Journal articles: 'Instantaneous profile measurement'

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Wongsaroj, Wongsakorn, Ari Hamdani, Natee Thong-un, Hideharu Takahashi, and Hiroshige Kikura. "Ultrasonic Measurement of Velocity Profile on Bubbly Flow Using a Single Resonant Frequency." Proceedings 2, no. 8 (July 16, 2018): 549. http://dx.doi.org/10.3390/icem18-05445.

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The present paper describes a measurement technique for phase-separated velocity profile measurements in the two-phase bubbly flow. The Ultrasonic Velocity Profiler (UVP) method which is nonintrusive measurement, is applied to obtain an instantaneous velocity profile of liquid and bubble separately by using only one resonant frequency. To achieve this target, developed algorithm, which can decompose frequency component of the Doppler signal affected by liquid and bubble, is applied in the UVP system to obtain and separate instantaneous velocity profile of both phases. For confirming the applicability of modified measurement system, the developed UVP was used for the measurement of the velocity profile in bubbly flow on vertical pipe flow apparatus, the measurement accuracy was validated by UVP Original and Particle Image Velocimetry (PIV) method. Finally, the UVP was applied to experiment for observing velocity distribution of both phases in a bubble column.

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Takeda, Yasushi. "Instantaneous Velocity Profile Measurement by Ultrasonic Doppler Method." JSME International Journal Series B 38, no. 1 (1995): 8–16. http://dx.doi.org/10.1299/jsmeb.38.8.

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Sivakumar, N. R. "Large surface profile measurement with instantaneous phase-shifting interferometry." Optical Engineering 42, no. 2 (February 1, 2003): 367. http://dx.doi.org/10.1117/1.1532331.

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Wongsaroj, Wongsakorn, Ari Hamdani, Natee Thong-un, Hideharu Takahashi, and Hiroshige Kikura. "Extended Short-Time Fourier Transform for Ultrasonic Velocity Profiler on Two-Phase Bubbly Flow Using a Single Resonant Frequency." Applied Sciences 9, no. 1 (December 24, 2018): 50. http://dx.doi.org/10.3390/app9010050.

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This study introduces a measurement technique for simultaneous phase-separated velocity in two-phase bubbly flow. The non-invasive technique, based on an Ultrasonic Velocity Profiler (UVP), is used in order to obtain an instantaneous, separate velocity profile for both liquid and bubble. The aim of this paper is to measure each phase velocity at the same time and position it using only a single resonant frequency. To achieve this aim, extended signal processing of the Short-Time Fourier Transform (STFT) is proposed, combining with amplitude classification to analyze Doppler signal influenced from the bubbly flow. The use of developed algorithms allows the instantaneous separation of liquid and bubble velocity profiles. In this work, the developed technique is used to measure the velocity profile of bubbly flow in the vertical pipe, demonstrating the classification of liquid and bubble velocity. To confirm the accuracy of each velocity profile phase, the Particle Image Velocimetry (PIV) method is used for comparison. The results clarify that the proposed method is in good agreement with the PIV measurement. Finally, the effect of void fraction against velocity measurement of both phases was demonstrated.

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Tian, A. L., B. Li, M. T. Huang, and Zhuang De Jiang. "Instantaneous Measurement of 3D Profiles by Projecting Coded Grating." Key Engineering Materials 295-296 (October 2005): 495–500. http://dx.doi.org/10.4028/www.scientific.net/kem.295-296.495.

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A three-dimensional profile measurement system based on a projection coded grating technique is presented. The system uses a designing and decoding technique for grey coded gratings. The coded grating has black, white and grey stripes. The period triples a conventional grating. It greatly increases the height measuring range without any decrease in stripe separation. The shape of object can be obtained from only one grating image. The system is suitable for instantaneous measurement of moving objects including human face. The technique proposed permits rapid 3D measurement and no moving parts are involved in the system. The hardware is relatively simple. Special data processing software is developed. Results of a practical example confirm the effectiveness of the proposed method.

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Sivakumar, N. R., B. Tan, and K. Venkatakrishnan. "Measurement of surface profile in vibrating environment with instantaneous phase shifting interferometry." Optics Communications 257, no. 2 (January 2006): 217–24. http://dx.doi.org/10.1016/j.optcom.2005.07.056.

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Uehara, Kazuya, Seio Sengoku, and Hiroshi Amemiya. "Toothbrush Probe for Instantaneous Measurement of Radial Profile in Tokamak Boundary Plasma." Japanese Journal of Applied Physics 36, Part 1, No. 4A (April 15, 1997): 2351–55. http://dx.doi.org/10.1143/jjap.36.2351.

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Wang, Yu Tian, Hui Wang, and Qin Zhang. "Loudspeaker Nonlinear Distortion Signal Instantaneous Frequency Measurement and Analysis." Applied Mechanics and Materials 203 (October 2012): 83–87. http://dx.doi.org/10.4028/www.scientific.net/amm.203.83.

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Loudspeaker is a strongly nonlinear system which is associated with several situations such as electronic, magnetic, mechanical and acoustic. Recently, most of the methods used to measure and analysis loudspeaker are based on the FFT. Unfortunately, traditional Fourier transform based signal analysis method usually causes meaningless results when it is used to analysis non-stationary and nonlinear signal. In this paper, we use Hilbert-Huang transform (HHT) to review the instantaneous frequency of loudspeaker output. Experiments demonstrate that the distortion of loudspeaker can be recognized as intrawave frequency modulation caused by wave profile deformation. Then a novel nonlinear distortion measurement method is proposed which can reveal more accurate and physical meaningful characteristic of loudspeaker.

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Norbury, JR, Michael A. "MEASUREMENT OF INSTANTANEOUS PROFILE: A NEW GAUGING SYSTEM FOR HOT AND COLD ROLLING." Nondestructive Testing and Evaluation 12, no. 4 (January 1996): 263–72. http://dx.doi.org/10.1080/10589759608952850.

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Timm, Luís Carlos, Julio Cesar Martins de Oliveira, Tânia Toyomi Tominaga, Fábio Augusto Meira Cássaro, Klaus Reichardt, and Osny Oliveira Santos Bacchi. "Soil hydraulic conductivily measurement on a sloping field." Revista Brasileira de Engenharia Agrícola e Ambiental 4, no. 3 (December 2000): 480–82. http://dx.doi.org/10.1590/s1415-43662000000300027.

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A field methodology is presented for the measurement of the soil hydraulic conductivity in a sloping field, minimizing the leveling soil movement before water pounding and redistribution. The assurance of vertical flow only is performed through soil water potential isolines. The hydraulic conductivity was determined by the instantaneous profile method. Results for the nine neutron probe access tubes indicate that one single K(theta) relation is sufficient to represent the experimental site.

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Scheffler, Gregor A., and Rudolf Plagge. "Application of instantaneous profile measurement of moisture content and moisture potential in porous materials." Materials and Structures 44, no. 8 (March 18, 2011): 1517–36. http://dx.doi.org/10.1617/s11527-011-9716-y.

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Zhang, Yumei, and Dalin Zhang. "An Attitude Determination Method for Comprehensive Inspection Vehicle Based on Track Profile Registration." Periodica Polytechnica Transportation Engineering 45, no. 4 (May 30, 2017): 181. http://dx.doi.org/10.3311/pptr.10723.

