scholarly journals Measuring the Continuity of a Gas-Liquid Flow in a Pipeline

2021 ◽  
Vol 2091 (1) ◽  
pp. 012042
Author(s):  
G N Akhobadze
Keyword(s):  
Electromagnetic Wave ◽  
Electric Field ◽  
Liquid Flow ◽  
Isotropic Medium ◽  
Open Resonator ◽  
Measuring Instruments ◽  
Cross Sectional ◽  
Instrument Making ◽  
Study Results ◽  
Gas Liquid Flow

Abstract The principles of building a meter for the continuity of gas-liquid flows in pipelines have been proposed, based on the polarized electromagnetic wave characteristics. A two-component flow in a pipeline has been analyzed considering the cross-sectional area of the flow in the pipeline. The judgment about the flow continuity by the phase difference between the electromagnetic fields polarized parallel and perpendicular to the wave propagation direction has been justified. The naturally and artificially anisotropic flow continuity measuring study results are given. A polarization technique of electromagnetic wave birefringence in the isotropic medium has been considered, based on placing an isotropic medium in an electric field formed by two capacitor electrodes. The possibility of eliminating the parameter measuring errors induced by temperature impact on the electromagnetic wave refractive index in controlled media is shown based on two electrodes of a capacitor creating an electric field in the dielectric pipeline measuring section as an option for implementing flat reflectors of an open resonator. The study results can be used in the instrument-making industry in the development and implementation of smart contactless measuring instruments in the gas-liquid flow analysis and control.

CFD Modelling for Gas-Liquid and Liquid-Liquid Taylor Flows in the Entrance Region of Microchannels

2021 ◽  
Author(s):  
Amin Etminan ◽  
Yuri S. Muzychka ◽  
Kevin Pope
Keyword(s):  
Liquid Flow ◽  
Continuous Flow ◽  
Velocity Ratio ◽  
Time History ◽  
Simulation Method ◽  
Cfd Modelling ◽  
Cross Sectional ◽  
Systematic Analysis ◽  
Gas Liquid Flow ◽  
The Moment

Abstract This paper presents a CFD-based simulation method for air/water and water/dodecane Taylor flows through an axisymmetric microchannel with a circular cross-sectional area. A systematic analysis is conducted by exploring the effects of different superficial velocities and apparent viscosities on the hydrodynamics of a slug flow regime. A concentric junction is employed to make bubbles of air in a continuous flow of water and slugs of water in a continuous flow of dodecane oil. A time-history study is conducted to predict the air-bubble and water-slug evolution processes, in particular at the moment of slug breakup. The results show that the larger apparent viscosity ratio of phases involved in the liquid-liquid flow generates a more stable interface. However, the liquid slug length is less and film thickness is slightly larger in liquid-liquid compared to gas-liquid flow. Furthermore, variations in gas and liquid holdups are correlated by the superficial velocity ratio. The numerical analysis developed in this paper is in good agreement with the correlations and data in the literature.

scholarly journals Comparison of Gas–Liquid Flow Characteristics in Geometrically Different Swirl Generating Devices

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4653 ◽  
Author(s):  
Ryan Anugrah Putra ◽  
Martin Neumann-Kipping ◽  
Thomas Schäfer ◽  
Dirk Lucas
Keyword(s):  
Liquid Flow ◽  
Gamma Ray ◽  
Double Helix ◽  
Flow Characteristics ◽  
Cross Sectional ◽  
Euler Model ◽  
Gas Liquid Flow ◽  
Gas Volume ◽  
Gamma Ray Computed Tomography ◽  
Blade Element

The gas–liquid flow characteristics for blade, single, and the double-helical swirl elements were numerically investigated and compared in this work. The Euler–Euler model assuming bi-modal bubble size distributions was used. The experiment, conducted in a vertical pipe equipped with a static blade swirl element, was used as the basis for the computational fluid dynamics (CFD) simulations. In the experiment, high-resolution gamma-ray computed tomography (HireCT) was used to measure the gas volume fractions at several planes within the blade swirl element. The resulting calculated profiles of the pressure, liquid and gas velocities as well as the gas fraction showed a large influence of the swirl elements’ geometry. The evolution and characteristics of the calculated gas–liquid phase distributions in different measurement planes were found to be unique for each type of swirl element. A single gas core in the center of the pipe was observed from the simulation of the blade element, while multiple cores were observed from the simulations of the single and double helix elements. The cross-sectional gas distribution downstream of the single and double helical elements changed drastically within a relatively short distance downstream of the elements. In contrast, the single gas core downstream of the blade element was more stable.

