Determination of flow rate ratio for plate valve operating in two-phase medium

1989 ◽  
Vol 25 (7) ◽  
pp. 394-396
Author(s):  
V. E. Shcherba ◽  
I. S. Berezin ◽  
S. S. Danilenko ◽  
I. E. Titov ◽  
P. P. Filippov
Keyword(s):  
Flow Rate ◽  
Rate Ratio ◽  
Flow Rate Ratio ◽  
Two Phase ◽  
Plate Valve ◽  
Phase Medium

Slug Formation Analysis of Liquid–Liquid Two-Phase Flow in T-Junction Microchannels

2019 ◽  
Vol 11 (5) ◽  
Author(s):  
Jin-yuan Qian ◽  
Xiao-juan Li ◽  
Zan Wu ◽  
Zhi-jiang Jin ◽  
Junhui Zhang ◽  
...  
Keyword(s):  
Flow Rate ◽  
Rate Ratio ◽  
Two Phase Flow ◽  
Continuous Phase ◽  
Channel Width ◽  
Flow Rate Ratio ◽  
Width Ratio ◽  
Phase Flow ◽  
Channel Depth ◽  
Two Phase

Slug flow is a common flow pattern in the liquid–liquid two-phase flow in microchannels. It is an ideal pattern for mass transfer enhancement. Many factors influence the slug formation such as the channel geometries (channel widths, channel depth), flow rates of the two phase, and physical properties. In this paper, in order to investigate the liquid–liquid two-phase slug formation in a T-junction microchannel quantitatively, the volume of fluid (VOF) method is adopted to simulate the whole slug formation process. With the validated model, the effects of the disperse phase channel width, channel depth, and two-phase flow rate ratio on slug formation frequency and slug size (slug volume and slug length) are analyzed with dimensionless parameters. Dimensionless parameters include the disperse-to-continuous phase channel width ratio, height-to-width ratio, and two-phase flow rate ratio. Results show that both the channel geometry and two-phase flow rate ratio have a significant influence on slug formation. Compared with the conventional slug formation stages, a new stage called the lag stage emerges when the disperse phase channel width decreases to half of the continuous phase channel width. When the channel depth decreases to one third of the continuous phase channel width, the flow patterns become unstable and vary with the two-phase flow rate ratio. Moreover, empirical correlations are proposed to predict the slug formation frequency. The correlation between slug formation frequency and slug volume is quantified.

scholarly journals Determination of Hydraulic Ram Pump Performance: Experimental Results

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Wanchai Asvapoositkul ◽  
Jedsada Juruta ◽  
Nattapong Tabtimhin ◽  
Yosawat Limpongsa
Keyword(s):  
Flow Rate ◽  
Rate Ratio ◽  
Flow Rate Ratio ◽  
Chamber Pressure ◽  
Discharge Flow Rate ◽  
Air Chamber ◽  
Wide Range ◽  
Significant Difference ◽  
Overall Efficiency

The possibility of using a hydraulic ram pump (HRP) as a means of utilizing its energy to produce high head for pump has been investigated. To make such a system economically competitive, it is necessary to improve the performance of HRPs. To achieve this improvement, it is also necessary to understand the parameters that marked out the design of conventional HRPs. The performance is presented in dimensionless terms as the head ratio H∗ or discharge head to drive head and flow-rate ratio Q∗ or discharge flow rate to drive flow rate. The experiments on HRPs were conducted by which each of the following factors could be varied independently: (a) supply head, (b) air chamber pressure, and (c) waste valve beats per minute. An increase in the supply head tends to increase the supply flow rate, delivery flow rate, delivery head, and the overall efficiency of the pump. An increase in air chamber pressure tends to decrease the overall efficiency of the pump. However, there was no significant difference on the HRP performance over a wide range of flow conditions when air chamber pressure was varied. An increase in waste valve beats per minute tends to decrease the supply flow rate, delivery flow rate, and delivery head. But it tends to increase the head ratio, the flow-rate ratio, and the overall efficiency of the pump. The experimental data reveal that the HRP characteristics are functions of the waste valve beats per minute and the supply head.