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The attitude of the comprehensive inspection vehicle is one of the important factors that affect the accuracy of the inspection of metro line infrastructure, meanwhile the metro environment restricts the employment of common attitude determination methods. A new method of attitude determination is presented in this paper, which takes the track as reference and employs non-contact measurement to acquire the track profile simulta-neously. By registration of measurement track profile and the standard track profile, the relative position between the vehicle and the track reference can be calculated; and the instantaneous attitude of the vehicle can be determined by the matrix inverse calculation. The performance of the method is verified by an experiment using the road-rail comprehensive inspection vehicle.

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Tromp, Rutger R., and Lucas M. C. Cerioni. "Multiphase Flow Regime Characterization and Liquid Flow Measurement Using Low-Field Magnetic Resonance Imaging." Molecules 26, no. 11 (June 2, 2021): 3349. http://dx.doi.org/10.3390/molecules26113349.

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Multiphase flow metering with operationally robust, low-cost real-time systems that provide accuracy across a broad range of produced volumes and fluid properties, is a requirement across a range of process industries, particularly those concerning petroleum. Especially the wide variety of multiphase flow profiles that can be encountered in the field provides challenges in terms of metering accuracy. Recently, low-field magnetic resonance (MR) measurement technology has been introduced as a feasible solution for the petroleum industry. In this work, we study two phase air-water horizontal flows using MR technology. We show that low-field MR technology applied to multiphase flow has the capability to measure the instantaneous liquid holdup and liquid flow velocity using a constant gradient low flip angle CPMG (LFA-CPMG) pulse sequence. LFA-CPMG allows representative sampling of the correlations between liquid holdup and liquid flow velocity, which allows multiphase flow profiles to be characterized. Flow measurements based on this method allow liquid flow rate determination with an accuracy that is independent of the multiphase flow profile observed in horizontal pipe flow for a wide dynamic range in terms of the average gas and liquid flow rates.

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Ducharme, M. B., and J. Frim. "A multicouple probe for temperature gradient measurements in biological materials." Journal of Applied Physiology 65, no. 5 (November 1, 1988): 2337–42. http://dx.doi.org/10.1152/jappl.1988.65.5.2337.

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An easy-to-make, sensitive, thin, flexible, multisensor probe for in vivo tissue temperature profile measurement is described. It is essentially a multijunction thermocouple (i.e., a multicouple) of type-T composition. Enamel-insulated copper wires (38 gauge) were soldered 5 mm apart to one common uninsulated constantan wire (36 gauge) and introduced into a polyethylene tube sealed at one end. The total outside diameter of the multicouple probe is less than 1 mm, and the maximum number of junctions using the specified wire sizes is approximately 16. This design permits the instantaneous measurement of a tissue temperature profile at 5-mm intervals over a distance of approximately 8 cm. An extensive calibration for the thermal conductivity effect (k effect) along the multicouple wires by means of a limb model is presented. The results show that the temperature readings of the individual junctions are significantly affected by the k effect when a thermal gradient exists along the multicouple, as is usually the case during tissue temperature measurements. However, calibration of the multicouple for the k effect yields a measurement accuracy of +/- 0.1 degree C under a wide range of gradients. This probe can be implanted in tissues to measure thermal gradients under different physiological conditions.

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Suga, Kazuhiko, Yuka Nakagawa, and Masayuki Kaneda. "Spanwise turbulence structure over permeable walls." Journal of Fluid Mechanics 822 (June 1, 2017): 186–201. http://dx.doi.org/10.1017/jfm.2017.278.

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Spanwise flow field measurements are carried out for turbulent flows in channels with permeable bottom walls by particle image velocimetry (PIV) to understand the effects of the wall permeability on turbulence structure near porous walls. The porous media used are three kinds of foamed ceramics which have the same porosities (0.8) but different permeabilities. The turbulent flow fields in spanwise planes are discussed using instantaneous and statistical measurement data. At a small permeability Reynolds number ($Re_{K}$), low-speed and high-speed streaks, which are similar to those of solid-wall turbulence, are observed near the walls while at a large $Re_{K}$ the observed structure is very different from that of the solid-wall turbulence. It is found that the obtained spanwise scales of the structure can be reasonably correlated with the wall normal distance plus the zero-plane displacement which is estimated from the mean velocity profile. With the distribution profiles of the spanwise streak spacing and integral length scales, the transitional change of the turbulence structure over permeable walls is discussed.

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TSUJI, Toshiro, Yasutaka NAGANO, Masato TAGAWA, and Masashi HIGASHI. "Measurement of temperature fluctuations in a flow with cold-wire sensors. Instantaneous temperature profile and frequency response of sensors." Transactions of the Japan Society of Mechanical Engineers Series B 56, no. 529 (1990): 2704–11. http://dx.doi.org/10.1299/kikaib.56.2704.

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Lehr, A., and A. Bölcs. "Experimental Investigation of the Periodic Unsteady Transonic Flow Field Around a Compressor Blade by Means of Particle Image Velocimetry (PIV)." International Journal of Rotating Machinery 10, no. 5 (2004): 401–13. http://dx.doi.org/10.1155/s1023621x04000405.

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In the present article, a study of the time-dependent transonic flow field around an isolated airfoil in a Laval nozzle is presented. In order to obtain instantaneous flow field information all over the flow around the blade, the Particle Image Velocimetry (PIV) method has been employed allowing one to obtain velocity data in an illuminated light sheet with a high data acquisition rate and high spatial resolution. From these instantaneous PIV measurements the mean velocity field and turbulence quantities of the flow easily can be obtained by statistical means.A single compressor blade with a NACA 3506 profile and a chord length of 78 mm is centrally mounted in the test section. A vibration system driven by a hydraulic motor is externally attached to the blade. The rotational motion of the motor is translated to a plunging blade vibration perpendicular to the chord via an eccentric shaft and connecting arm. The vibration frequency can be varied between 0 and 100 Hz, and the average amplitude is approximately 0.4 mm. The entire blade-motor assembly is mounted to the tunnel sidewall via a circular disc to allow easy adjustment of the inlet flow incidence angle. The exit pressure of the nozzle can be varied by a rotating flat plate (15 mm high, 39 mm wide, and 2 mm thick) that is mounted approximately 5 times the chord length downstream of the blade mid-chord. The rotational frequency of this assembly can be varied between 0 and 100 Hz, producing upstream-running waves at the doubled frequency (i.e., 0 to 200 Hz). The above excitation systems can be precisely synchronized and the phase lag between them can be freely varied. This allows for unsteady measurements to be conducted in the presence of only the downstream perturbation, only the blade vibration, or a combination of the two for different phase angles.For the first test series the existing PIV measurement system at Turbomachinery Institute (LTT) has been applied to measure the transonic steady flow field around the compressor blade. In another test series, measurements of the time-dependent periodic flow field were conducted by means of PIV. This measurement series consisted of three subtasks: the measurement of the unsteady flow field with only back pressure variation, with only blade vibration, and finally with a combination of both back pressure variation and blade vibration. These results quantify not only the unsteady motion of the normal shock for each case on the suction side of the blade, but also give a detailed insight into the instantaneous transonic flow field around the compressor blade. Furthermore, the results of the set of unsteady measurements with both back pressure variation and blade vibration (3) is compared with the combination of the results of the sets of unsteady measurements of only back pressure variation (1) and only blade vibration (2) to validate the superposition principle.Finally, phase averaging of the instantaneous flowquantities produced a large database for statistical treatment (e.g., turbulence) and thus the ability to compare the averaged results with those from traditional measurement techniques.

