Measurements of the Terminal Velocity of Bubbles Rising in a Chain

1973 ◽  
Vol 95 (1) ◽  
pp. 17-22 ◽  
Author(s):  
C. H. Marks
Keyword(s):  
Bubble Size ◽  
Tap Water ◽  
Bubble Radius ◽  
Terminal Velocity ◽  
Bubble Velocity ◽  
Distilled Water ◽  
Rise Velocity ◽  
Sugar Water ◽  
A Chain ◽  
Made In

Measurements were made of the effect of frequency of formation on the velocity of air bubbles rising in a chain through distilled water, lap water, and sugar water. In all cases, increasing the frequency increased the rise velocity for a given bubble size. Measurements made in distilled water showed that the increase of velocity with frequency dropped off with bubble size until it was negligible for the smaller bubbles. It was shown that the variation of bubble velocity with frequency and size can be fairly well correlated with the velocity of rise of solitary bubbles by means of a model based on turbulent wake theory. Tap-water measurements showed the same effect of impurities in the water on the bubble rise velocity as had been observed for solitary bubbles; however, the bubble radius at which the effect became apparent decreased with frequency. Measurements made in sugar water showed that the effect of fluid properties on the rise velocity decreased as frequency increased. At the highest frequencies, no difference could be seen between the distilled water and the sugar water rise velocity curves.

Experimental Study of Bubble-Droplet Interactions in Improved Primary Oil Separation

2019 ◽  
Author(s):  
Joel R. Karp ◽  
Ernesto Mancilla ◽  
Paulo H. D. Santos ◽  
Moisés A. Marcelino Neto ◽  
Rigoberto E. M. Morales
Keyword(s):  
Contact Angle ◽  
Tap Water ◽  
Bubble Radius ◽  
Gas Bubbles ◽  
Terminal Velocity ◽  
Continuous Phase ◽  
Major Influence ◽  
Oil Droplets ◽  
Pure Nitrogen ◽  
Dispersed Phases

Abstract The interactions between dispersed oil droplets and gas bubbles was experimentally studied in this work. An experimental set-up was built in the Multiphase Flow Research Center (NUEM) in the Federal University of Technology – Paraná (UTFPR) to conduct a fundamental evaluation of the interactions between sessile gas bubbles and oil droplets employing side-view flow visualization. Tap water was used as the continuous phase, whereas pure nitrogen and colored vegetable oil were employed as the dispersed phases. The bubble-droplet attachment consisted in the encapsulation of the bubble by the droplet, presenting phenomenological similarities to droplet-droplet coalescence. The contact between the dispersed phases induces the formation of a connecting bridge, which grows rapidly with time, with the height of the bridge being comparable to the size of the droplet after 57.0 ms. The inherent asymmetry of the phenomenon induced a significant horizontal displacement of the bubble towards the droplet, whose position remained unaltered. The evaluation of the bridge meniscus corroborated to this observation, since the contact angle on the droplet side decayed faster with time in comparison to the contact angle on the bubble side. The hydrodynamics of the rising aggregate is also evaluated, by the obtainment of its size, three-dimensional trajectory and terminal velocity. The stable aggregates formed presented an increase factor of 150 to 180%, based on the terminal velocity of the individual droplet. The radius of the bubble was found to be the major influence on the hydrodynamics of the aggregate, allowing the definition of a critical bubble radius based on trajectory instabilities.

Physiochemical properties and reproducibility of air-based sodium tetradecyl sulphate foam using the Tessari method

2016 ◽  
Vol 32 (6) ◽  
pp. 390-396 ◽  
Author(s):  
Mike R Watkins ◽  
Richard J Oliver
Keyword(s):  
Size Distribution ◽  
Bubble Size ◽  
Bubble Size Distribution ◽  
Foam Density ◽  
Physiochemical Properties ◽  
Significant Difference ◽  
Experienced Operator ◽  
Sodium Tetradecyl Sulphate ◽  
Foam Production ◽  
Made In

Objectives The objectives were to examine the density, bubble size distribution and durability of sodium tetradecyl sulphate foam and the consistency of production of foam by a number of different operators using the Tessari method. Methods 1% and 3% sodium tetradecyl sulphate sclerosant foam was produced by an experienced operator and a group of inexperienced operators using either a 1:3 or 1:4 liquid:air ratio and the Tessari method. The foam density, bubble size distribution and foam durability were measured on freshly prepared foam from each operator. Results The foam density measurements were similar for each of the 1:3 preparations and for each of the 1:4 preparations but not affected by the sclerosant concentration. The bubble size for all preparations were very small immediately after preparation but progressively coalesced to become a micro-foam (<250 µm) after the first 30 s up until 2 min. Both the 1% and 3% solution foams developed liquid more rapidly when made in a 1:3 ratio (37 s) than in a 1:4 ratio (45 s) but all combinations took similar times to reach 0.4 ml liquid formation. For all the experiments, there was no statistical significant difference between operators. Conclusions The Tessari method of foam production for sodium tetradecyl sulphate sclerosant is consistent and reproducible even when made by inexperienced operators. The best quality foam with micro bubbles should be used within the first minute after production.

