978-3-659-47255-8

Ultrasonic flow meters, as all velocity or inference type devices, require an adequate flow stream conditioning in order to assure an accurate performance. Typical flow conditioning consists of straightening the upstream and downstream of the measuring section. The upstream section usually contains a tube bundle, which allows for the upstream section to be reduced in length. This tube bundle serves to eliminate any swirl in the flow stream before reaching the meter, presenting a symmetrical velocity profile to the turbine rotor. Some ultrasonic flow meters may produce a non-uniform pulse output, which can prove a wide span of repeatability. For such cases where is a need to correct the velocity flow profiles which affect the robustness of the integration method, this research work tries to develop a mathematical modeling and simulation in MATLAB and Microsoft Excel, with the purpose to combine the individual acoustic path measurements into a full volumetric flow rate measurement procedure. The relation between velocity and viscosity, using Reynolds Number, was calculated in Microsoft Excel. The Nusselt Number was then used to plot fluid mean temperature and wall temperature diagrams in Microsoft Excel.

2013

Ultrasonic flow meters, as all velocity or inference type devices, require an adequate flow stream conditioning in order to assure an accurate performance. Typical flow conditioning consists of straightening the upstream and downstream of the measuring section. The upstream section usually contains a tube bundle, which allows the upstream section to be reduced in length. This tube bundle serves to eliminate any swirl in the flow stream before reaching the meter, presenting a symmetrical velocity profile to the turbine rotor. Some ultrasonic flow meters may produce a non-uniform pulse output, which can prove a wide span of repeatability. For such cases where is a need to correct the velocity flow profiles which affect the robustness of the integration method, this research work tries to develop a mathematical modeling and simulation in MATLAB and Microsoft Excel, with the purpose to combine the individual acoustic path measurements into a full volumetric flow rate measurement procedu...

2005

2009

Ultrasonic meters can be used for measurement of high viscosity oils. However, in order to do so with high accuracy they have to cope with increased signal attenuation and changing velocity profiles through the transition from turbulent to laminar flow. This paper explains the technical challenges faced when using ultrasonic meters for high viscosity/low Reynolds number flows and shows how

2009

The time of easy recoverable oil is fading away while at the same time the demand for refined products is rising. To meet this demand, oil has to be recovered from fields, such as tar sands, that are much more difficult to explore. Consequently there is also a large increase in the variety of products to be measured as well, including many high viscosity products.

Ultrasonic contrapropagation methods have been used to measure the flow of natural gas since the 1970s, flare gases since the 1980s, and smokestack gases in cem (continuous emissions monitoring) since the 1990s. Since the early 2000s, ultrasonic clamp-on flow measurements, previously restricted mainly to liquids, were found effective in measuring in standard steel pipes, the flow of steam, natural gas and other gases and vapors, including air, as long as the flow velocity was not so high as to cause excessive beam drift or excessive turbulence (in other words, below about Mach 0.1), and provided the acoustic impedance of the gas was equivalent to air above about six bar and no important molecular absorption or scattering mechanisms were present. Although the flow of gases by ultrasonics has long been thought to be more difficult to measure than liquids, in fact the measurement is easier in two important respects. One is, for the contrapropagation method, the upstream -downstream time difference is generally much greater for gases, as a consequence of the much lower sound speeds in gases compared to liquids. The other significant factor that becomes important in mass flow metering (including scfm output) is the existence of theoretical and/or empirical relationships between ultrasonic propagation and density, where either of such relationships is easier to exploit for gases than for liquids. To provide an idea of the scope of applications addressable with ultrasonic technology that is commercially available now or likely to be available in the near future, this paper starts with an analysis from the point of view of acoustic impedance; considers designs as a function of the number of nozzles, from zero to a dozen; and lists factors conducive to high accuracy versus factors detrimental to high accuracy, i.e., conducive to uncertainty.