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MORRIS, SCOTT C., SCOTT R. STOLPA, PAUL E. SLABOCH, and JOSEPH C. KLEWICKI. "Near-surface particle image velocimetry measurements in a transitionally rough-wall atmospheric boundary layer." Journal of Fluid Mechanics 580 (May 21, 2007): 319–38. http://dx.doi.org/10.1017/s0022112007005435.

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The Reynolds number dependence of the structure and statistics of wall-layer turbulence remains an open topic of research. This issue is considered in the present work using two-component planar particle image velocimetry (PIV) measurements acquired at the Surface Layer Turbulence and Environmental Science Test (SLTEST) facility in western Utah. The Reynolds number (δuτ/ν) was of the order 106. The surface was flat with an equivalent sand grain roughness k+ = 18. The domain of the measurements was 500 < yuτ/ν < 3000 in viscous units, 0.00081 < y/δ < 0.005 in outer units, with a streamwise extent of 6000ν/uτ. The mean velocity was fitted by a logarithmic equation with a von Kármán constant of 0.41. The profile of u′v′ indicated that the entire measurement domain was within a region of essentially constant stress, from which the wall shear velocity was estimated. The stochastic measurements discussed include mean and RMS profiles as well as two-point velocity correlations. Examination of the instantaneous vector maps indicated that approximately 60% of the realizations could be characterized as having a nearly uniform velocity. The remaining 40% of the images indicated two regions of nearly uniform momentum separated by a thin region of high shear. This shear layer was typically found to be inclined to the mean flow, with an average positive angle of 14.9°.

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Wulfmeyer, Volker, Shravan Kumar Muppa, Andreas Behrendt, Eva Hammann, Florian Späth, Zbigniew Sorbjan, David D. Turner, and R. Michael Hardesty. "Determination of Convective Boundary Layer Entrainment Fluxes, Dissipation Rates, and the Molecular Destruction of Variances: Theoretical Description and a Strategy for Its Confirmation with a Novel Lidar System Synergy." Journal of the Atmospheric Sciences 73, no. 2 (February 1, 2016): 667–92. http://dx.doi.org/10.1175/jas-d-14-0392.1.

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Abstract Atmospheric variables in the convective boundary layer (CBL), which are critical for turbulence parameterizations in weather and climate models, are assessed. These include entrainment fluxes, higher-order moments of humidity, potential temperature, and vertical wind, as well as dissipation rates. Theoretical relationships between the integral scales, gradients, and higher-order moments of atmospheric variables, fluxes, and dissipation rates are developed mainly focusing on the entrainment layer (EL) at the top of the CBL. These equations form the starting point for tests of and new approaches in CBL turbulence parameterizations. For the investigation of these relationships, an observational approach using a synergy of ground-based water vapor, temperature, and wind lidar systems is proposed. These systems measure instantaneous vertical profiles with high temporal and spatial resolution throughout the CBL including the EL. The resolution of these systems permits the simultaneous measurement of gradients and fluctuations of these atmospheric variables. For accurate analyses of the gradients and the shapes of turbulence profiles, the lidar system performances are very important. It is shown that each lidar profile can be characterized very well with respect to bias and system noise and that the constant bias has negligible effect on the measurement of turbulent fluctuations. It is demonstrated how different gradient relationships can be measured and tested with the proposed lidar synergy within operational measurements or new field campaigns. Particularly, a novel approach is introduced for measuring the rate of destruction of humidity and temperature variances, which is an important component of the variance budget equations.

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Bhansali, A. P., and W. Z. Black. "Local, Instantaneous Heat Transfer Coefficients for Jet Impingement on a Phase Change Surface." Journal of Heat Transfer 118, no. 2 (May 1, 1996): 334–42. http://dx.doi.org/10.1115/1.2825849.

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The local variation in the heat transfer coefficient for an axisymmetric, turbulent, submerged liquid jet impinging on a nonuniform boundary of a phase-change material is measured with an ultrasonic measurement technique. The time required for an acoustic wave to traverse the phase-change material is measured with an ultrasonic transducer and the time data are converted into local thickness profiles of the phase-change material via knowledge of the longitudinal acoustic velocity in the material. An energy balance at the melt interface between the impinging jet and the phase-change material is used in conjunction with the local thickness profile data to determine the local variation in the heat transfer coefficient. The phase-change material is originally flat, but its shape changes with time as the heated jet melts a complex shape into its surface. The heat transfer rate over the surface of the melting interface is shown to vary with time as a result of the changing shape of the phase change material. A deep cavity is melted into the solid at the stagnation point and secondary cavities are melted into the interface for certain jet flow rates and surface spacings between the jet nozzle and the melt interface. When secondary cavities are produced, secondary peaks in the local heat transfer coefficient are observed. The heat transfer data are formulated into two Nusselt number correlations that are functions of the dimensionless time, dimensionless radius, dimensionless jet-to-surface spacing, and jet Reynolds number. One correlation is formulated for all locations along the surface of the phase-change material except the stagnation point, and a second correlation is valid at the stagnation point.

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Laurentie, M. P., R. Garcia-Villar, P. L. Toutain, and J. Pelletier. "Pulsatile secretion of LH in the ram: a re-evaluation using a discrete deconvolution analysis." Journal of Endocrinology 133, no. 1 (April 1992): 75–85. http://dx.doi.org/10.1677/joe.0.1330075.

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ABSTRACT The purpose of the present experiment was to characterize LH secretion pulsatility in rams by analysing the instantaneous secretion rate profile obtained by deconvoluting the plasma concentration profile. Plasma LH concentration profiles were obtained by collecting blood samples every 6 min for 24 h during two different sessions separated by an interval of 15 days. Individual kinetic parameters of ovine LH (oLH) were determined following i.v. injection of oLH. By deconvoluting the plasma concentration profile, it was shown that a pulse has an effective duration of only 20·41±7·69 (s.d.) min whereas the mean duration estimated from measurement of plasma concentrations was 61·00 ± 15·16 min. The number of pulses was similar before and after deconvolution (7·80±1·99 vs 9·70 ± 3·44 pulses/24 h respectively). Using deconvolution the calculated production rate was 2·26 ± 0·94 μg/kg per 24 h, about 50% of this production being located in the pulses. Statistical analysis of pulsatility revealed that pulse occurrence was a non-periodic event and that the amplitude of LH pulses and the associated amount of LH released were correlated with the duration of the preceding quiescence period, but had no statistically significant influence on the duration of the following quiescence period. Journal of Endocrinology (1992) 133, 75–85

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ISHINO, Yojiro, Daiji OKAMOTO, and Norio OHIWA. "Three-Dimensional Instantaneous Measurement of Reaction Zone Profile of Turbulent Premixed Flames by Combining Multi-Lens Camera Photography and CT-Technique." Proceedings of Conference of Tokai Branch 2002.51 (2002): 195–96. http://dx.doi.org/10.1299/jsmetokai.2002.51.195.

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Y.*, Olotu, Omoakhalen A.I., Ososomi A.S., Gbalaja Mayowa, Alhassan A.I., and Ayilaran C.I. "Sensitivity of PR2 Capacitance Soil Moisture Meter for Irrigation Scheduling." Indian Journal of Production and Thermal Engineering 1, no. 3 (August 10, 2021): 1–5. http://dx.doi.org/10.35940/ijpte.b2007.081321.

