On the Impact of Liquid Drops on Immiscible Liquids

2016 ◽  
Author(s):  
Eduardo Castillo-Orozco ◽  
Ashkan Davanlou ◽  
Pretam K. Choudhury ◽  
Ranganathan Kumar
Keyword(s):  
Oil Spills ◽  
Silicone Oil ◽  
Density Ratio ◽  
High Viscosity ◽  
Impact Behavior ◽  
Immiscible Fluid ◽  
Liquid Droplets ◽  
Liquid Drops ◽  
Low Viscosity ◽  
The Impact

The release of liquid hydrocarbons into the water is one of the environmental issues that have attracted more attention after deepwater horizon oil spill in Gulf of Mexico. The understanding of the interaction between liquid droplets impacting on an immiscible fluid is important for cleaning up oil spills as well as the demulsification process. Here we study the impact of low-viscosity liquid drops on high-viscosity liquid pools, e.g. water and ethanol droplets on a silicone oil 10cSt bath. We use an ultrafast camera and image processing to provide a detailed description of the impact phenomenon. Our observations suggest that viscosity and density ratio of the two media play a major role in the post-impact behavior. When the droplet density is larger than that of the pool, additional cavity is generated inside the pool. However, if the density of the droplet is lower than the pool, droplet momentary penetration may be facilitated by high impact velocities. In crown splash regime, the pool properties as well as drop properties play an important role. In addition, the appearance of the central jet is highly affected by the properties of the impacting droplet. In general, the size of generated daughter droplets as well as the thickness of the jet is reduced compared to the impact of droplets with the pool of an identical fluid.

Experiments on the breakup of drop-impact crowns by Marangoni holes

2018 ◽  
Vol 844 ◽  
pp. 162-186 ◽  
Author(s):  
Abdulrahman B. Aljedaani ◽  
Chunliang Wang ◽  
Aditya Jetly ◽  
S. T. Thoroddsen
Keyword(s):  
Surface Tension ◽  
Lower Surface ◽  
High Viscosity ◽  
Solid Substrate ◽  
Immiscible Liquid ◽  
Hole Formation ◽  
Low Viscosity ◽  
Stress Changes ◽  
Lower Surface Tension ◽  
The Impact

We investigate experimentally the breakup of the Edgerton crown due to Marangoni instability when a highly viscous drop impacts on a thin film of lower-viscosity liquid, which also has different surface tension than the drop liquid. The presence of this low-viscosity film modifies the boundary condition, giving effective slip to the drop along the solid substrate. This allows the high-viscosity drop to form a regular bowl-shaped crown, which rises vertically away from the solid and subsequently breaks up through the formation of a multitude of Marangoni holes. Previous experiments have proposed that the breakup of the crown results from a spray of fine droplets ejected from the thin low-viscosity film on the solid, e.g. Thoroddsen et al. (J. Fluid Mech., vol. 557, 2006, pp. 63–72). These droplets can hit the inner side of the crown forming spots with lower surface tension, which drives a thinning patch leading to the hole formation. We test the validity of this assumption with close-up imaging to identify individual spray droplets, to show how they hit the crown and their lower surface tension drive the hole formation. The experiments indicate that every Marangoni-driven patch/hole is promoted by the impact of such a microdroplet. Surprisingly, in experiments with pools of higher surface tension, we also see hole formation. Here the Marangoni stress changes direction and the hole formation looks qualitatively different, with holes and ruptures forming in a repeatable fashion at the centre of each spray droplet impact. Impacts onto films of the same liquid, or onto an immiscible liquid, do not in general form holes. We furthermore characterize the effects of drop viscosity and substrate-film thickness on the overall evolution of the crown. We also measure the three characteristic velocities associated with the hole formation: i.e. the Marangoni-driven growth of the thinning patches, the rupture speed of the resulting thin films inside these patches and finally the growth rate of the fully formed holes in the crown wall.

scholarly journals Analysis of Cryogenic Impact Properties for a Glass-Fiber-Reinforced Dicyclopentadiene with a Different Amount of Decelerator Solution