Modeling the Onset of Gas Entrainment in a Reduced T-Junction With Co-Current Stratified Gas-Liquid Flow

2012 ◽  
Vol 134 (8) ◽  
Author(s):  
Robert C. Bowden ◽  
Ibrahim G. Hassan
Keyword(s):  
Liquid Flow ◽  
Three Dimensional ◽  
Flow Distribution ◽  
Critical Height ◽  
Cross Sectional ◽  
Gas Entrainment ◽  
Mass Fluxes ◽  
Height Prediction ◽  
Dip Angle ◽  
Gas Liquid Flow

A model was developed to predict the onset of gas entrainment in a single downward oriented branch. The branch was installed on a horizontal square cross-sectional channel having a smooth stratified co-currently flowing gas-liquid regime in the inlet region. The branch flow was simulated as a three-dimensional point-sink while the run flow was treated as a uniform velocity at the critical dip. Experiments were performed to determine the critical liquid flow distribution between the run and the branch. A correlation was developed relating the branch Froude number to the ratio of the superficial liquid mass fluxes in the run and the branch. The correlation was used as a boundary condition in the model. A methodology was developed using digital imaging to record the coordinates of the critical dip at the onset of as entrainment. The dip angle was found to range between 40 to 60 degrees and constant dip angles of 40, 50 and 60 degrees were selected as boundary conditions. The critical height was predicted to within 50% of experiments with the error attributed to differences in the modeled and experimental geometries. A semi-empirical analysis using the experimental geometry yielded a critical height prediction to within 20% of experimental results.

ASSESSMENT OF SKILLED BIRTH ATTENDANTS REGARDING HELPING BABIES BREATH INTERVENTION TO IMPROVE NEWBORN CARE IN RURAL DISTRICT OF SINDH

1970 ◽  
Vol 7 (1) ◽  
pp. 48-53
Author(s):  
Sheh Mureed ◽  
Muhammad Hassan Gandro ◽  
Walid Hassan
Keyword(s):  
Newborn Care ◽  
Cross Sectional Study ◽  
Vital Role ◽  
Skilled Birth Attendants ◽  
Cross Sectional ◽  
Neonatal Deaths ◽  
Birth Attendants ◽  
Study Results ◽  
Knowledge And Practice ◽  
Labour Room

Background: Globally, 3.1 million newborn deaths occur every year out of these estimated 400,000 neonatal deaths occur in Pakistan. All neonatal deaths 99% take place in poorest region and countries of the world, usually within hours of birth; mostly the cause of neonatal deaths is hypoxia. To access knowledge and practice of SBAs regarding HBB and to access the availability of equipments required for HBB. Methods: Descriptive Cross-Sectional Study on SBAs as trained in HBB. All 46 SBAs trained on HBB working in Labour room eight rural Health centers, four Taluka, One district Head Quarter Health Facilities and thirteen Mlbcs of the district, were included in the sample for study. All 41 SBAs were trained on HBB participated in the study. Results: Mean age of 30 years. Out of total 41 participants 25 were working in B-EmoNC (61%), 3in C-EmoNC (7.3%) and 13 in mid wife laid birth Centre (MLBC) or birth station (31.7%). About 92.7% of participants said that main purpose of HBB training is to decrease the NMR by improving newborn care. Drying of newborn is 82.7%, hand washing is 95.12% and 85.3% of the study participants said that they gave 30-40 breaths per minutes. Cord clamp and pair of ties was accessible to 85% of participants versus 14.3% who reported it's not accessible. Almost one quarter (34.1%) participants have low knowledge and practice. Knowledge and training had significant effect on the overall practices of the skilled birth attendants for skilled birth deliveries and reduce the neonatal deaths (P <0.001). Conclusion: Tools play a vital role for the implication of the knowledge into practices and tools were available almost to every participant. Although few barriers also identified for the less application of the helping hand babies trainings in the community.