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Accurate soil moisture content measurement is essential for designing a robust irrigation scheduling and integrated water resources management (I.W.R.M.). Capacitance-based sensors have widely been used to monitor soil moisture at different measuring depths coupled with continuous and instantaneous outputs. This study's objective was to evaluate the PR2 capacitance moisture meter's performance on mineral and organic soil water content. The outputs of PR2 in m3 /m3 and vol.% were compared with gravimetrically measured soil moisture. The R.M.S.E. measurement at Site A at the first and second replicates increased from 0.49% to 0.67%. In contrast, the r2 value of 0.99 was obtained for the two replications when comparing the soil moisture content observed from gravimetric measurement and the automated outputs from the PR2 Probe soil monitor. The R.M.S.E. values were 0.48%, and 1.32% were estimated for the first and second replications at Site B. The result indicates that the PR2 Profile Probe could be a reliable alternative to other time-consuming, complex computer algorithms for accurate point measurement of soil moisture.

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Satiennam, Thaned, Atthapol Seedam, Thana Radpukdee, Wichuda Satiennam, Warasak Pasangtiyo, and Yoshihiko Hashino. "Development of On-Road Exhaust Emission and Fuel Consumption Models for Motorcycles and Application through Traffic Microsimulation." Journal of Advanced Transportation 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/3958967.

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This study developed on-road exhaust emission and fuel consumption models for application in traffic microsimulations to estimate motorcycle emissions and fuel consumption in an Asian developing city. The motorcycle onboard measurement system was developed to instantaneously measure and continuously record on-road driving data, including the speed-time profile, exhaust emissions, and fuel consumption per second. The test motorcycle was driven on roads around Khon Kaen City, Thailand, to collect on-road driving data during the morning peak hours for a total of 112 hours. The collected on-road driving data were applied to develop on-road exhaust emission and fuel consumption models using regression analysis. The models were developed with high correlations among the amount of exhaust emissions and fuel consumption and the instantaneous speed and acceleration rate. The developed models were applied with a traffic microsimulation to evaluate the exclusive zone for motorcycles stopping at a signalized intersection. The evaluation results reveal that it could improve the level of intersection service by decreasing travel times, delays, and queue lengths at intersections, as well as by reducing the fuel consumption and emissions of vehicles travelling through intersections compared with these values under the existing conditions.

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Matrosov, Sergey Y., Peter T. May, and Matthew D. Shupe. "Rainfall Profiling Using Atmospheric Radiation Measurement Program Vertically Pointing 8-mm Wavelength Radars." Journal of Atmospheric and Oceanic Technology 23, no. 11 (November 1, 2006): 1478–91. http://dx.doi.org/10.1175/jtech1957.1.

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Abstract An attenuation-based method to retrieve vertical profiles of rainfall rate from vertically pointing Ka-band radar measurements has been refined and adjusted for use with the U.S. Department of Energy’s cloud radars deployed at multiple Atmospheric Radiation Program (ARM) test bed sites. This method takes advantage of the linear relationship between the rainfall rate and the attenuation coefficient, and can account for a priori information about the vertical profile of nonattenuated reflectivity. The retrieval method is applied to a wide variety of rainfall events observed at different ARM sites ranging from stratiform events with low-to-moderate rainfall rates (∼5 mm h−1) to heavy convective rains with rainfall rates approaching 100 mm h−1. The Ka-band attenuation-based retrieval results expressed in both instantaneous rainfall rates and in rainfall accumulations are compared to available surface data and measurements of a scanning C-band precipitation polarimetric radar located near the Darwin, Australia, ARM test bed site. The Ka-band retrievals are found to be in good agreement with the C-band radar estimates, which are based both on conventional radar reflectivity approaches and on polarimetric differential phase shift measurements. Typically, the C-band–Ka-band radar estimate differences are within the expected retrieval uncertainties. The magnitude of the Ka-band rainfall-rate estimate error depends on the retrieval resolution, rain intensity, and uncertainties in the profiles of nonattenuated reflectivity. It is shown that reasonable retrieval accuracies (∼15%–40%) can be achieved for a large dynamic range of observed rainfall rates (4–100 mm h−1) and the effective vertical resolution of about 1 km. The potential enhancements of the Ka-band attenuation-based method by including a priori information on vertical profiles of nonattenuated reflectivity and increasing the height range of the retrievals by using Ka-band polarization measurements are also discussed. The addition of the precipitation products to the suite of ARM hydrometeor retrievals can enhance the overall characterization of the vertical atmospheric column.

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Mrakic-Sposta, Simona, Maristella Gussoni, Michela Montorsi, Simone Porcelli, and Alessandra Vezzoli. "Assessment of a Standardized ROS Production Profile in Humans by Electron Paramagnetic Resonance." Oxidative Medicine and Cellular Longevity 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/973927.

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Despite the growing interest in the role of reactive oxygen species (ROS) in health and disease, reliable quantitative noninvasive methods for the assessment of oxidative stress in humans are still lacking. EPR technique, coupled to a specific spin probe (CMH: 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine) is here presented as the method of choice to gain a direct measurement of ROS in biological fluids and tissues. The study aimed at demonstrating that, differently from currently available “a posteriori” assays of ROS-induced damage by means of biomolecules (e.g., proteins and lipids) spin-trapping EPR provides direct evidence of the “instantaneous” presence of radical species in the sample and, as signal areas are proportional to the number of excited electron spins, lead to absolute concentration levels. Using a recently developed bench top continuous wave system (e-scan EPR scanner, Bruker) dealing with very low ROS concentration levels in small (50 μL) samples, we successfully monitored rapid ROS production changes in peripheral blood of athletes after controlled exercise and sedentary subjects after antioxidant supplementation. The correlation between EPR results and data obtained by various enzymatic assays (e.g., protein carbonyls and thiobarbituric acid reactive substances) was determined too. Synthetically, our method allows reliable, quick, noninvasive quantitative determination of ROS in human peripheral blood.

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ISHINO, Yojiro, Daiji OKAMOTO, and Norio OHIWA. "K-1503 Three-Dimensional Instantaneous Measurement of Reaction Zone Profile of Turbulent Premised Flames by Combining Multi-Lens Camera Photography and CT-Technique." Proceedings of the JSME annual meeting II.01.1 (2001): 297–98. http://dx.doi.org/10.1299/jsmemecjo.ii.01.1.0_297.

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Formosa, Danielle P., Huub M. Toussaint, Bruce R. Mason, and Brendan Burkett. "Comparative Analysis of Active Drag Using the MAD System and an Assisted Towing Method in Front Crawl Swimming." Journal of Applied Biomechanics 28, no. 6 (December 2012): 746–50. http://dx.doi.org/10.1123/jab.28.6.746.

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The measurement of active drag in swimming is a biomechanical challenge. This research compared two systems: (i) measuring active drag (MAD) and (ii) assisted towing method (ATM). Nine intermediate-level swimmers (19.7 ± 4.4 years) completed front crawl trials with both systems during one session. The mean (95% confidence interval) active drag for the two systems, at the same maximum speed of 1.68 m/s (1.40–1.87 m/s), was significantly different (p= .002) with a 55% variation in magnitude. The mean active drag was 82.3 N (74.0–90.6 N) for the MAD system and 148.3 N (127.5–169.1 N) for the ATM system. These differences were attributed to variations in swimming style within each measurement system. The inability to measure the early catch phase and kick, along with the fixed length and depth hand place requirement within the MAD system generated a different swimming technique, when compared with the more natural free swimming ATM protocol. A benefit of the MAD system was the measurement of active drag at various speeds. Conversely, the fixed towing speed of the ATM system allowed a natural self-selected arm stroke (plus kick) and the generation of an instantaneous force-time profile.

