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Measured Velocities (measured + velocity)
Selected AbstractsImproved understanding of velocity,saturation relationships using 4D computer-tomography acoustic measurementsGEOPHYSICAL PROSPECTING, Issue 2 2005K. Monsen ABSTRACT A recently developed laboratory method allows for simultaneous imaging of fluid distribution and measurements of acoustic-wave velocities during flooding experiments. Using a specially developed acoustic sample holder that combines high pressure capacity with good transparency for X-rays, it becomes possible to investigate relationships between velocity and fluid saturation at reservoir stress levels. High-resolution 3D images can be constructed from thin slices of cross-sectional computer-tomography scans (CT scans) covering the entire rock-core volume, and from imaging the distribution of fluid at different saturation levels. The X-ray imaging clearly adds a new dimension to rock-physics measurements; it can be used in the explanation of variations in measured velocities from core-scale heterogeneities. Computer tomography gives a detailed visualization of density regimes in reservoir rocks within a core. This allows an examination of the interior of core samples, revealing inhomogeneities, porosity and fluid distribution. This mapping will not only lead to an explanation of acoustic-velocity measurements; it may also contribute to an increased understanding of the fluid-flow process and gas/liquid mixing mechanisms in rock. Immiscible and miscible flow in core plugs can be mapped simultaneously with acoustic measurements. The effects of core heterogeneity and experimentally introduced effects can be separated, to clarify the validity of measured velocity relationships. [source] Comparison of velocity-log data collected using impeller and electromagnetic flowmetersGROUND WATER, Issue 3 2005M.W. Newhouse Previous studies have used flowmeters in environments that are within the expectations of their published ranges. Electromagnetic flowmeters have a published range from 0.1 to 79.0 m/min, and impeller flowmeters have a published range from 1.2 to 61.0 m/min. Velocity-log data collected in five long-screened production wells in the Pleasant Valley area of southern California showed that (1) electromagnetic flowmeter results were comparable within ±2% to results obtained using an impeller flowmeter for comparable depths; (2) the measured velocities from the electromagnetic flowmeter were up to 36% greater than the published maximum range; and (3) both data sets, collected without the use of centralizers or flow diverters, produced comparable and interpretable results. Although either method is acceptable for measuring wellbore velocities and the distribution of flow, the electromagnetic flowmeter enables collection of data over a now greater range of flows. In addition, changes in fluid temperature and fluid resistivity, collected as part of the electromagnetic flowmeter log, are useful in the identification of flow and hydrogeologic interpretation. [source] Measuring velocity distributions of viscous fluids using positron emission particle tracking (PEPT)AICHE JOURNAL, Issue 7 2004S. Bakalis Abstract Positron emission particle tracking (PEPT) can be used to trace the path of a radioactive particle within opaque fluids in pilot-scale equipment; the method can track particles through several centimeters of metal. PEPT has been successfully used to follow isokinetic tracers in viscous fluids and thus to measure velocity distributions under both isothermal and nonisothermal conditions in pipe flow. The accuracy of the method decreased as the measured velocities increased; the faster the particle traveled, the less accurate its detection. For velocities of up to 0.5 m/s the accuracy of the method was acceptable. Agreement between experimentally measured and theoretical velocity distributions was very good, for a range of fluids and process conditions. As tracer particles are used, there were problems ensuring that all parts of the measurement volume were sampled. This is possible to overcome to an extent by adjusting particle size; 600-,m tracers did not pass within 1 mm from the tube wall, whereas 240-,m particles passed much closer to the boundaries of the flow. © 2004 American Institute of Chemical Engineers AIChE J, 50: 1606,1613, 2004 [source] Kalman filter finite element method applied to dynamic ground motionINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 9 2009Yusuke Kato Abstract The purpose of this paper is to investigate the estimation of dynamic elastic behavior of the ground using the Kalman filter finite element method. In the present paper, as the state equation, the balance of stress equation, the strain,displacement equation and the stress,strain equation are used. For temporal discretization, the Newmark ¼ method is employed, and for the spatial discretization the Galerkin method is applied. The Kalman filter finite element method is a combination of the Kalman filter and the finite element method. The present method is adaptable to estimations not only in time but also in space, as we have confirmed by its application to the Futatsuishi quarry site. The input data are the measured velocity, acceleration, etc., which may include mechanical noise. It has been shown in numerical studies that the estimated velocity, acceleration, etc., at any other spatial and temporal point can be obtained by removing the noise included in the observation. Copyright © 2008 John Wiley & Sons, Ltd. [source] Experimental Investigation of thermal convection in an inclined narrow gap IIPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2009Daniel Rubes In the past decade the development in micro technology has experienced great progress, what made the knowledge of the flow behavior in small cavities fundamentally interesting. Our experimental contribution describes the measured temperature and velocity fields in a fluid containing inclined cavity with the dimensions 17 × 6 × 24 mm3 (w × d × h). Using PIV/T, we can determine the velocity and temperature distribution in the cavity simultaneously. The chamber is illuminated with a white light sheet of 1 mm. A 20% glycerin-water mixture is examined. The lower side is heated to 46.2°C, while the upper side has a constant temperature of 26°C. In this work we present the measured velocity and temperature fields of the fluid at different angles of the cavity orientation with respect to the direction of gravity in the stationary state. This is a continuation of last years presentation [1] in the sense that the temperature difference has been substantially increased. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||