COMPARISION OF DENTAL SCORING SYSTEM WITH RADIOGRAPHIC SKELETAL SYSTEM IN AGE ESTIMATION

JKCD ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 9-11
Author(s):  
Sadaf Ambreen
Keyword(s):  
Age Estimation ◽  
Scoring System ◽  
Skeletal Age ◽  
Chronological Age ◽  
Age Group ◽  
Dental Age ◽  
Scoring Method ◽  
Cross Sectional ◽  
Study Results ◽  
Male Subjects

Objectives: To compare Demirjian Dental scoring method with Greulich-Pyle (GP) Skeletal method of age estimation in pubertal children. Materials and Methods: Sample of the study included 267 male healthy subjects of 11-16 years of age group.. Demirjian Scoring system was utilized to evaluate the orthopantomograms to assess their Dental age and the Hand-Wrist radiographs were analyzed to calculate the skeletal age by utilizing GP atlas. Chronological age was obtained from the date of birth of the subject .Both methods were compared with one another and with the chronological age. It was a cross-sectional study and only healthy male subjects without any clinical abnormalities were included in the study. Results: A total of 267 male subjects of 11-16 years of age group were assessed by Demirjian and Greulich Pyle Methods. Both were compared with Chronological Age. Data obtained was statistically analyzed and the Student “t” test was applied in the study population. The mean difference between Chronolgical age and dental age was 0.69years and that of chronological age and skeletal age was 0.87 years. It was observed from dental age assessment that it does not differ much from the skeletal age. Conclusion: It was concluded that Demirjian method of Age Estimation is more precise than Greulich Pyle method of Age Estimation. Furthermore both methods can be used selectively in Medicolegal cases to access bone age which can be easily correlated to chronological age.

Blood Analysis Requests of Patients’ and Clinical Reflections in Primary Care

2020 ◽  
Vol 9 (2) ◽  
pp. 96-102
Author(s):  
Zerrin Gamsizkan ◽  
Mehmet Ali Sungur ◽  
Yasemin Çayır
Keyword(s):  
Chronic Disease ◽  
Blood Test ◽  
Family Health ◽  
Cross Sectional Study ◽  
Blood Analysis ◽  
Primary Role ◽  
Cross Sectional ◽  
High Expectations ◽  
Blood Tests ◽  
Study Results

Aim: The aim of the study is to determine the factors that may affect the demands of patients who come with the request to have a blood test without any chronic disease or a planned examination check. Methods: The data of this descriptive, cross-sectional study, were collected with a questionnaire that was prepared to examine the opinions of the patients who claim to have a blood test by coming to the family health center without any complaints. Patients over 18 years of age, who did not have any chronic disease and had no scheduled examination appointments were included in the study. Results: A total of 278 patients who wanted to have a blood test within the 6-months period were included in the study. Female patients who wanted to have a blood test were significantly more than male patients. When we look at the causes of patients who wanted to have a blood test; 61.2% (n=170) patients stated that they are concerned about their health and 6.1% (n=17) stated that they were affected by media warnings. There was no significant relationship between the frequency of blood test requests of patients and their age, gender, education, and general health status. Conclusion: Patients with high expectations and anxiety may be more willing to perform blood tests at inappropriate intervals. Family physicians, whose primary role is preventive medicine, have consultancy and information duties in order to protect their patients from the risk of over-examination and diagnosis. Keywords: blood tests, patient, screening, routine diagnostic tests

Vortex Precession in a Gas-Liquid Flow

2010 ◽  
Vol 41 (4) ◽  
pp. 465-478 ◽  
Author(s):  
S. I. Shtork ◽  
Sergei Alekseenko ◽  
V. L. Okulov ◽  
P. A. Kuibin
Keyword(s):  
Liquid Flow ◽  
Vortex Precession ◽  
Gas Liquid Flow
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