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Hoffmann, C. G., D. E. Kinnison, R. R. Garcia, M. Palm, J. Notholt, U. Raffalski, and G. Hochschild. "CO at 40–80 km above Kiruna observed by the ground-based microwave radiometer KIMRA and simulated by the whole atmosphere community climate model." Atmospheric Chemistry and Physics Discussions 12, no. 1 (January 6, 2012): 559–87. http://dx.doi.org/10.5194/acpd-12-559-2012.

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Abstract. This study compares CO in the Arctic stratosphere and mesosphere measured by ground-based microwave radiometry with simulations made with the Whole Atmosphere Community Climate Model driven with specified dynamical fields (SD-WACCM4) for the Arctic winters 2008/2009 and 2009/2010. CO is a tracer for polar winter middle atmosphere dynamics, hence the representation of polar dynamics in the model is examined indirectly. Measurements were taken with the Kiruna Microwave Radiometer (KIMRA). The instrument, which is located in Kiruna, Northern Sweden (67.8° N, 20.4° E), provides CO profiles between 40 and 80 km altitude. The present comparison, which is one of the first between SD-WACCM4 and measurements, is performed on the smallest space and time scales currently simulated by the model; the global model is evaluated daily at the particular model grid-point closest to Kiruna. As a guide to what can generally be expected from such a comparison, the same analysis is repeated for observations of CO from the Microwave Limb Sounder (MLS), a microwave radiometer onboard NASA's Aura satellite, which has global coverage. First, time-mean profiles of CO are compared, revealing that the profile shape of KIMRA deviates from SD-WACCM4 and MLS, especially in the upper mesosphere. SD-WACCM4 and MLS are mostly consistent throughout the range of altitude considered; however, SD-WACCM4 shows slightly lower values above 60 km and this discrepancy increases with altitude. Second, the time evolution is compared for the complete time series, as well as for the slowly and rapidly evolving parts alone. Overall, the agreement among the datasets is very good and the model is almost as consistent with the measurements as the measurements are with each other. Mutual correlation coefficients of the slowly varying part of the CO time series are ≥0.9 over a wide altitude range. This demonstrates that the polar winter middle atmosphere dynamics is very well represented in SD-WACCM4 and that the relaxation to analyzed meteorological fields below 50 km constrains the behavior of the simulation sufficiently, even at higher altitudes, such that the simulation above 50 km is close to the measurements. However, above 50 km, the model-measurement correlation for the rapidly varying part of the CO time series is lower (0.3) than the measurement-measurement correlation (0.6). This is attributed to the fact that the gravity wave parametrization in WACCM is based on a generic gravity wave spectrum and cannot be expected to capture the instantaneous behavior of the actual gravity wave field present in the atmosphere.

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30

Hoffmann, C. G., D. E. Kinnison, R. R. Garcia, M. Palm, J. Notholt, U. Raffalski, and G. Hochschild. "CO at 40–80 km above Kiruna observed by the ground-based microwave radiometer KIMRA and simulated by the Whole Atmosphere Community Climate Model." Atmospheric Chemistry and Physics 12, no. 7 (April 4, 2012): 3261–71. http://dx.doi.org/10.5194/acp-12-3261-2012.

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Abstract. This study compares CO in the Arctic stratosphere and mesosphere measured by ground-based microwave radiometry with simulations made with the Whole Atmosphere Community Climate Model driven with specified dynamical fields (SD-WACCM4) for the Arctic winters 2008/2009 and 2009/2010. CO is a tracer for polar winter middle atmosphere dynamics, hence the representation of polar dynamics in the model is examined indirectly. Measurements were taken with the KIruna Microwave RAdiometer (KIMRA). The instrument, which is located in Kiruna, Northern Sweden (67.8° N, 20.4° E), provides CO profiles between 40 and 80 km altitude. The present comparison, which is one of the first between SD-WACCM4 and measurements, is performed on the smallest space and time scales currently simulated by the model; the global model is evaluated daily at the particular model grid-point closest to Kiruna. As a guide to what can generally be expected from such a comparison, the same analysis is repeated for observations of CO from the Microwave Limb Sounder (MLS), a microwave radiometer onboard NASA's Aura satellite, which has global coverage. First, time-mean profiles of CO are compared, revealing that the profile shape of KIMRA deviates from SD-WACCM4 and MLS, especially in the upper mesosphere. SD-WACCM4 and MLS are mostly consistent throughout the range of altitude considered; however, SD-WACCM4 shows slightly lower values in the upper mesosphere. Second, the time evolution is compared for the complete time series, as well as for the slowly and rapidly evolving parts alone. Overall, the agreement among the datasets is very good and the model is almost as consistent with the measurements as the measurements are with each other. Mutual correlation coefficients of the slowly varying part of the CO time series are ≥0.9 over a wide altitude range. This demonstrates that the polar winter middle atmosphere dynamics is very well represented in SD-WACCM4 and that the relaxation to analyzed meteorological fields below 50 km constrains the behavior of the simulation sufficiently, even at higher altitudes, such that the simulation above 50 km is close to the measurements. However, above 50 km, the model-measurement correlation for the rapidly varying part of the CO time series is lower (0.3) than the measurement-measurement correlation (0.6). This is attributed to the fact that the gravity wave parametrization in WACCM is based on a generic gravity wave spectrum and cannot be expected to capture the instantaneous behavior of the actual gravity wave field present in the atmosphere.

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Barquero, Felix, Thomas Fichtner, and Catalin Stefan. "Methods of In Situ Assessment of Infiltration Rate Reduction in Groundwater Recharge Basins." Water 11, no. 4 (April 16, 2019): 784. http://dx.doi.org/10.3390/w11040784.

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As an alternative to the use of tracers, easy-to-measure soil moisture dynamic parameters (e.g., water content) provide in situ estimates of the infiltration rate reduction state of a soil medium. For instance, managed aquifer recharge operations control the hydraulic state of their infiltration basins by measuring the infiltrated volume under constant head conditions. Instantaneous profile measurement systems can be used to manage the basins by determining the reduction of the infiltration rate over time. This study combines the empirical methods of Libardi, the self-developed water content and root mean square difference-based procedures and the trigger time method, to get a similar reproduction of tracer results from river water spreading basins. The methods based on water content showed a good fitting in comparison to the results obtained with the tracer experiment and represent a promising source for detecting changes in the flow impedance during infiltration events.

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Gheni, Saba A., Mohammed F. Abed, Essam K. Halabia, and Saad R. Ahmed. "Investigation of carbon dioxide (CO2) capture in a falling film contactor by computer simulation." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 73 (2018): 43. http://dx.doi.org/10.2516/ogst/2018020.