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3246
Author(s):  
Ji Ho Jeon ◽  
Woo Il Lee ◽  
Jong Min Choi ◽  
Sung Woong Choi
Keyword(s):  
Glass Fiber ◽  
Weight Fraction ◽  
Expansion Ratio ◽  
Impact Behavior ◽  
Fiber Reinforced ◽  
Impact Properties ◽  
Chemical Corrosion ◽  
Low Viscosity ◽  
Glass Fiber Reinforced ◽  
The Impact

Composites using dicyclopentadiene (DCPD) as a matrix have gained significant popularity owing to their excellent impact and chemical corrosion resistance. In the present study, experiments addressing the impact behavior of glass-fiber-reinforced DCPD were conducted to quantitatively evaluate its impact properties. The glass-fiber-reinforced polydicyclopentadiene composite utilized in impact tests was manufactured using structural reaction injection molding (S-RIM) because of its fast curing characteristics and low viscosity. The impact properties of the glass-fiber-reinforced DCPD (GF/DCPD) were quantitatively evaluated by varying its fiber content and decelerator solution. The impact properties of neat DCPD and GF/DCPD composites were examined with different amounts of decelerator solution under various temperatures from room temperature to cryogenic temperature to observe the ductile-to-brittle transition temperature (DBTT). With an increase in the fiber weight fraction of the GF/DCPD composite, the effect of the DBTT significantly decreased. However, the decreasing rate retarded as the weight fraction of the GF increased. The decreased DBTT with the addition of GF in the GF/DCPD can be attributed to the differences in the thermal expansion ratio and the interfacial force between neat DCPD and the fiber. A fractograph analysis demonstrates that the effect of the brittle (smooth) surface resulted in a lower impact absorbed energy when the temperature decreased, along with the increased amount of the decelerator.

Proppant Transport in Hydraulic Fractures by Creating a Capillary Suspension

2021 ◽  
Author(s):  
Ayomikun Bello
Keyword(s):  
Hydraulic Fracturing ◽  
Significant Risk ◽  
High Viscosity ◽  
Hydraulic Fractures ◽  
Main Task ◽  
Low Viscosity ◽  
Fracturing Fluids ◽  
Geological Conditions ◽  
Fracture Development ◽  
The Impact

Abstract Slick water fracturing fluids with high viscosity and minimal friction pressure losses are commonly employed in hydraulic fracturing nowadays. At the same time, high injection rates can be used to perform hydraulic fracturing to get the calculated fracture sizes. The conventional algorithm for conducting a standard proppant hydraulic fracturing includes performing a pressure test using a linear gel without a trial proppant pack to determine the quality of communication with the formation and the initial parameters of the fracture; and performing a mini-hydraulic fracturing on a cross-linked gel with a trial proppant pack (1000 - 2000 kg) to assess the parameters of the fracture development used to correct the design of the main hydraulic fracturing operation. However, in complex geological conditions associated with the presence of small clay barriers between the target formation and above or below the water-saturated layers, as well as in low-productive formations, this conventional method of conducting hydraulic fracturing operations using high-viscosity fluids is not always suitable. Hydraulic fracturing in thin-layer formations is associated with a significant risk of the tightness established by the fracture being broken, as well as fluids contained in the underlying or overlying layers being involved in the drainage process. Hydraulic fracturing in low-productive formations creates fractures that are similar in shape to radial fractures, reducing the efficiency and profitability of the impact due to inefficient use of materials and reagents. The main task in this situation is to limit the height of the fracture development and increase their length. It is necessary to use low-viscosity fracturing fluids with a high ability to transfer proppants to reduce the specific pressure in the fracture and control the height of the rupture. The goal of this research is to develop such fluid.

Deformation, heating and melting of solids in high-speed friction

1961 ◽  
Vol 260 (1303) ◽  
pp. 433-458 ◽  
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Frictional Heating ◽  
Vertical Axis ◽  
High Viscosity ◽  
Molten Material ◽  
General Behaviour ◽  
Low Viscosity ◽  
Heavy Loads ◽  
The Impact

