A Drag Plate Flowmeter for Pulsating Flow

A survey of recent articles shows that drag plate flowmeters, in one form or another, have been about the most popular devices for indicating transient flows. Design principles are given and features discussed, which affect performance in transient or pulsating flow. Where a transient flowmeter has an electrical output it is quîte easy to process the output signal so as to obtain the average flow under pulsating conditions of flow. Thus the drag plate flowmeter is of interest for this important application. Up to the present the transient performance of these flowmeters has been inferred from the examination of the output waveform and from the comparison of the indicated flow with true average flow under pulsating conditions. Details of frequency analysis tests of a drag flowmeter are given.

Download Full-text

Study on Resistance Characteristics of Single-Phase Pulsating Flow in the Horizontal Rectangular Channel

Volume 3: Thermal-Hydraulics; Turbines, Generators, and Auxiliaries ◽

10.1115/icone20-power2012-54257 ◽

2012 ◽

Author(s):

Jing-da Tian ◽

Pu-zhen Gao ◽

Bao Zhou

Keyword(s):

Atmospheric Pressure ◽

Single Phase ◽

Rectangular Channel ◽

Pulsating Flow ◽

Pulsation Period ◽

Resistance Characteristic ◽

Flow Pulsation ◽

Average Flow ◽

Pulsation Amplitude ◽

Inner Diameter

The resistance characteristic of single-phase pulsating flow was experimentally investigated. Using de-ionized water, experiments were conducted in the horizontal rectangular channel with 5.647mm inner diameter, considering three factors that were average flow, pulsation amplitude and pulsation period. Experiments focused on the turbulent region, and the atmospheric pressure and temperature conditions were maintained throughout the experiments. It was found that compared with steady flow in the same channel, the friction coefficient λ under the pulsating conditions was not only affected by the Reynolds number Re, but was also related to pulsation period and pulsation amplitude. And under the pulsating conditions, the Re-λ curve became pulsation circle, it resulted from the acceleration acting on the fluid and the phase difference between Re and λ.

Download Full-text

Average flow generation by a pulsating flow near a curved interface

The European Physical Journal E ◽

10.1140/epje/i2017-11494-7 ◽

2017 ◽

Vol 40 (1) ◽

Cited By ~ 2

Author(s):

Lyudmila S. Klimenko ◽

Dmitry V. Lyubimov

Keyword(s):

Pulsating Flow ◽

Average Flow ◽

Flow Generation ◽

Curved Interface

Download Full-text

Design of Program Controlled Function Signal Generator Based on LPC2138

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.1700 ◽

2014 ◽

Vol 556-562 ◽

pp. 1700-1703

Author(s):

Wan Qian Cheng ◽

Yue Jun Guo ◽

Biao Wang

Keyword(s):

Operational Amplifier ◽

Output Signal ◽

High Speed ◽

Signal Generator ◽

Input Current ◽

Memory Chip ◽

Output Waveform

A design of program controlled function signal generator is introduced. LPC2138 is used as a controller to make the adjustment of frequency, waveform and amplitude programmable. We control the frequency by switching the capacitance and setting the input current of MAX038. We used DS1267 to control the amplitude of output signal with high-speed FET-Input operational amplifier OPA132. Our system is equipped with a keyboard and a LCD screen. We used EEPROM memory chip FM25CL16 to save and load waveform parameters. The circuit works well and the output waveform is stable and reliable.

Download Full-text

On effects of non-systematic reflections on weak-beam images of partial dislocations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087756 ◽

1991 ◽

Vol 49 ◽

pp. 688-689

Author(s):

K. Z. Botros ◽

S. S. Sheinin

Keyword(s):

High Precision ◽

Stacking Fault ◽

Important Application ◽

Stacking Fault Energy ◽

Sharp Peak ◽

Weak Beam ◽

Partial Dislocations ◽

Deviation Parameter ◽

Beam Diffraction

The main features of weak beam images of dislocations were first described by Cockayne et al. using calculations of intensity profiles based on the kinematical and two beam dynamical theories. The feature of weak beam images which is of particular interest in this investigation is that intensity profiles exhibit a sharp peak located at a position very close to the position of the dislocation in the crystal. This property of weak beam images of dislocations has an important application in the determination of stacking fault energy of crystals. This can easily be done since the separation of the partial dislocations bounding a stacking fault ribbon can be measured with high precision, assuming of course that the weak beam relationship between the positions of the image and the dislocation is valid. In order to carry out measurements such as these in practice the specimen must be tilted to "good" weak beam diffraction conditions, which implies utilizing high values of the deviation parameter Sg.

Download Full-text

A peek in the micro-sized world: a review of design principles, engineering tools, and applications of engineered microbial community

Biochemical Society Transactions ◽

10.1042/bst20190172 ◽

2020 ◽

Vol 48 (2) ◽

pp. 399-409

Author(s):

Baizhen Gao ◽

Rushant Sabnis ◽

Tommaso Costantini ◽

Robert Jinkerson ◽

Qing Sun

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Environmental Remediation ◽

Real Life ◽

Design Principles ◽

Microbial Interactions ◽

Potential Applications ◽

New Gene ◽

Global Biogeochemical Cycles ◽

Synthetic Microbial Communities

Microbial communities drive diverse processes that impact nearly everything on this planet, from global biogeochemical cycles to human health. Harnessing the power of these microorganisms could provide solutions to many of the challenges that face society. However, naturally occurring microbial communities are not optimized for anthropogenic use. An emerging area of research is focusing on engineering synthetic microbial communities to carry out predefined functions. Microbial community engineers are applying design principles like top-down and bottom-up approaches to create synthetic microbial communities having a myriad of real-life applications in health care, disease prevention, and environmental remediation. Multiple genetic engineering tools and delivery approaches can be used to ‘knock-in' new gene functions into microbial communities. A systematic study of the microbial interactions, community assembling principles, and engineering tools are necessary for us to understand the microbial community and to better utilize them. Continued analysis and effort are required to further the current and potential applications of synthetic microbial communities.

Download Full-text