Flow velocity measurement

Doppler transthoracic echocardiography is routinely performed to measure peak mitral inflow velocities in the assessment of left ventricular diastolic function. The limitations of echocardiography are well documented, but its accuracy in the measurement of transmitral peak velocity in the presence of aortic valve regurgitation has not yet been compared with four-dimensional flow cardiac magnetic resonance imaging.

5p vigamora 23-05-2023 3 2   Download

Magneto-hydro-dynamic generators is a great application to measure the velocity and flow rate for the liquid metal cooled fast breeder reactors because the decrease of working fluid flow caused by the non-uniformity must be immediately identified to initiate reactor processes. In this study, a specific estimation is carried out using the interaction of magnetic field considering the delay of process caused by the eddy current.

6p vidoctorstrange 06-05-2023 9 1   Download

This paper presents the research development on experiments of twophase flow hydrodynamic phenomena at Hanoi University of Science and Technology which include a small-scale test rig in vertical round tube configuration as well as the double-sensor conductivity probe for measuring of local two-phase flow parameters such as void fraction, phasic velocity, interfacial area concentration.

8p visnape 30-01-2023 8 4   Download

(BQ) Ebook Handbook of hydraulics for the solution of hydraulic engineering problems (Seventh edition): Part 1 presents the following content: Chapter 8: open channels with non-uniform flow; chapter 9: high-velocity transitions; chapter 10: wave motion and forces; chapter 11: spatially variable and unsteady flow; chapter 12: measurement of flowing water; chapter 13: advances in hydraulics using computer technology; chapter 14: applicable computer programs.

178p runordie6 10-08-2022 5 1   Download

Drag reduction in fully developed turbulent pipe flow with 4 concentrations (200 to 500 wppm or mg/kg) of low molecular weight sodium carboxymethylcellulose (CMC) in aqueous solutions was investigated experimentally. Drag reduction was determined by pressure drop measurements. Maximum drag reduction achieved was 22% using 500 wppm CMC solution. To observe the impact of the presence of CMC on the flow, ultrasound Doppler velocimetry (UDV) was employed to monitor the instantaneous velocity distributions.

10p langthannam 29-12-2021 7 0   Download

This study addresses, to some extent, the effect of the seeding-particle concentration on the results of spike-excitation UVP measurements. For the investigation, experimental measurements of water pipe flow have been carefully executed for a wide range of the particle concentration. The dependence of the measured data on the particle concentration is evaluated and reported. The result of this study suggests an appropriate range of the seeding-particle concentration in setting up spike-excitation UVP measurements.

12p nguaconbaynhay11 07-04-2021 12 2   Download

Development of knowledge of cardiovascular diseases and treatments strongly depends on understanding of hemodynamic measurements. Hemodynamic parameters, therefore, have been investigated using simulation-based methods.

10p tohitohi 19-05-2020 13 0   Download

In this study, effects of voidage distribution to gas velocity profile in a packed bed with pellet particles was empirically investigated. Uniformity of local velocity at the top of the bed was clearly observed with decreasing of bed height and flow rate. For 400 mm of bed height, the measured velocities are a well fitting to Fahien and Stankovich model for any expected flow rate.

7p abcxyz123_02 03-03-2020 10 0   Download

Canine pyometra is a common disease in bitches, middle-aged to old and dioestrous bitches are frequently affected. In the present study bitches suffering from pyometra show significantly higher resistance Doppler waveform of uterine arteries as compared to cystic endometrial hyperplasia (CEH) and normal dioestrus bitches. In case of dioestrus and CEH groups showed lower blood flow velocities when compared to pyometra groups. Conversely dioestrus and CEH groups show higher hemodynamic indices in comparison to pyometra groups.