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In this work, mathematical models of carbon dioxide (CO2) absorption by monoethanolamine amine (MEA) in a falling film contactor are developed. The proposed models aim to predict conversion of the gas–liquid reaction along the contactor, gas–liquid interface temperature profile (axial and radial), liquid film thickness along the contactor length, axial and radial concentration profiles of reactants in liquid film, and axial and radial profiles of velocity in the liquid film. A code written in MatLab was used to obtain these profiles based on multi grid method through programming of kinetic and thermodynamic equations and physical properties of the absorption system. The mathematical model is validated by an experimental measurement based on absorption of CO2 gas by MEA solution. Four parameters are studied as independent variables namely, mole fraction of carbon dioxide in gaseous mixture, molar concentration of absorbent (MEA, volumetric flow rate of MEA, and its temperature. It is found that the entrance effect of the falling film contactor is related to axial distance from the contactor entrance exponentially: E=B0exp(−B1y) An optimization technique based on minimization of the sum of the squared error between the experimental and predicted composition of absorption process is used to obtain B0 and B1. It is found that reaction between carbon dioxide and MEA is instantaneous, and the axial conversion of carbon dioxide in the gas phase varies exponentially with the contactor length.

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Bachrathy, Daniel, Adam K. Kiss, Attila Kossa, Szabolcs Berezvai, David Hajdu, and Gabor Stepan. "In-Process Monitoring of Changing Dynamics of a Thin-Walled Component During Milling Operation by Ball Shooter Excitation." Journal of Manufacturing and Materials Processing 4, no. 3 (August 3, 2020): 78. http://dx.doi.org/10.3390/jmmp4030078.

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During the milling of thin-walled workpieces, the natural frequencies might change radically due to the material removal. To avoid resonant spindle speeds and chatter vibration, a precise knowledge of the instantaneous modal parameters is necessary. Many different numerical methods exist to predict the changes; however, small unmodelled effects can lead to unreliable results. The natural frequencies could be measured by human experts based on modal analysis for an often interrupted process; however, this method is not acceptable during production. We propose an online measurement method with an automatic ball shooter device which can excite a wide frequency range of the flexible workpiece. The method is presented for the case of blade profile machining. The change of the natural frequencies is predicted based on analytical models and finite element simulations. The measurement response for the impulse excitation of the ball shooter device is compared to the results of impulse modal tests performed with a micro hammer. It is shown that the ball shooter is capable of determining even the slight variation of the natural frequencies during the machining process and of distinguishing the slight change caused by different clamping methods. An improved FE model is proposed to include the contact stiffness of the fixture.

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ISHINO, Yojiro, Daiji OKAMOTO, Takeshi FUJII, and Norio OHIWA. "Three-Dimensional Instantaneous Measurement of Reaction Zone Profile of Turbulent Premixed Flames by Combining Multi-Lens Camera Photography and CT-Technique : A Brief Discussion on Error Factors." Proceedings of thermal engineering conference 2002 (2002): 147–48. http://dx.doi.org/10.1299/jsmeptec.2002.0_147.

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35

Li, X., L. M. Zhang, and D. G. Fredlund. "Wetting front advancing column test for measuring unsaturated hydraulic conductivity." Canadian Geotechnical Journal 46, no. 12 (December 2009): 1431–45. http://dx.doi.org/10.1139/t09-072.

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Unsaturated hydraulic conductivity is the primary soil parameter required when performing seepage analyses for unsaturated–saturated soil systems. Unsaturated hydraulic conductivity is also one of the most difficult parameters to measure because of the time involved and the limited suction measurement range (e.g., 0∼1500 kPa in a test using the steady-state method). In this study, a new wetting front advancing method was developed for measuring unsaturated hydraulic conductivity. The wetting front advancing method simulates and monitors a soil wetting process through a large-scale soil column. A new interpretative procedure was developed to calculate the unsaturated hydraulic conductivity based on the monitored water content, suction, and wetting front advancing velocity. The proposed technique is used to measure the unsaturated hydraulic conductivities of five soils, which vary from gravel to clay. The results indicate that the proposed technique is time-saving (i.e., requires several days for a complete test) and is applicable over wide ranges of suctions and unsaturated hydraulic conductivities. The measured unsaturated hydraulic conductivity using the wetting front advancing method is similar to that obtained using the instantaneous profile method, with the latter covering narrower ranges of soil suction and hydraulic conductivity.

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36

Sun, Langqiu F., Bernd Milkereit, and Douglas R. Schmitt. "Measuring velocity dispersion and attenuation in the exploration seismic frequency band." GEOPHYSICS 74, no. 2 (March 2009): WA113—WA122. http://dx.doi.org/10.1190/1.3068426.

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No perfectly elastic medium exists in the earth. In an anelastic medium, seismic waves are distorted by attenuation and velocity dispersion. Velocity dispersion depends on the petrophysical properties of reservoir rocks, such as porosity, fractures, fluid mobility, and the scale of heterogeneities. However, velocity dispersion usually is neglected in seismic data processing partly because of the insufficiency of observations in the exploration seismic frequency band (∼5 through [Formula: see text]). The feasibility of determining velocity dispersion in this band is investigated. Four methods are used in measuring velocity dispersion from uncorrelated vibrator vertical seismic profile (VSP) data: the moving window crosscorrelation (MWCC) method, instantaneous phase method, time-frequency spectral decomposition method, and cross-spectrum method. The MWCC method is a new method that is satisfactorily robust, accurate, and efficient in measuring the frequency-dependent traveltime in uncorrelated vibrator records. The MWCC method is applied to the uncorrelated vibrator VSP data acquired in the Mallik gas hydrate research well. For the first time, continuous velocity dispersion is observed in the exploration seismic frequency band using uncorrelated vibrator VSP data. The observed velocity dispersion is fitted to a straight line with respect to log frequency to calculate [Formula: see text]. This provides an alternative method for [Formula: see text] measurement.

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37

Liu, Fuchao, Fan Yi, Zhenping Yin, Yunpeng Zhang, Yun He, and Yang Yi. "Measurement report: characteristics of clear-day convective boundary layer and associated entrainment zone as observed by a ground-based polarization lidar over Wuhan (30.5° N, 114.4° E)." Atmospheric Chemistry and Physics 21, no. 4 (March 1, 2021): 2981–98. http://dx.doi.org/10.5194/acp-21-2981-2021.

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Abstract. Knowledge of the convective boundary layer (CBL) and associated entrainment zone (EZ) is important for understanding land–atmosphere interactions and assessing the living conditions in the biosphere. A tilted 532 nm polarization lidar (30∘ off zenith) has been used for the routine atmospheric measurements with 10 s time and 6.5 m height resolution over Wuhan (30.5∘ N, 114.4∘ E). From lidar-retrieved aerosol backscatter, instantaneous atmospheric boundary layer (ABL) depths are obtained using the logarithm gradient method and Harr wavelet transform method, while hourly mean ABL depths are obtained using the variance method. A new approach utilizing the full width at half maximum of the variance profile of aerosol backscatter ratio fluctuations is proposed to determine the entrainment zone thickness (EZT). Four typical clear-day observational cases in different seasons are presented. The CBL evolution is described and studied in four developing stages (formation, growth, quasi-stationary and decay); the instantaneous CBL depths exhibited different fluctuation magnitudes in the four stages and fluctuations at the growth stage were generally larger. The EZT is investigated for the same statistical time interval of 09:00–19:00 LT. It is found that the winter and late autumn cases had an overall smaller mean (mean) and standard deviation (SD) of EZT data compared to those of the late spring and early autumn cases. This statistical conclusion was also true for each of the four developing stages. In addition, compared to those of the late spring and early autumn cases, the winter and late autumn cases had larger percentages of EZT falling into the subranges of 0–50 m but smaller percentages of EZT falling into the subranges of > 150 m. It seems that both the EZT statistics (mean and SD) and percentage of larger EZT values provide measures of entrainment intensity. Common statistical characteristics also existed. All four cases showed moderate variations of the mean of the EZT from stage to stage. The growth stage always had the largest mean and SD of the EZT and the quasi-stationary stage usually the smallest SD of the EZT. For all four stages, most EZT values fell into the 50–150 m subrange; the overall percentage of the EZT falling into the 50–150 m subrange between 09:00 and 19:00 LT was > 67 % for all four cases. We believe that the lidar-derived characteristics of the clear-day CBL and associated EZ can contribute to improving our understanding of the structures and variations of the CBL as well as providing a quantitatively observational basis for EZ parameterization in numerical models.