Energy engineering and control systems, 2021

The article investigated the influence of turbulence parameters of the SolidWorks Flow Simulations CFD package on the results of flow simulation in a two-path ultrasonic flowmeter. It has been found that the main turbulence parameters of SolidWorks Flow Simulations (turbulence intensity, turbulence length, turbulence energy and turbulence dissipation) slightly affect the result of the flow simulation in a full-filled pipeline of circular profile without additional turbulous elements (turbine, rotor, other). In view of this, during the CFD modeling of the flow measurement process using ultrasonic flowmeters, it is recommended to apply turbulence parameters installed in the SolidWorks Flow Simulations CFD package by default. At the same time, the time consumed by the computer to perform CFD modeling is almost unchanged when the specified parameters of the SolidWorks Flow Simulations CFD package.

2015

The present paper describes the CFD numerical simulations of liquid-gas flows in the test rig at Nucleo Experimental de Atalaia (NEAT-PETROBRAS). Results for three flow patterns are presented and discussed: plug flow, slug flow, and stratified wavy flow. In addition, flow pattern transitions were determined based on the CFD results. The simulation results provided relevant information about the flow patterns as well as the transitions between them. Except for the annular flow, which presents several difficulties for simulation, the flow pattern predictions in the simulations agree with the predictions made using the Baker flow pattern map. Furthermore, the CFD simulations allowed for reliable, time dependent GVF results, which can be used for direct comparison with the acoustic signals from the multiphase flow meter. The CFD simulations described herein thus provide the necessary means for calibration of the ultrasonic multiphase flow meter being developed.

Capitolul unu Eram mai mare decât toate prietenele mele când mi-am făcut primul tatuaj. Mamei îi place la nebunie să spună povestea aceea. Mi-aș dori să no facă. Când împlinești două zile, ar trebui să primești un semn din naștere, însă în loc de asta eu m-am îmbolnăvit, așa că mama a anulat ceremonia. Prietenele mamei i-au spus:-Sophie, trebuie să-i faci un semn. Ce nume ai de gând să-i pui? Însă mama le-a zis că va aștepta până ce mă voi însănătoși. După aceea voi primi un nume și un tatuaj. Le-a ignorat avertismentele spuse în șoaptă în legătură cu ce li se întâmplă bebelușilor care mor neînsemnați. Și astfel, timp de douăzeci de zile am rămas goală și fără formă, până ce într-o zi mama a spus:-O so cheme Leora. Și Leora a fost. Cuvântul mi-a fost trasat în carne cu ace minuscule. Niște litere mititele care au crescut împreună cu mine timp de șaisprezece ani. Nu ne e frică de moarte. Când semnele îți sunt în siguranță în carte, continui să trăiești și după ce mori. Povestea vieții tale, întipărită pe trup, e păstrată pentru totdeauna-dacă ești vrednic. Când păstrăm cuvinte, imagini și momente imprimate pe piele, povestea noastră supraviețuiește pentru eternitate. Suntem înconjurați de morți și, cât timp cărțile lor sunt citite încă și câtă vreme se mai vorbește de numele lor, ei trăiesc. Fiecare are cărți de piele acasă: rafturile noastre de acasă sunt pline cu strămoșii mei. Le pot simți mirosul, îi pot atinge și pot citi despre viețile lor. Însă abia după ce a murit tatăl meu am văzut cartea cuiva pe care îl cunoșteam cu adevărat. * * * Eram norocoși, într-adevăr, pentru că vedeam moartea apropiindu-se de la distanță. Asta însemna că puteam fi pregătiți. Îi masam pielea cu ulei; el ne spunea poveștile tatuajelor sale și zâmbea când ne arăta copacul de pe spate cu numele noastre pe el. Era pregătit atunci când s-a dus, și la fel era și pielea lui. Am văzut cum brațele lui puternice se scofâlcesc, lăsându-i pielea zbârcită ca un măr veșted. I-am văzut spatele drept încovoindu-se, de parcă ar fi fost lovit în stomac. După o vreme, a încetat să ne mai privească direct; nu vedea decât durerea. Se părea că boala îl absorbise în totalitate, lăsându-i doar învelișul, însă învelișul e ceea ce contează. Oamenii ne-au adus flori și mâncare pentru a face acele ultime zile mai ușoare. Mici dovezi de iubire pentru tata, atunci când nu mai puteau face nimic altceva. Nu eram singurele ale căror inimi erau frânte; tata era atât de iubit de așa VP-3 VP-50