Isothermal Bubble Motion Through a Rotating Liquid

1972 ◽  
Vol 94 (1) ◽  
pp. 187-192 ◽  
Author(s):  
D. L. Schrage ◽  
H. C. Perkins
Keyword(s):  
Radial Direction ◽  
Terminal Velocity ◽  
Distilled Water ◽  
Analytical Prediction ◽  
Bubble Motion ◽  
Large Pressure ◽  
Rotating Liquid ◽  
Angular Velocities ◽  
Large Pressure Gradient ◽  
Good Agreement

An analytical and experimental study of isothermal bubble motion through a liguid which is itself in motion is presented. Both analytical and experimental results are reported for the velocities and trajectories of oxygen bubbles moving through a liquid annulus which is rotating at angular velocities ranging from 500 to 1500 rpm. Results are presented for both distilled water and glycerin. The analytical prediction of the trajectories and velocities showed good agreement with the experimental data. It was found that the bubbles, which were injected at the exterior of the liquid annulus, spiralled inward rapidly and, due to the large pressure gradient in the radial direction, did not reach a constant or terminal velocity.

scholarly journals Designing key parameters of bubble plumes to restore water quality by using conceptual models: a case study in a sub-deep reservoir

2020 ◽  
Vol 20 (7) ◽  
pp. 2915-2927
Author(s):  
Chen Lan ◽  
Jingan Chen ◽  
Jianyang Guo ◽  
Jingfu Wang
Keyword(s):  
Flow Rate ◽  
Bubble Size ◽  
Gas Flow ◽  
Bubble Radius ◽  
Bubble Plume ◽  
Gas Flow Rate ◽  
Empirical Formulas ◽  
Bubble Plumes ◽  
Deep Reservoir ◽  
First Time

Abstract Bubble plumes are a popular hypolimnetic reaeration technique in deep-water reservoirs since they have the advantage of delivering direct reaeration to the hypolimnion. Improving the understanding of the integrated reaeration processes is beneficial to optimize the reaeration capacity of the aeration or oxygenation system. In this study, the discrete bubble model was first employed to design an oxygenation system for a sub-deep reservoir (the Aha Reservoir, southwest China, with water depths of 10–30 m). A new approach involving the discrete bubble model was used to determine the initial bubble size of the bubble plume applied. The intrusion models were demonstrated to be useful for designing the gas flow rate of the reaeration system. Using the intrusion models, we predicted the intrusion thickness and intrusion distance during operation for the first time. Subsequently, we verified the predictions and produced more realistic empirical formulas. At present, reports about recommendations on initial bubble size and gas flow rate are rare, and practical verification is absent. Taking the Aha Reservoir as an example, the initial bubble radius of 1 mm and the gas flow rate of 20 m3·h−1 were recommended for bubble plume oxygenation and were found to be successful in the field. Our understanding of the reaeration processes during the operation of the bubble plume system is far from comprehensive, but this study serves to highlight the potential of the discrete bubble model and the intrusion models for designing a bubble plume system in an individual lake.

Influence of Learning on Taste Preferences

1966 ◽  
Vol 19 (2) ◽  
pp. 445-446 ◽  
Author(s):  
Paul Thomas Young
Keyword(s):  
Tap Water ◽  
Taste Preferences ◽  
Distilled Water

Further discussion of the Schnorr and Brookshire study of the preference between distilled water and tap water, with comments and suggestions.

scholarly journals Hydraulic Conductivity of Compacted Lime-Softening Sludge Used as Landfill Liners

2019 ◽  
Vol 230 (12) ◽  
Author(s):  
Agnieszka Dąbska
Keyword(s):  
Hydraulic Conductivity ◽  
Moisture Content ◽  
Tap Water ◽  
Distilled Water ◽  
Landfill Liners ◽  
Water Permeation ◽  
Lime Softening ◽  
Approximate Polynomial ◽  
Hazardous Waste Landfills

AbstractThe research goal was to investigate the hydraulic conductivity of compacted lime-softening sludge as a material to be applied to landfill liners. In doing so, the effect of compaction and moulding moisture content on the sludge hydraulic conductivity was assessed. An approximate polynomial k10mean at hydraulic gradients ≥30 for degree of compaction (0.95–1.05) and moulding moisture content (28%–36%) was determined. The results of short-term tap water permeation tests revealed that all hydraulic conductivity values were less than 2.5•10–8 m/s. A lowest hydraulic conductivity of 6.5•10–9 m/s, as well as a corresponding moisture content of 31% were then established. The long-term hydraulic conductivity was measured with tap water, distilled water, NaOH and HCl solutions and municipal waste leachate. The factors of permeating liquids and permeation time significantly affected the initial hydraulic conductivity. The long-term hydraulic conductivity increased for NaOH and HCl solutions and decreased for tap and distilled water. A significant reduction of hydraulic conductivity was observed for leachate permeation. The investigated material met the requirements for the liner systems of inert landfill sites regardless of pH and the limit value for hazardous and non-hazardous waste landfills.

