Measurement of droplet size for wide range particle distributions

AIAA Journal ◽  
1964 ◽  
Vol 2 (3) ◽  
pp. 583-585 ◽  
Author(s):  
J. H. ROBERTS ◽  
M. J. WEBB
Keyword(s):  
Droplet Size ◽  
Particle Distributions ◽  
Wide Range

Nanoemulsions: A Versatile Technology for Oil and Gas Applications

2021 ◽  
Author(s):  
Nouf AlJabri ◽  
Nan Shi
Keyword(s):  
Droplet Size ◽  
Large Scale ◽  
Oil And Gas ◽  
Volume Fraction ◽  
Oil Industry ◽  
Oil And Gas Industry ◽  
High Energy ◽  
Small Droplet ◽  
Gas Industry ◽  
Wide Range

Abstract Nanoemulsions (NEs) are kinetically stable emulsions with droplet size on the order of 100 nm. Many unique properties of NEs, such as stability and rheology, have attracted considerable attention in the oil industry. Here, we review applications and studies of NEs for major upstream operations, highlighting useful properties of NEs, synthesis to render these properties, and techniques to characterize them. We identify specific challenges associated with large-scale applications of NEs and directions for future studies. We first summarize useful and unique properties of NEs, mostly arising from the small droplet size. Then, we compare different methods to prepare NEs based on the magnitude of input energy, i.e., low-energy and high-energy methods. In addition, we review techniques to characterize properties of NEs, such as droplet size, volume fraction of the dispersed phase, and viscosity. Furthermore, we discuss specific applications of NEs in four areas of upstream operations, i.e., enhanced oil recovery, drilling/completion, flow assurance, and stimulation. Finally, we identify challenges to economically tailor NEs with desired properties for large-scale upstream applications and propose possible solutions to some of these challenges. NEs are kinetically stable due to their small droplet size (submicron to 100 nm). Within this size range, the rate of major destabilizing mechanisms, such as coalescence, flocculation, and Ostwald ripening, is considerably slowed down. In addition, small droplet size yields large surface-to-volume ratio, optical transparency, high diffusivity, and controllable rheology. Similar to applications in other fields (food industry, pharmaceuticals, cosmetics, etc.), the oil and gas industry can also benefit from these useful properties of NEs. Proposed functions of NEs include delivering chemicals, conditioning wellbore/reservoir conditions, and improve chemical compatibility. Therefore, we envision NEs as a versatile technology that can be applied in a variety of upstream operations. Upstream operations often target a wide range of physical and chemical conditions and are operated at different time scales. More importantly, these operations typically consume a large amount of materials. These facts not only suggest efforts to rationally engineer properties of NEs in upstream applications, but also manifest the importance to economically optimize such efforts for large-scale operations. We summarize studies and applications of NEs in upstream operations in the oil and gas industry. We review useful properties of NEs that benefit upstream applications as well as techniques to synthesize and characterize NEs. More importantly, we identify challenges and opportunities in engineering NEs for large-scale operations in different upstream applications. This work not only focuses on scientific aspects of synthesizing NEs with desired properties but also emphasizes engineering and economic consideration that is important in the oil industry.

scholarly journals Development of Drift-Reducing Spouts For Vineyard Pneumatic Sprayers: Measurement of Droplet Size Spectra Generated and Their Classification

2020 ◽  
Vol 10 (21) ◽  
pp. 7826
Author(s):  
Marco Grella ◽  
Antonio Miranda-Fuentes ◽  
Paolo Marucco ◽  
Paolo Balsari ◽  
Fabrizio Gioelli
Keyword(s):  
Droplet Size ◽  
Marked Reduction ◽  
Reduction Potential ◽  
Liquid Flow Rate ◽  
Spray Drift ◽  
Spray Application ◽  
Size Spectra ◽  
Wide Range ◽  
Environmental Requirements ◽  
Low Drift

