scholarly journals High accuracy volume flow rate measurement using vortex counting

2013 ◽  
Vol 33 ◽  
pp. 138-144 ◽  
Author(s):  
A. Zaaraoui ◽  
F. Ravelet ◽  
F. Margnat ◽  
S. Khelladi
Keyword(s):  
Flow Rate ◽  
Volume Flow Rate ◽  
High Accuracy ◽  
Volume Flow ◽  
Rate Measurement ◽  
Flow Rate Measurement

Traceable Flow Rate Measurements With a Very Low Uncertainty Using Laser Doppler Anemometry

2017 ◽  
Author(s):  
Markus Juling ◽  
Jonas Steinbock ◽  
Andreas Weissenbrunner
Keyword(s):  
Flow Rate ◽  
Laser Doppler Anemometry ◽  
Volume Flow Rate ◽  
Primary Standard ◽  
Volume Flow ◽  
Laser Doppler ◽  
Maximum Deviation ◽  
Flow Profile ◽  
Rate Measurement ◽  
Flow Rate Measurement

Precise volume flow rate measurements are very important for various industrial applications. Here, one problem is that the service conditions of a flow meter used in the field differ significantly from the conditions present during calibration. The working conditions such as the pressure, the temperature and the flow profile greatly increase the uncertainty of the flow rate measurement. To address this problem, a new laser-optical flow rate standard (LFS) was developed at the Physikalisch-Technische Bundesanstalt (PTB) that allows flow meters to be calibrated on site, thus greatly reducing the uncertainty of the flow rate measurement. For the LFS, the velocity profile within the pipe is measured with laser Doppler anemometry (LDA). The profile is then integrated to calculate the volume flow rate. Various improvements to LDA have made it possible to measure the flow rate with an uncertainty of less than 0.15 % (k = 2). A comparison of the LFS with the primary standard for thermal energy at PTB, which has an uncertainty of less than 0.04 % (k = 2), revealed a maximum deviation of 0.07 % for Reynolds numbers from 105 to 106, thus verifying the uncertainty of the LFS.

Electrostatic Sensor for Real–Time Mass Flow Rate Measurement of Particle Conveying in Pneumatic Pipeline

2012 ◽  
Author(s):  
Mohd. Fua’ad Rahmat ◽  
Wee Lee Yaw
Keyword(s):  
Real Time ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Cross Correlation ◽  
High Accuracy ◽  
Industrial Processes ◽  
Rate Measurement ◽  
Flow Rate Measurement ◽  
Controlled Flow

This paper discussed the electrostatic sensors that have been constructed for real–time mass flow rate measurement of particle conveying in a Pneumatic pipeline. Many industrial processes require continuous, smooth, and consistent delivery of solids materials with a high accuracy of controlled flow rate. This requirement can only be achieved by installing a proper measurement system. Electrostatic sensor offers the most inexpensive and simplest means of measuring solids flows in pipes. Key words: Electrostatic sensor, cross-correlation, peripheral velocity

scholarly journals Акустический расходомер

2019 ◽  
Vol 89 (9) ◽  
pp. 1434
Author(s):  
В.А. Бузановский
Keyword(s):  
Relative Error ◽  
Flow Rate ◽  
High Speed ◽  
Volume Flow Rate ◽  
High Accuracy ◽  
Volume Flow ◽  
Metrological Characteristics ◽  
Simple Design ◽  
Liquid Substance

The design and metrological characteristics of the acoustic flowmeter of a flow of a gaseous or liquid substance are considered. It is shown that the device has a simple design, is characterized by high accuracy (relative error of measuring the volume flow rate is less than 1%) and high speed (the time to determine the flow rate is not more than a few milliseconds).

High-Accuracy Flow Rate Measurement using Lamb Waves in Clamp-On Type Ultrasonic Flowmeter

2000 ◽  
Vol 2000.1 (0) ◽  
pp. 895-896
Author(s):  
Tomomi NISHI ◽  
Yoshiaki TANAKA ◽  
Yumiko SUGIYAMA ◽  
Satoshi FUKUHARA
Keyword(s):  
Flow Rate ◽  
Lamb Waves ◽  
High Accuracy ◽  
Ultrasonic Flowmeter ◽  
Rate Measurement ◽  
Flow Rate Measurement

Indirect measurement of the flow rate based upon a solution of an inverse coefficient problem

2018 ◽  
Vol 28 (1) ◽  
pp. 92-102 ◽  
Author(s):  
Kazimierz Rup ◽  
Lukasz Malinowski ◽  
Piotr Sarna
Keyword(s):  
Fluid Flow ◽  
Flow Rate ◽  
Indirect Method ◽  
Measuring Method ◽  
High Accuracy ◽  
Fluid Flow Rate ◽  
Rate Measurement ◽  
Flow Rate Measurement ◽  
Flow Meter ◽  
Content Type

Purpose The purpose of this paper is to extend the possibilities of using the earlier developed indirect method of fluid flow rate measurement in circular pipes to the square-section channels with elbows installed. Design/methodology/approach The idea of the method is based on selecting such a value of the Reynolds number assumed as a coefficient in fluid flow equations, which fulfills with set accuracy the condition of equality between the measured and computed pressure difference at the end points of the secant of the elbow arch. The numerical calculus takes into consideration the exact geometry of the flow space and the measured temperature of the fluid, on the basis of which its thermo–physical properties are determined. To implement the proposed method in practice, a special test stand was built. The numerical computations were carried out using the software package FLUENT. Findings The results of calculations were compared with corresponding results of measurements achieved on the stand, as well as those found in the literature. The comparative analysis of the obtained numerical and experimental results shows a high grade of consistence. Practical implications The discussed elbow flow meter, implementing the extended indirect measuring method, can be applied to determine the flow rate of gases, as well as liquids and suspensions. Originality/value The indirect method used to measure the volumetric flow rate of the fluid is characterized by high accuracy and repeatability. The high accuracy is possible because of a very realistic mathematical model of the complex flow in the curved duct. The indirect method eliminates the necessity of frequent calibration of the flow meter. The discussed extended indirect measuring method can be applied to determine the flow rate of gases as well as liquids and suspensions. The fluid flow rate measurement based on the method considered in this paper can be particularly useful in newly designed as well as already operated ducts.

Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

1989 ◽  
Vol 47 ◽  
pp. 1000-1001
Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby
Keyword(s):  
Electron Microscopy ◽  
Flow Rate ◽  
Succinic Anhydride ◽  
Volume Flow Rate ◽  
Mass Density ◽  
Uranyl Acetate ◽  
Volume Flow ◽  
Base Resin ◽  
And Performance ◽  
Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

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