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Pietracho, Robert, Christoph Wenge, Stephan Balischewski, Pio Lombardi, Przemyslaw Komarnicki, Leszek Kasprzyk, and Damian Burzyński. "Potential of Using Medium Electric Vehicle Fleet in a Commercial Enterprise Transport in Germany on the Basis of Real-World GPS Data." Energies 14, no. 17 (August 27, 2021): 5327. http://dx.doi.org/10.3390/en14175327.

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The intensive electrification of the automotive sector means that the energy system must be able to adapt to the current market situation. The increase in energy demand is a major factor associated with electric vehicles. The study analyzed the operation of a grid-connected facility operating a vehicle fleet providing transport services in the region Halle/Saale, Germany. Measurement data were used in the analysis, including global positioning system data of the vehicles and technical data, including average fuel consumption on a given route section, daily load demand of the industrial facility, and energy generation from photovoltaics. This paper shows the impact of using a battery electric vehicles (BEVs) fleet in the load distribution for the industrial facility considered. The NEDC energy consumption profile for the Nissan e-NV200 were used in this study. Furthermore, the paper presented simulation results allowing one to determine the usage potential, energy demand, and consumption of EVs using real data, reliably representing the processes related to EV daily use. The measurement data were captured using available specialized equipment: Dako-Key (GPS data), PV power generation (Siemens 7KM PAC4200), and load (Janitza UMG 604-Pro) in September, 2018. On this basis, it is possible to identify the effects and variations in load on the power grid during the replacement of combustion vehicle fleets used currently by EVs for the provision of transport services. Three models were presented, making it possible to calculate changes in energy demand for each scenario. In the first model, EVs were charged exclusively from the distribution network. In the second, the energy generation from a renewable source was considered and the possibility of compensating the energy demand of the vehicles from this source was demonstrated. In the third model, the daily load profile and the period of maximum load in the electricity grid were considered. The results are presented in graphical and tabular form. Finally, the potential of using an EV fleet to increase the functionality of a modern industry object was determined and discussed. Based on data for the adopted scenarios, electrification of transport can increase demand for energy by 40.9% for individual enterprises. The electrification of the automotive sector will increase the instantaneous energy demand of businesses, forcing the integration of renewable energy sources during designing new invests.

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Ho, Je Ee. "Study the Relative Permeability of Ferrofluid with the Mean Value Analysis of Experimental Apparent Gravity." Advanced Materials Research 194-196 (February 2011): 533–36. http://dx.doi.org/10.4028/www.scientific.net/amr.194-196.533.

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Relative permeability is an important magnetic characteristic for ferrofluid to exhibit its magnetized potential during the magnetization process. To understand above physical property varying with field intensity, a popular analytic model, based on Langevin theory, has been usually considered and widely used. Unfortunately, an implicit model, derived from above hypothesis, for solving the instantaneous magnetization of ferro-particle will be carried out unless the determination of saturated magnetization should be conducted in advance. Just for the study dealing with magnetic property of testing ferro-sample is concerned, the previous acquisition of magnetization curve is impossible and unpractical without the precise measurement of magnetization-degree. On the other hand, required experimental expense is still so costly that it seems to be unaffordable for general laboratory. Thus a self-designed electromagnetic mechanism with special facility of smaller size, economical cost and efficient operation to quantify the reduced gravity of ferro-sample attracts our interest and is set up in this study. Meantime, an auxiliary numerical method, Newton interpolatory divided-difference formulas in trapezoidal rule, involved in this study successfully avoids the essentiality of saturated magnetization determined previously, and which also provides a numerical approximation through the weight loss of ferrofluid experienced by the designed experimental system. As compared with the result measured by VSM (vibration sample magnetometer) method, the estimated profile shows an excellent agreement except the extraordinary outcome occurring at B=6 mT, where a drastic increase of relative permeability will be evaluated due to the faster magnetization starts.

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ROBINSON, STEPHEN K. "INSTANTANEOUS VELOCITY PROFILE MEASUREMENTS IN A TURBULENT BOUNDARY LAYER." Chemical Engineering Communications 43, no. 4-6 (May 1986): 347–69. http://dx.doi.org/10.1080/00986448608911341.

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41

Taori, A., A. Jayaraman, K. Raghunath, and V. Kamalakar. "A new method to derive middle atmospheric temperature profiles using a combination of Rayleigh lidar and O<sub>2</sub> airglow temperatures measurements." Annales Geophysicae 30, no. 1 (January 5, 2012): 27–32. http://dx.doi.org/10.5194/angeo-30-27-2012.

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Abstract. The vertical temperature profiles in a typical Rayleigh lidar system depends on the backscatter photon counts and the CIRA-86 model inputs. For the first time, we show that, by making simultaneous measurements of Rayleigh lidar and upper mesospheric O2 temperatures, the lidar capability can be enhanced to obtain mesospheric temperature profile up to about 95 km altitudes. The obtained results are compared with instantaneous space-borne SABER measurements for a validation.

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ZHOU, QUAN, HENG-DONG XI, SHENG-QI ZHOU, CHAO SUN, and KE-QING XIA. "Oscillations of the large-scale circulation in turbulent Rayleigh–Bénard convection: the sloshing mode and its relationship with the torsional mode." Journal of Fluid Mechanics 630 (July 10, 2009): 367–90. http://dx.doi.org/10.1017/s0022112009006764.

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We report an experimental study of the large-scale circulation (LSC) in a turbulent Rayleigh–Bénard convection cell with aspect ratio unity. The temperature-extrema-extraction (TEE) method for obtaining the dynamic information of the LSC is presented. With this method, the azimuthal angular positions of the hot ascending and cold descending flows along the sidewall are identified from the measured instantaneous azimuthal temperature profile. The motion of the LSC is then decomposed into two different modes based on these two angles: the azimuthal mode and the translational or sloshing mode that is perpendicular to the vertical circulation plane of the LSC. Comparing to the previous sinusoidal-fitting (SF) method, it is found that both the TEE and the SF methods give the same information about the azimuthal motion of the LSC, but the TEE method in addition can provide information about the sloshing motion of the LSC. The sloshing motion is found to oscillate time-periodically around the cell's central vertical axis with an amplitude being nearly independent of the turbulent intensity and to have a π/2 phase difference with the torsional mode. It is further found that the azimuthal angular positions of the hot ascending and cold descending flows oscillate out of phase with each other by π, which leads to the observations of the torsional mode when these two flows are near the top and the bottom plates, respectively, and of the sloshing mode when they are both near the mid-height plane. A direct velocity measurement further confirms the existence of the bulk sloshing mode of the flow field.