Pneumatic spraying is especially sensitive to spray drift due to the production of small droplets that can be easily blown away from the treated field by the wind. Two prototypes of environmentally friendly pneumatic spouts were developed. The present work aims to check the effect of the spout modifications on the spray quality, to test the convenience of setting the liquid hose out of the spout in cannon-type and hand-type pneumatic nozzles and its effect on the droplet size, homogeneity and driftability in laboratory conditions. Laboratory trials simulating a real sprayer were conducted to test the influence of the hose insertion position (HP), including conventional (CP), alternative (AP), outer (OP) and extreme (XP), as well as the liquid flow rate (LFR) and the airflow speed (AS) on the droplet size (D50, D10 and D90), homogeneity and driftability (V100). Concurrently, the droplet size spectra obtained by the combination of aforementioned parameters (HP × LFR × AS) in both nozzles were also classified according to the ASABE S572.1. Results showed a marked reduction of AS outside the air spout, which led to droplet size increase. This hypothesis was confirmed by the droplet size spectra measured (D50, D10, D90 and V100). A clear influence of HP was found on every dependent variable, including those related with the droplet size. In both nozzles, the longer the distance to CP, the coarser the sprayed drops. Moreover, LFR and AS significantly increased and reduced droplet size, respectively. A higher heterogeneity in the generated drops was obtained in XP. This position yielded V100 values similar to those of the hydraulic low-drift nozzles, showing an effective drift reduction potential. The classification underlines that the variation of HP, alongside AS and LFR, allowed varying the spray quality from very fine to coarse/very coarse, providing farmers with a wide range of options to match the drift-reducing environmental requirements and the treatment specifications for every spray application.

Centrifugal injector droplet size over a wide range of dispersant properties

1973 ◽  
Vol 5 (3) ◽  
pp. 492-499
Author(s):  
M. K. Baranaev ◽  
V. I. Tenyakov
Keyword(s):  
Droplet Size ◽  
Wide Range ◽  
Centrifugal Injector

scholarly journals Surfactant-Free Cellulose Filaments Stabilized Oil in Water Emulsions

2021 ◽  
Author(s):  
Amir Varamesh ◽  
Ragesh Prathapan ◽  
Ali Telmadarreie ◽  
Jia Li ◽  
Keith Gourlay ◽  
...  
Keyword(s):  
Droplet Size ◽  
Fluorescent Protein ◽  
Fluorescent Microscopy ◽  
Cellulose Nanofibrils ◽  
Continuous Phase ◽  
Carbohydrate Binding ◽  
Pickering Emulsions ◽  
Cellulosic Material ◽  
Oil In Water ◽  
Wide Range

Abstract There has been significant interest over recent years in the production and application of sustainable and green materials. Among these, nanocellulose has incurred great interest because of its exceptional properties and wide range of potential applications, including in Pickering emulsions. However, the production cost of these cellulosic materials has limited their application. In this study, the capability of a new type of cheaper cellulosic material, cellulose filaments (CFs), in formulating stable oil in water Pickering emulsions was investigated and compared with three conventional nanocelluloses, namely cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs) and TEMPO-oxidized CNFs (TEMPO-CNFs). Results showed that CFs can provide stable surfactant-free emulsions over wide ranges of salt concentration (0 – 500 mM) and pH (2 – 10), as indicated by the near constant oil droplet size and dewatering index of the emulsions. This is due to the ability of CFs to strongly adsorb to the oil and water interface, as evidenced by visualizing labeled CFs with engineered carbohydrate-binding module (CBM2a) conjugated with green fluorescent protein (CBM2a-eGFP) under fluorescent microscopy. Compared to the emulsions stabilized by other types of nanocelluloses, the CFs-stabilized emulsion demonstrated a larger average droplet size and comparable (with CNFs) or better (than CNCs and TEMPO-CNFs) stability, which is partially attributed to the higher viscosity of continuous phase in the presence of CFs. The results of this study demonstrate the use of CFs as a novel and cheaper cellulosic material for stabilizing emulsions, which opens the door to a range of markets from the food industry to engineering applications.

scholarly journals Precise detection of the size of monodisperse droplets considering the fluctuations induced by the droplet generation process

2021 ◽  
Author(s):  
Wen Zeng ◽  
Hai Fu
Keyword(s):  
Droplet Size ◽  
Detection Method ◽  
Droplet Microfluidics ◽  
Generation Process ◽  
Time Varying ◽  
Electrical Detection ◽  
Flow Focusing ◽  
Wide Range ◽  
Droplet Production ◽  
Monodisperse Droplets