Evaluation of Millipore Cartridge-type Water Treatment Systems for Microbiological Applications

1979 ◽  
Vol 42 (8) ◽  
pp. 654-655 ◽  
Author(s):  
BARBARA L. GREEN ◽  
WARREN LITSKY
Keyword(s):  
Water Treatment ◽  
Produced Water ◽  
Tap Water ◽  
Ionic Species ◽  
Distilled Water ◽  
Microbiology Laboratory ◽  
Type Water ◽  
Control Water ◽  
Q System

Two different cartridge-type water treatment systems were evaluated for use in the microbiology laboratory, employing the Distilled Water Suitability Test (DWST). The Milli-Q system fed by distilled water and the Milli-R/Q system fed by tap water both produced water acceptable for microbiological use as measured by the DWST. Concentrations of ionic species (as measured by conductivity) in Milli-Q and Milli-R/Q products were significantly lower than in the double distilled control water.

scholarly journals VII. Re-determination of the mass of a cubic inch of distilled water

1892 ◽  
Vol 183 ◽  
pp. 331-354
Keyword(s):  
Distilled Water ◽  
Weights And Measures ◽  
Made In

The evaluation of the mass of a cubic inch of distilled water, as at present accepted, was based on weighings made in 1798 by Sir G. Shuckburgh ('Phil. Trans.,’ 1798, p. 133); and on measurements made in 1821 by Captain Kater (‘ Phil. Trans.,’ 1821, pp. 316 and 326). Subsequent researches however, particularly those in relation to the mass of a cubic decimetre, show that it is desirable to re-determine the mass of the cubic inch of distilled water. The result of Shuckburgh’s experiments was that the cubic inch of distilled water at the temperature of 66° Fahr., the barometer being at 29·74 inches, weighed 252·422 grains, and this value as corrected by Captain Kater, became 252·458 grains at the temperature of 62° Fahr., the barometer being at 30 inches; or in vacuo ( t . = 62° Fahr.) the cubic inch of distilled water wreighed 252·724 grains. This corrected value, 252·458 grains, has been adopted in various legislative enactments;— for instance the Weights and Measures Act, 5 Geo. IV., c. 74, section 5 (1824), declared that “a cubic inch of distilled water, weighed in air by brass weights, at the temperature of sixty-two degrees of Fahrenheit’s thermometer, the barometer being at thirty inches, is equal to two hundred and fifty-two grains and four hundred and fifty-eight thousandth parts of a grain, of which the imperial standard Troy pound contains five thousand seven hundred and sixty.”

Observations on Hermann of Carinthia's Version of the Elements and its Relation to the Arabic Transmission

2001 ◽  
Vol 14 (1-2) ◽  
pp. 39-84 ◽  
Author(s):  
Sonja Brentjes
Keyword(s):  
Systematic Investigation ◽  
Latin Translation ◽  
Mathematical Work ◽  
Secondary Transmission ◽  
Structural Relevance ◽  
A Chain ◽  
Almost All ◽  
Made In

This paper investigates the affiliation of Book I of the Latin translation of Euclid's Elements attributed to Hermann of Carinthia with the Arabic transmission of the Greek mathematical work. It argues that it is a translation of a text of the Arabic secondary transmission, that is, of an Arabic edition mixed with comments. Two methodological claims are made in the paper. The first insists that the determination of a text whose transmission was as multifaceted and complex as the Euclidean Elements needs to be based on a systematic investigation of entire books rather than on selected theorems or diagrams of global, mostly structural relevance. The second claim starts from the experience that almost all results regarding the place of a particular document in a chain of transmission are conjectural. It acknowledges that individual results are more or less persuasive, depending upon the qualitative status of the argument. It suggests that the quantitative accumulation of similarities, differences, errors, regularities, or peculiarities allows one to recognize patterns and thus improves the reliability of judgment.

Biphasic response to acetylcholine in human veins in vivo: the role of the endothelium

1990 ◽  
Vol 78 (1) ◽  
pp. 101-104 ◽  
Author(s):  
Joe Collier ◽  
Patrick Vallance
Keyword(s):  
Dose Response ◽  
Distilled Water ◽  
Low Doses ◽  
Biphasic Response ◽  
Dorsal Hand ◽  
Before And After ◽  
Higher Doses ◽  
Made In

1. The dose-response to acetylcholine has been examined in dorsal hand veins of healthy volunteers before and after removal of the endothelium. 2. Measurements were made in single dorsal hand veins during local infusions of acetylcholine. The vein was irrigated with distilled water to remove the endothelium. Dilator studies were performed in vessels preconstricted by a continuous infusion of noradrenaline. 3. In the endothelium-intact vessel the dose-response to acetylcholine was biphasic; low doses produced venodilatation with higher doses causing venoconstriction. 4. Dilatation to low doses of acetylcholine was abolished by prior irrigation with distilled water, consistent with denudation of the endothelium by this process. Irrigation augmented the constriction seen in response to higher doses of acetylcholine. 5. This is the first demonstration of an endothelium-dependent biphasic dose-response to acetylcholine in man. The results raise questions as to the possible physiological actions of endogenous acetylcholine and as to the use of the acetylcholine dose-response curve as a marker of endothelial function.

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