Development of an ultrasound velocity profile monitor

Takeda, Yasushi

doi:10.1016/0029-5493(91)90117-z

Cited by 272 publications

(132 citation statements)

References 5 publications

Supporting

Mentioning

130

Contrasting

Unclassified

Order By: Relevance

“…UVP uses the 139 information on Doppler shift frequency contained in an ultrasound signal emitted by a probe and 140 echoed back by particles contained in the fluid. Each UVP probe measures the instantaneous flow 141 velocity at 128 points along its axis (see Takeda, 1991, for a technical explanation of the 142 methodology) extending 10 to 29 cm from the probe head in the configuration used. The orientation 143 of two or three probes can be arranged in order that their measurement axes intersect.…”

Section: Velocity 138mentioning

confidence: 99%

Flow Behavior of Ponded Turbidity Currents

Patacci¹,

Haughton²,

McCaffrey³

2015

Journal of Sedimentary Research

View full text Add to dashboard Cite

7Sea-floor topography can constrict, deflect, or reflect turbidity currents resulting in a range of 8 distinctive deposits. Where flows rebound off slopes and a suspension cloud collects in an enclosed 9 basin, ponded or contained turbidites are deposited. Ponded turbidites have been widely recognized 10 in slope mini-basins and on small, structurally confined basin floors in strike-slip and foreland-basin 11 settings. They can have a variable internal structure the significance of which remains poorly 12 understood in terms of flow behavior. New experiments demonstrate that the ponding process can 13 comprise up to four phases: 1) cloud establishment, 2) inflation, 3) steady-state maintenance, and 4) 14 collapse. The experiments explored the behavior of sustained turbidity currents draining into small 15 basins and show that the ponded suspensions that form are characterized by an important internal 16 interface; this divides a lower outbound-moving layer from an upper return layer. The basal layer 17 evolves to constant concentration and grain size, whereas the upper layer is graded (concentration 18 and grain size decrease upward). During the cloud inflation stage, the concentration and velocity 19 profiles of the ponded suspension evolve, and this phase can dominate the resulting deposit. 20Outbound internal waves can travel along the interface between the outbound and return layers and 21 impinge against the confining slope, and their amplitude is highest when the density contrast 22 between layers is greatest, e.g., when the input flows are thin and dense. The experiments show 23 that flow reversals can arise in several ways (initial rebound, episodic collapse of the wedge of fluid 24 above the counter slope, "grounding" of the internal velocity interface) and that despite steady 25 2 input, velocities decay and the deposit grades upwards. Internal waves emanate from the input 26 point, i.e., do not form as reflections off the counter slope. The internal grain-size interface within 27

show abstract

Section: Velocity 138mentioning

confidence: 99%

Flow Behavior of Ponded Turbidity Currents

Patacci¹,

Haughton²,

McCaffrey³

2015

Journal of Sedimentary Research

View full text Add to dashboard Cite

show abstract

“…Ultrasound velocimetry was developed and first used in water 8,9 and has since been applied to liquid metals including gallium 10,11 , sodium 12,13 , mercury 14 , lead-bismuth 15 , copper-tin 15 , and lead-lithium 16 , among others. Eckert et al provide a useful review of velocimetry in liquid metals 17 .…”

Section: Introductionmentioning

confidence: 99%

Ultrasound Velocity Measurement in a Liquid Metal Electrode

Perez

Kelley

2015

JoVE

View full text Add to dashboard Cite

A growing number of electrochemical technologies depend on fluid flow, and often that fluid is opaque. Measuring the flow of an opaque fluid is inherently more difficult than measuring the flow of a transparent fluid, since optical methods are not applicable. Ultrasound can be used to measure the velocity of an opaque fluid, not only at isolated points, but at hundreds or thousands of points arrayed along lines, with good temporal resolution. When applied to a liquid metal electrode, ultrasound velocimetry involves additional challenges: high temperature, chemical activity, and electrical conductivity. Here we describe the experimental apparatus and methods that overcome these challenges and allow the measurement of flow in a liquid metal electrode, as it conducts current, at operating temperature. Temperature is regulated within ±2 °C using a Proportional-Integral-Derivative (PID) controller that powers a custom-built furnace. Chemical activity is managed by choosing vessel materials carefully and enclosing the experimental setup in an argon-filled glovebox. Finally, unintended electrical paths are carefully prevented. An automated system logs control settings and experimental measurements, using hardware trigger signals to synchronize devices. This apparatus and these methods can produce measurements that are impossible with other techniques, and allow optimization and control of electrochemical technologies like liquid metal batteries. Video LinkThe video component of this article can be found at

show abstract

“…Since this pioneering work performed 20 years ago new ultrasonic measuring techniques were adapted to be applied successfully in liquid metal flows. [19][20][21] The used ultrasonic Doppler velocimetry (UDV) is a non-intrusive method which instantaneously delivers the liquid velocity profile along the ultrasonic beam. New developments of ultrasonic sensor arrays allow for a multidimensional flow mapping.…”

Section: Experimental Investigations Of Rotary Electromagnetic Mould mentioning

confidence: 99%

“…This method is based on the pulse-echo technique and delivers instantaneous profiles of the velocity component projected onto the propagation direction of the ultrasonic beam. 19) The measurements in the present study were performed using the DOP2000 velocimeter (model 2125, Signal Processing SA, 1073 Savigny, Switzerland). This instrument is equipped with an internal multiplexer allowing for sequential data acquisition from up to ten sensors.…”

Section: -Flow Measurement Techniquementioning

confidence: 99%