Continuous generation of alginate microfibers with spindle-knots by using a simple microfluidic device

RSC Advances ◽  
2015 ◽  
Vol 5 (4) ◽  
pp. 2517-2522 ◽  
Author(s):  
Xiaobo Ji ◽  
Song Guo ◽  
Changfeng Zeng ◽  
Chongqing Wang ◽  
Lixiong Zhang
Keyword(s):  
Flow Rate ◽  
Calcium Alginate ◽  
Rate Ratio ◽  
Flow Rate Ratio ◽  
Wet Spinning ◽  
Phase Flow ◽  
Two Phase ◽  
Continuous Generation ◽  
Alginate Microfibers ◽  
Microfluidic Technique

Calcium alginate microfibers with spindle-knots are fabricated by combining microfluidic technique with wet-spinning method. The structures of the knots can be conveniently regulated by changing the two-phase flow rate ratio and the micropipette diameter.

Effect of the argon/monomer flow-rate ratio on the flowability trend of PECVD-processed micropowder

2017 ◽  
Vol 328 ◽  
pp. 480-487 ◽  
Author(s):  
V.R. Giampietro ◽  
M. Gulas ◽  
P. Rudolf von Rohr
Keyword(s):  
Flow Rate ◽  
Rate Ratio ◽  
Flow Rate Ratio

Minimal flow rate ratio of slurry and gas in lime/limestone flue gas scrubbing technology

1992 ◽  
Vol 27 (1) ◽  
pp. 11-15
Author(s):  
H. Voos ◽  
E. Kuciel ◽  
R. Kubisa
Keyword(s):  
Flow Rate ◽  
Flue Gas ◽  
Rate Ratio ◽  
Flow Rate Ratio ◽  
Minimal Flow ◽  
Minimal Flow Rate

scholarly journals Prediction Models of Droplet Characteristics Based on the Locally Convergent Configurations in PMMA Microchips

2021 ◽  
Vol 2097 (1) ◽  
pp. 012027
Author(s):  
Zhongxin Liu ◽  
Zhiliang Wang ◽  
Chao Wang ◽  
Jinsong Zhang
Keyword(s):  
Flow Rate ◽  
Relative Position ◽  
Prediction Models ◽  
Continuous Phase ◽  
Lubricating Oil ◽  
Flow Rate Ratio ◽  
Phase Flow ◽  
Exponential Relationship ◽  
Two Phase ◽  
Relationship Of

Abstract This paper novel designed the local convergence configuration in the coaxial channels to study the two-phase flow (lubricating oil (continuous phase, flow rate Q c)/deionized water (dispersed phase, flow rate Q d)). Two geometric control variables, the relative position (x) and tapering characteristics (α), had the different effects on the droplet formation. The increase of relative position x caused the higher frequency and finer droplets, and the increase of convergence angle α, took the opposite effects. The results indicated that the equivalent dimensionless droplet length Ld/Wout and the flow rate ratio Qd/Qc had an exponential relationship of about 1/2. Similarly, it was found that the dispersed droplets generating frequency and the two-phase capillary number, CaTP = uTPμc/σ, had an exponential relationship. The advantage of the convergent configurations in micro-channel was the size and efficiency of droplet generation was very favorable to be controlled by α and x.