Abstract For droplet microfluidics, the electrical-detection method which can precisely detect the size of monodisperse droplets is demonstrated in this paper. In a Flow-focusing microdroplet generator, three pairs of the microelectrodes are allocated along the microchannel, and during the passing-by process of each droplet, both the length, the velocity and the production speed of the droplets can be obtained from the experimental measurements of the time-varying capacitance between each pair of the microelectrodes. Particularly, for different geometries of the Flow-focusing microchannel, the method of the electrical-detection is validated experimentally over a wide range of the typical conditions of monodisperse droplet production. In addition, the droplet size measured by the electrical-detection method is compared with that by the method of image processing, and the detection precision of the electrical-detection method is verified experimentally. Most importantly, by calculating the root-mean-square value of the droplet lengths for three pairs of the microelectrodes, the detection precision of the droplet size can be increased drastically.

Effect of Water Temperature on the Performance of Gas Turbine Inlet Air-Fogging Systems

2013 ◽  
Author(s):  
Mustapha A. Chaker ◽  
Cyrus B. Meher-Homji
Keyword(s):  
Water Temperature ◽  
Gas Turbine ◽  
Droplet Size ◽  
Gas Turbines ◽  
Cold Water ◽  
Hot Water ◽  
Initial Water ◽  
Effect Of Water ◽  
Turbine Inlet ◽  
Wide Range

With more than 1000 fogging systems installed worldwide on a wide range of gas turbines of different types, gas turbine inlet air fogging systems have become a well-established technology used to increase gas turbines power output. The major benefit of spraying fog droplets in the inlet airflow of the gas turbines is to increase the density of the air entering the gas turbine by evaporative cooling in the inlet air stream. Significant amount of research has been carried out to improve the efficiency of fogging systems. However, the effect of water temperature on the overall efficiency of a fogging system has yet to be addressed. In this paper, a detailed analysis of this effect will be presented, both from an experimental and a theoretical view point. Due to the small size of the droplets used in this application, the temperature of the droplet converges quickly to the wet bulb temperature, regardless of the initial water temperature. The rapidity at which this convergence occurs depends on the initial droplet size, the water temperature, the air mass flow to mass of injected water ratio, and the ambient psychrometric conditions of the surrounding air. The present study was carried out using water temperatures between 1 °C and 60 °C. Results showed that the water temperature has no significant effect on the droplet size. However, within the range of droplet sizes atomized from nozzles installed in the fogging system, using cold water provides a marginal benefit on the cooling efficiency; using hot water, on the other hand, slightly increases the evaporation efficiency.

The application of filtration theory to food gathering in Ordovician crinoids

2007 ◽  
Vol 81 (6) ◽  
pp. 1284-1300 ◽  
Author(s):  
James C. Brower
Keyword(s):  
Behavioral Changes ◽  
Filtration Theory ◽  
Upper Ordovician ◽  
Nutrient Contents ◽  
Particle Distributions ◽  
Wide Range ◽  
Ecological Patterns ◽  
Food Particles ◽  
Mean Size ◽  
Tube Feet

Food gathering of some adult Upper Ordovician crinoids was modeled by means of filtration theory. The arm-branching patterns of the 13 species examined range from nonpinnulate isotomous arms to uniserial and biserial arms with numerous pinnules. Most taxa are roughly equivalent with respect to ambient current velocities and the nutrient contents needed from seawater. Two species with extensively branched arms have markedly higher nutritional requirements at any one ambient current velocity. The results are somewhat correlated with environment in the form of differential current velocities, water flow patterns, and food abundance and composition. The data are generally compatible with filtration theory and the environmental distributions of many Ordovician and other Paleozoic crinoids, and they reveal that Upper Ordovician crinoids had at least partially developed the ecological patterns seen in later Paleozoic crinoids. Various morphological, physiological, and behavioral changes can be employed by crinoids to alter their nutritional balance. The size distributions of food particles that are caught by the crinoids are modeled. These food particle distributions for the Ordovician fossils resemble those of modern crinoids. Relative to the population of food items, the distributions of particles that are trapped are shifted towards larger items because the crinoid filtration nets are more efficient at catching larger particles. Crinoids with relatively open filtration nets and large food-catching tube feet are generalized and feed on a wide range of food particles of a relatively large mean size. The more specialized taxa with extensively branched arms bearing small and closely packed food-catching tube feet are restricted to a more narrow range of smaller food particles.