5p quenchua2 16-12-2019 7 0   Download

While construction of the Aswan High Dam (AHD) has stopped concurrent flooding events, River Nile is still subject to low intensity flood waves resulting from controlled release of water from the dam reservoir. Analysis of flow released from New Naga-Hammadi Barrage, which is located at 3460 km downstream AHD indicated an increase in magnitude of flood released from the barrage in the past 10 years. A 2D numerical mobile bed model is utilized to investigate the possible morphological changes in the downstream of Naga-Hammadi Barrage from possible higher flood releases.

11p kethamoi1 17-11-2019 33 1   Download

In practice, the location of riverside water intakes is chosen based on land-property considerations rather than strict design criteria. For power plants intakes, abstraction efficiency is directly affected by the uniformity of flow distribution within the intake structure. The intake structure of South Helwan Power Plant (SHPP) is located downstream a Groin Like Formation (GLF) at the right bank of the Nile River, South Cairo, Egypt. This GLF disrupted the uniformity of flow approaching the intake.

9p trinhthamhodang1 14-11-2019 19 1   Download

In this report, we examine the unsteady Stokes equations with nonhomogeneous boundary conditions. As an application of a Carleman estimate, we first establish log type stabilities for the solution of the equations from either an interior measurement of the velocity, or a boundary observation depending on the trace of the velocity and of the Cauchy stress tensor measurements on a part of the boundary.

16p viartemis2711 22-10-2019 11 1   Download

In the present study, flow measurement using particle image velocimetry is implemented to reveal flow features of the RCP model. Velocity and vorticity distributions in the diffuser and spherical casing are obtained. The results illuminate the complexity of the flows in the RCP. Near the lower end of the discharge nozzle, three-dimensional swirling flows and flow separation are evident.

11p minhxaminhyeu3 25-06-2019 16 1   Download

The instantaneous velocity of a bubble is expressed as a function separation distance between the two consecutive bubble nose tips (or the position of the center of the bubble). This experimental technique allows studying and measuring with high accuracy both types of flow: full developed and developing slug flows. The major part of this work (experimental set-up, images digitization) is carried out at Kwangju Institute of Science & Technology (KJIST) in Korea.

10p chikychiky 26-10-2018 18 0   Download

(bq) part 2 book "introduction to fluid mechanics" has contents: drag and lift, dimensional analysis and law of similarity, measurement of flow velocity and flow rate, measurement of flow velocity and flow rate, flow of a compressible fluid, unsteady flow, computational fluid dynamics, computational fluid dynamics.

165p bautroibinhyen19 02-03-2017 61 6   Download

Climate dynamicists generally characterize the Hadley circulation in terms of some derived meteorological parameters, such as the mass stream function (the nondivergent part of the flow) or the velocity potential (the divergent circulation), both of which are based on measurements of the three-dimensional wind field. Yet, we know very little about how such indices have varied in the past—beyond the most recent decades.

512p aries23 29-09-2012 70 12   Download

Tham khảo sách 'specifications tolerances and other technical requirements for weighing and measuring devices', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả

344p khangoc2392 12-08-2012 69 7   Download

Temperature Measurement of Fluids Low Velocity Gas Contact sensors Assume that a gas, with a temperature, T., flows in a tube with a flow-velocity below about 20 m/s, as shown in Figure 17.1(a) . In the tube there is a sheathed sensor, whose sensitive part, at temperature, TT , is placed in the sheath bottom. This case corresponds to a thermocouple with the measuring junction welded into the sheath bottom . Also let the temperature ofthe internal surface ofthe tube wall be TW , while the length to diameter ratio of the sensor sheath is assumed to be so large that...

20p tienvovan 16-09-2010 72 12   Download

Our interest in the measurement of air and water flow is timeless. Knowledge of the direction and velocity of air flow was essential information for all ancient navigators, and the ability to measure water flow was necessary for the fair distribution of water through the aqueducts of such early communities as the Sumerian cities of Ur, Kish, and Mari near the Tigris and Euphrates Rivers around 5,000 B.C. Even today, the distribution of water among the rice patties of Bali is the sacred duty of authorities designated the ÒWater Priests.Ó...

100p thai_ngh 24-06-2010 109 24   Download