Effects of Respiration and Gravity on Infradiaphragmatic Venous Flow in Normal and Fontan Patients

Circulation ◽  
2000 ◽  
Vol 102 (suppl_3) ◽  
Author(s):  
Tain-Yen Hsia ◽  
Sachin Khambadkone ◽  
Andrew N. Redington ◽  
Francesco Migliavacca ◽  
John E. Deanfield ◽  
...  
Keyword(s):  
Flow Rate ◽  
Rate Ratio ◽  
Venous Return ◽  
Fontan Circulation ◽  
Flow Rate Ratio ◽  
Venous Flow ◽  
Beneficial Effects ◽  
In Series ◽  
Expiratory Flow ◽  
Fontan Patients

Background —In the Fontan circulation, pulmonary and systemic vascular resistances are in series. The implications of this unique arrangement on infradiaphragmatic venous physiology are poorly understood. Methods and Results —We studied the effects of respiration and gravity on infradiaphragmatic venous flows in 20 normal healthy volunteers (control) and 48 Fontan patients (atriopulmonary connection [APC] n=15, total cavopulmonary connection [TCPC] n=30). Hepatic venous (HV), subhepatic inferior vena caval (IVC), and portal venous (PV) flow rates were measured with Doppler ultrasonography during inspiration and expiration in both the supine and upright positions. The inspiratory-to-expiratory flow rate ratio was calculated to reflect the effect of respiration, and the supine-to-upright flow rate ratio was calculated to assess the effect of gravity. HV flow depended heavily on inspiration in TCPC compared with both control and APC subjects (inspiratory-to-expiratory flow rate ratio 3.4, 1.7, and 1.6, respectively; P <0.0001). Normal PV flow was higher in expiration, but this effect was lost in TCPC and APC patients (inspiratory-to-expiratory flow rate ratio 0.8, 1.0, and 1.1, respectively; P =0.01). The respiratory influence on IVC flow was the same in all groups. Gravity decreased HV flow more in APC than in TCPC patients (supine-to-upright flow rate ratio 3.2 versus 2.1, respectively; P <0.04) but reduced PV flow equally in all groups. Conclusions —Gravity and respiration have important influences on infradiaphragmatic venous return in Fontan patients. Although gravity exerts a significant detrimental effect on lower body venous return, which is more marked in APC than in TCPC patients, the beneficial effects of respiration in TCPC patients are mediated primarily by an increase in HV flow. These effects may have important short- and long-term implications for the hemodynamics of the Fontan circulation.

scholarly journals Numerical and experimental investigation on the depressurization capacity of a new type of depressure-dominated jet mill bit

2020 ◽  
Vol 17 (6) ◽  
pp. 1602-1615
Author(s):  
Xu-Yue Chen ◽  
Tong Cao ◽  
Kai-An Yu ◽  
De-Li Gao ◽  
Jin Yang ◽  
...  
Keyword(s):  
Flow Rate ◽  
Rate Ratio ◽  
Area Ratio ◽  
Low Flow ◽  
Flow Rate Ratio ◽  
Cuttings Transport ◽  
Horizontal Drilling ◽  
Hole Cleaning ◽  
Bottom Hole ◽  
New Type

AbstractEfficient cuttings transport and improving rate of penetration (ROP) are two major challenges in horizontal drilling and extended reach drilling. A type of jet mill bit (JMB) may provide an opportunity to catch the two birds with one stone: not only enhancing cuttings transport efficiency but also improving ROP by depressuring at the bottom hole. In this paper, the JMB is further improved and a new type of depressure-dominated JMB is presented; meanwhile, the depressurization capacity of the depressure-dominated JMB is investigated by numerical simulation and experiment. The numerical study shows that low flow-rate ratio helps to enhance the depressurization capacity of the depressure-dominated JMB; for both depressurization and bottom hole cleaning concern, the flow-rate ratio is suggested to be set at approximately 1:1. With all other parameter values being constant, lower dimensionless nozzle-to-throat-area ratio may result in higher depressurization capacity and better bottom hole cleaning, and the optimal dimensionless nozzle-to-throat-area ratio is at approximately 0.15. Experiments also indicate that reducing the dimensionless flow-rate ratio may help to increase the depressurization capacity of the depressure-dominated JMB. This work provides drilling engineers with a promising tool to improve ROP.

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