Comparing Simulation for Turbulent Dispersion and Coalescence of Droplets within a Spray with Two Models

2013 ◽  
Vol 353-356 ◽  
pp. 2473-2476
Author(s):  
Shao Yun Deng
Keyword(s):  
Droplet Size ◽  
Droplet Size Distribution ◽  
Computer Time ◽  
Turbulent Dispersion ◽  
Gas Flows ◽  
Wide Range ◽  
Order Of Magnitude ◽  
Time Required ◽  
And Shifts ◽  
Droplet Size Distributions

Lagrangian and Eulerian modelling approaches are compared for simulating turbulent dispersion and coalescence of droplets within a spray. Both models predict similar droplet dispersion rates and shifts in droplet size distribution due to coalescence within the spray, over a wide range of droplet and gas flows, and for sprays with different droplet size distributions at the nozzle exit. The computer time required for simulating coalescence within a steady axisymmetric spray is of a similar order of magnitude regardless of which formulation, Eulerian or Lagrangian, is adopted. However, the Lagrangian formulation is more practical in terms of the range of applicability and ease of implementation.

The Combustion of Droplets Within Gas Turbine Combustors Some Recent Observations on Combustion Efficiency

1992 ◽  
Author(s):  
J. Odgers ◽  
D. Kretschmer ◽  
G. F. Pearce
Keyword(s):  
Experimental Data ◽  
Droplet Size ◽  
Gas Turbines ◽  
Research Laboratory ◽  
Combustion Efficiency ◽  
Operating Conditions ◽  
Transfer Number ◽  
Wide Range ◽  
Inlet Conditions ◽  
Experimental Values

For many years investigators studying the combustion behaviour within gas turbines have presumed droplet size to play a very important role in defining combustion efficiency. Recently a very large number of experiments have been conducted jointly by Laval University and the Aeronautical Research Laboratory in Melbourne. In the course of these investigations, over a wide range of operating conditions, a single combustor has been investigated using three different Simplex atomisers at each of the conditions for three fuels. In addition, the same combustor has been used to investigate a very wide range of fuels (87) at ambient inlet conditions. The measured combustion efficiencies show no measurable effects due to droplet size, although volatility effects have been noted (measured as TAV). It is thought that these effects are reflected in terms of a Transfer Number and related to diffusional phenomena, rather than evaporative phenomena. A great number of experimental data are reviewed, and in addition to showing the absence of effects of droplets, a small section deals with the precision of experimental values of combustion efficiency and how it might influence models predicting combustion efficiency, especially with respect to possible future pollution requirements.

The Combustion of Droplets Within Gas Turbine Combustors: Some Recent Observations on Combustion Efficiency

1993 ◽  
Vol 115 (3) ◽  
pp. 522-532 ◽  
Author(s):  
J. Odgers ◽  
D. Kretschmer ◽  
G. F. Pearce
Keyword(s):  
Experimental Data ◽  
Droplet Size ◽  
Gas Turbines ◽  
Research Laboratory ◽  
Combustion Efficiency ◽  
Operating Conditions ◽  
Transfer Number ◽  
Wide Range ◽  
Inlet Conditions ◽  
Experimental Values

For many years investigators studying the combustion behavior within gas turbines have presumed droplet size to play a very important role in defining combustion efficiency. Recently a very large number of experiments have been conducted jointly by Laval University and the Aeronautical Research Laboratory in Melbourne. In the course of these investigations, over a wide range of operating conditions, a single combustor has been investigated using three different Simplex atomizers at each of the conditions for three fuels. In addition, the same combustor has been used to investigate a very wide range of fuels (87) at ambient inlet conditions. The measured combustion efficiencies show no measurable effects due to droplet size, although volatility effects have been noted (measured as TAV). It is thought that these effects are reflected in terms of a transfer number and related to diffusional phenomena, rather than evaporative phenomena. A great number of experimental data are reviewed, and in addition to showing the absence of effects of droplets, a small section deals with the precision of experimental values of combustion efficiency and how it might influence models predicting combustion efficiency, especially with respect to possible future pollution requirements.

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