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Kupari, M., V. Jarvinen, V. P. Poutanen, and P. Hekali. "Skewness of instantaneous mitral transannular flow-velocity profiles in normal humans." American Journal of Physiology-Heart and Circulatory Physiology 268, no. 3 (March 1, 1995): H1232—H1238. http://dx.doi.org/10.1152/ajpheart.1995.268.3.h1232.

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The spatial distribution of instantaneous diastolic flow velocities across the mitral annulus was studied with cardiac gated cine magnetic resonance imaging in 10 healthy persons aged 26–46 yr. Velocity encoding used two interleaved gradient echo pulse sequences with velocity sensitivity in the direction of flow perpendicular to the annular imaging plane. Velocity maps were reconstructed at 30- to 43-ms intervals throughout diastole. Velocity-time curves and mean flow rates were determined in five regions of the mitral annulus using a 0.6-cm2 measurement area. The spatial velocity minimum was consistently in the anterolateral commissural area, whereas the maximum was in the anterior annulus in early diastole shifting posteromedially in late diastole. The mean flow rate (+/- SD) averaged 18.4 +/- 8.1 ml.s-1.cm-2 of annular area centrally, 18.3 +/- 7.2 ml.s-1.cm-2 anteriorly, 16.9 +/- 7.4 ml.s-1.cm-2 posteriorly, 13.0 +/- 7.7 ml.s-1.cm-2 in the anterolateral commissural area, and 23.0 +/- 7.3 ml.s-1.cm-2 in the posteromedial commissural area (P < 0.001). We conclude that mitral transannular flow shows marked spatial inhomogeneity in normal humans. The skewness of flow profiles compromises the use of local velocity measurements as indexes of left ventricular filling.

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Komiyama, Masaharu, Masao Matsui, and Toshimi Takagi. "Measurements of Instantaneous Radial Temperature Profiles in Turbulent Diffusion Flames." Transactions of the Japan Society of Mechanical Engineers Series B 60, no. 572 (1994): 1443–48. http://dx.doi.org/10.1299/kikaib.60.1443.

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Fleming, Gary A., and Susan Althoff Gorton. "Measurement of Rotorcraft Blade Deformation Using Projection Moiré Interferometry." Shock and Vibration 7, no. 3 (2000): 149–65. http://dx.doi.org/10.1155/2000/342875.

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Projection Moiré Interferometry (PMI) has been used to obtain near instantaneous, quantitative blade deformation measurements of a generic rotorcraft model at several test conditions. These laser-based measurements provide quantitative, whole field, dynamic blade deformation profiles conditionally sampled as a function of rotor azimuth. The instantaneous nature of the measurements permits computation of the mean and unsteady blade deformation, blade bending, and twist. The PMI method is presented, and the image processing steps required to obtain quantitative deformation profiles from PMI interferograms are described. Experimental results are provided which show blade bending, twist, and unsteady motion. This initial proof-of-concept test has demonstrated the capability of PMI to acquire accurate, full field rotorcraft blade deformation data.

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Honda, Chikahisa, Mitsuo Maeda, Katsunori Muraoka, and Masanori Akazaki. "Rapid‐frequency‐scan laser for instantaneous line‐profile measurements in fluorescence spectroscopy." Review of Scientific Instruments 58, no. 5 (May 1987): 759–64. http://dx.doi.org/10.1063/1.1139627.

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Drahotský, Jakub, Pavel Hanzelka, Věra Musilová, Michal Macek, Ronald du Puits, and Pavel Urban. "Temperature profiles measurements in turbulent Rayleigh-Bénard convection by optical fibre system at the Barrel of II-menau." EPJ Web of Conferences 180 (2018): 02020. http://dx.doi.org/10.1051/epjconf/201818002020.

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Modelling of large-scale natural (thermally-generated) turbulent flows (such as the turbulent convection in Earth’s atmosphere, oceans, or Sun) is approached in laboratory experiments in the simplified model system called the Rayleigh-Bénard convection (RBC). We present preliminary measurements of vertical temperature profiles in the cell with the height of 4:7 m, 7:15m in diameter, obtained at the Barrel of Ilmenau (BOI), the worldwide largest experimental setup to study highly turbulent RBC, newly equipped with the Luna ODiSI-B optical fibre system. In our configuration, the system permits to measure the temperature with a high spatial resolution of 5mm along a very thin glass optical fibre with the length of 5m and seems to be perfectly suited for measurement of time series of instantaneous vertical temperature profiles. The system was supplemented with the two Pt100 vertically movable probes specially designed by us for reference temperature profiles measurements.

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KOMIYAMA, Masaharu, Hiroyuki KATOH, and Toshimi TAKAGI. "Measurements of Instantaneous Two-Dimensional Temperature Profiles in Turbulent Diffusion Flames." Transactions of the Japan Society of Mechanical Engineers Series B 62, no. 593 (1996): 361–67. http://dx.doi.org/10.1299/kikaib.62.361.

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Elsnab, John R., Jason P. Monty, Christopher M. White, Manoochehr M. Koochesfahani, and Joseph C. Klewicki. "High-fidelity measurements in channel flow with polymer wall injection." Journal of Fluid Mechanics 859 (November 26, 2018): 851–86. http://dx.doi.org/10.1017/jfm.2018.873.

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Streamwise velocity profiles and their wall-normal derivatives were used to investigate the properties of turbulent channel flow in the low polymer drag reduction$(DR)$regime ($DR=6.5\,\%$to$26\,\%$), as realized via polymer injection at the channel surface. Streamwise velocity data were obtained over a friction Reynolds number ranging from$650$to$1800$using the single-velocity-component version of molecular tagging velocimetry (1c-MTV). This adaptation of the MTV technique has the ability to accurately capture instantaneous profiles at very high spatial resolution (${\gtrsim}850$data points per wall-normal profile), and thus generate well-resolved derivative information as well. Owing to this ability, the present study is able to build upon and extend the recent numerical simulation analysis of Whiteet al. (J. Fluid Mech., vol. 834, 2018, pp. 409–433) that examined the mean dynamical structure of polymer drag-reduced channel flow at friction Reynolds numbers up to$1000$. Consistently, the present mean velocity profiles indicate that the extent of the logarithmic region diminishes with increasing polymer concentration, while statistically significant increases in the logarithmic profile slope begin to occur for drag reductions less than$15\,\%$. Profiles of the r.m.s. streamwise velocity indicate that the maximum moves farther from the wall and increases in magnitude with reductions in drag. Similarly, with increasing drag reduction, the profile of the combined Reynolds and polymer shear stress exhibits a decrease in its maximum value that also moves farther from the wall. Correlations are presented that estimate the location and value of the maximum r.m.s. streamwise velocity and combined Reynolds and polymer shear stress. Over the range of$DR$investigated, these effects consistently exhibit approximately linear trends as a function of$DR$. The present measurements allow reconstruction of the mean momentum balance (MMB) for channel flow, which provides further insights regarding the physics described in the study by Whiteet al. In particular, the present findings support a physical scenario in which the self-similar properties on the inertial domain identified from the leading-order structure of the MMB begin to detectably and continuously vary for drag reductions less than$10\,\%$.

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Pauzin, S., A. Giovannini, and B. Bédat. "Thin filament infrared pyrometry: instantaneous temperature profile measurements in a weakly turbulent hydrocarbon premixed flame." Experiments in Fluids 17, no. 6 (October 1994): 397–404. http://dx.doi.org/10.1007/bf01877042.

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Journal articles on the topic 'Instantaneous profile measurement'

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