of parts-per-million-meter using this technology. Proof of principle of the open-path system was tested by releasing and detecting innocuous chemicals in the open air. It uses a monostatic radar configuration with transmitter and receiver on one side and a comer cube on tire other side of the plume to be measured. A wide-band swept frequency mm-wave signal is transmitted through the plume and return signal from the comer cube is detected by a hot-electron-bolometer. Absorption spectra of plume gases are measured by comparing the return signals with and without the plume in the beam path. Using signal processing based on deconvolution, high specificity of detection has been shown for resolving individual chemicals from a mixture. This technology is applicable for real-time measurement of a suite of airborne gases/vapors emitted from vents and stacks of process industries. A prototype sensor is being developed for wide-area monitoring of industrial sites and in-place monitoring of stack gases.
Date: June 1, 1995
Creator: Gopalsami, N.; Bakhtiari, S. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

An on-line NMR technique with a programmable processor

Description: Nuclear magnetic resonance (NMR) spectroscopy is used to determine molecular content of materials, mainly in laboratory measurements. The reduced cost of fast computer processors, together with recent break throughs in digital signal processor technology, has facilitated the on-line use of NMR by allowing modifications of the available technology. This paper describes a system and an algorithm for improving the on-line operations. It is base on the time-domain NMR signal detected by the controller and some prior knowledge of chemical signal patterns. The desired signal can be separated from a composite signal by using an adaptive line enhancer (ALE) filter. This technique would be useful for upgrading process procedures in on-line manufacturing.
Date: July 1, 1995
Creator: Razazian, K.; Dieckman, S.L. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

User Interface Program for secure electronic tags

Description: This report summarizes and documents the efforts of Argonne National Laboratory (ANL) in developing a secure tag communication user interface program comprising a tag monitor and a communication tool. This program can perform the same functions as the software that was developed at the Lawrence Livermore National Laboratory (LLNL), but it is enhanced with a user-friendly screen. It represents the first step in updating the TRANSCOM Tracking System (TRANSCOM) by incorporating a tag communication screen menu into the main menu of the TRANSCOM user program. A working version of TRANSCOM, enhanced with ANL secure-tag graphics, will strongly support the Department of Energy Warhead Dismantlement/Special Nuclear Materials Control initiatives. It will allow commercial satellite tracking of the movements and operational activities of treaty-limited items and transportation vehicles throughout Europe and the former USSR, as well as the continental US.
Date: May 1, 1995
Creator: Cai, Y.; Koehl, E.R.; Carlson, R.D. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

DSP-based on-line NMR spectroscopy using an anti-Hebbian learning algorithm

Description: This paper describes a nuclear magnetic resonance (NMR) system that uses an adaptive algorithm to carry out real-time NMR spectroscopy. The system employs a digital signal processor (DSP) chip to regulate the transmitted and received signal together with spectral analysis of the received signal to determine free induction decay (FID). To implement such a signal-processing routine for detection of the desired signal, an adaptive line enhancer filter that uses an anti-Hebbian learning algorithm is applied to the FID spectra. The results indicate that the adaptive filter can be a reliable technique for on-line spectroscopy study.
Date: July 1, 1995
Creator: Razazian, K.; Dieckman, S.L.; Raptis, A.C. & Bobis, J.P.
Partner: UNT Libraries Government Documents Department

Detection and location of leaks in district heating steam systems: Survey and review of current technology and practices

Description: This report presents the results of a survey undertaken to identify and characterize current practices for detecting and locating leaks in district heating systems, particular steam systems. Currently used technology and practices are reviewed. In addition, the survey was used to gather information that may be important for the application of acoustic leak detection. A few examples of attempts to locate leaks in steam and hot water pipes by correlation of acoustic signals generated by the leaks are also discussed.
Date: March 1, 1992
Creator: Kupperman, D.S.; Raptis, A.C. & Lanham, R.N.
Partner: UNT Libraries Government Documents Department

Ultrasonic flow imaging system: A feasibility study

Description: This report examines the feasibility and potential problems in developing a real-time ultrasonic flow imaging instrument for on-line monitoring of mixed-phased flows such as coal slurries. State-of-the-art ultrasonic imaging techniques are assessed for this application. Reflection and diffraction tomographies are proposed for further development, including image-reconstruction algorithms and parallel processing systems. A conventional ultrasonic C-scan technique is used to demonstrate the feasibility of imaging the particle motion in a solid/water flow. 13 refs., 11 figs.
Date: September 1, 1991
Creator: Sheen, S.H.; Lawrence, W.P.; Chien, H.T. & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

An acousto-ultrasonic NDE technique for monitoring material anisotropy

Description: A simpler and better way of monitoring the anisotropy of fiber-reinforced composite materials, based on the acousto-ultrasonic approach, is presented. In this approach, time of flight of the acousto-ultrasonic waves AU, rather than the stress wave factor, is measured. Two fundamental Lamb modes are generated under the first critical frequency: one is the first antisymmetric mode traveling with a slower velocity while the another is the first symmetric mode traveling with a faster speed. The later one is sensitive to the azimuthal angle and nearly nondispersive, and has a phase velocity very close to that of the bulk longitudinal wave of the material. Experimental data measured from two methods, TOF measurement and slope method, are compared with theoretical results; a good agreement is obtained for monitoring the material anisotropy. There is a great potential for this AU approach in material-property evaluation and in quantitative measurements of defects and debonding of fiber-reinforced composites. However, more studies are needed to better understand the effect of the fiber/matrix bonding on the measurements and to extract more information from the AU signals.
Date: August 1, 1992
Creator: Chien, Hual Te; Sheen, Shuh Haw & Raptis, A.C.
Partner: UNT Libraries Government Documents Department

Microwave radar detection of gas pipeline leaks.

Description: We are developing a microwave radar sensing and imaging system to detect and locate gas leaks in natural gas pipelines. The underlying detection principle is radar backscattering from the index-of-refraction inhomogeneities introduced by the dispersion of methane in air. An essential first step in the development effort is modeling to estimate the radar cross section. This paper describes the modeling results and the experimental efforts underway to validate the model. For the case of leaks from small holes in a pressurized gas pipeline, we modeled the gas dynamics of the leak jet to determine the plume geometry and the variation of methane concentration in air as a function of distance from the leak source. From the static and dynamic changes in the index of refraction in the turbulent plume, the radar backscatter cross sections were calculated. The results show that the radar cross sections of the leak plumes should be detectable by special-purpose radars.
Date: October 2, 2002
Creator: Gopalsami, N.; Kanareykin, D. B.; Asanov, V. D; Bakhtiari, S. & Raptis, A. C.
Partner: UNT Libraries Government Documents Department

Development of a hand-portable photoionization time-of-flight mass spectrometer

Description: ANL is currently developing a portable chemical sensor system based on laser desorption photoionization time-of-flight mass spectrometry. It will incorporate direct sampling, a cryocooler base sample adsorption and concentration, and direct surface multiphoton ionization. All components will be in a package 9 x 11 x 4 in., weighing 15-18 lbs. A sample spectrum is given for a NaCl sample.
Date: June 1996
Creator: Dieckman, S. L.; Bostrom, G. A.; Waterfield, L. G.; Jendrzejczyk, J. A. & Raptis, A. C.
Partner: UNT Libraries Government Documents Department