An experimental study has been made of the effects of frictional heating on the deformation of solids rubbing at very high speeds and at reasonably heavy loads. A new method for measuring the friction under these conditions is described. A steel ball, rapidly spinning round its vertical axis, is allowed to fall a short distance and to bounce off an inclined flat solid surface. The friction of steel on various solids in a vacuum of ca . 10 -4 mm Hg, at sliding speeds up to 700 m/s, is determined from the measured direction of the ball’s horizontal velocity after the impact. In addition, separate piezo-electric measurements are made of the load and the friction force. Again the coefficient of friction is found to decrease with increasing sliding speed. The general behaviour is similar to that observed at light loads but there are important differences. With heavy loads the deformation of the solids appears to be primarily plastic. Within a very short time after being brought into contact with a fast-moving surface, solids with a sufficiently low melting point melt on a large scale so that a continuous film of molten material is developed over the area of contact. The resistance to motion is determined primarily by this liquid film so that it may now increase as the speed rises. The heating due to the shearing of this film causes the solid to melt away rapidly, and as a result the wear rate of such solids usually becomes great at high sliding speeds. Certain polymers, however, exhibit a greater wear resistance than metals and other solids which possess a low viscosity in the molten state. Calculations indicate that in these polymers, owing to their high viscosity, the temperature of the sheared film may be considerably higher than the melting temperature. As a consequence, a larger proportion of the heat developed by the shearing may be absorbed in the already molten material, and less heat will be available for further melting. Gas liberated by thermal decomposition may also reduce the friction and wear.

Characterization of Optical and Structure Properties of Polydimethylsiloxanes

2015 ◽  
Vol 827 ◽  
pp. 99-104 ◽  
Author(s):  
Hanif Sulistiya Nusa ◽  
Widi Astuti ◽  
Arief Sjamsulaksan Kartasasmita ◽  
Rova Virgana ◽  
Norman Syakir ◽  
...  
Keyword(s):  
Silicone Oil ◽  
Vitreoretinal Surgery ◽  
High Viscosity ◽  
Light Spectrum ◽  
Low Viscosity ◽  
Vis Spectroscopy ◽  
Before And After ◽  
Ft Ir ◽  
Structure Properties

Polydimethylsiloxanes (PDMS), (CH3)3SiO-[Si(CH3)2O]n-Si(CH3)3, known as silicone oil is a tamponade liquid which is very important in vitreoretinal surgery, especially in the treatment of complicated retinal detachment. Here, we investigated the optical properties and structure of silicone oil with high viscosity silicone oil of 5500 cSt and low viscosity silicone oil of 1300 cSt in order to understand the changing of physical properties of silicone oil before and after using in vitreoretinal surgery as a tamponade liquid and analyze the relationship between the tamponade duration and changed in silicone oil properties. From UV-Vis spectroscopy and refractometer measurement, it is found some changes in transmittance and refractive index values in both silicone oil after using as a tamponade liquid. From fourier transform infrared (FT-IR) spectroscopy, some additional of functional groups of N-H and O-H bond are observed at 1634.5 cm-1 and 3435.7 – 3764.5 cm-1, respectively. The changes of optical and structure properties of silicone oil after using as a tamponade liquid are assumed to be responsible in emulsification of silicone oil and affect the transmittance quality at visible light spectrum. However, in this study, there is no linear corelation between tamponade duration and changed in silicone oil properties.

The Analysis of Crude Oil Nature’s Impact on Oil Pipeline Underground Divulging Pollutant Migration

2014 ◽  
Vol 675-677 ◽  
pp. 332-335
Author(s):  
Guo Zhong Wu ◽  
Yu Wang ◽  
Han Bing Qi ◽  
Ying Ming Zhou ◽  
Dong Li
Keyword(s):  
Mass Transfer ◽  
Porous Medium ◽  
Multiphase Flow ◽  
Surface Temperature ◽  
Phase Distribution ◽  
Mass Transfer Process ◽  
High Viscosity ◽  
Oil Pipeline ◽  
Low Viscosity ◽  
The Impact

The oil pipeline burying divulging pollutant was taken as the object of study in this paper, the heat transfer and mass transfer process of which in the soil porous medium were carried by the numerical analysis. The oil phase change for multiphase flow leakage process for buried pipelines for oil, gas and water in the low temperature was considered, and the impact on multiphase leakage process of high and low viscosity of the oil phase viscosity properties was analyzed. It cited multiphase pipeline leak by using Fluent at different times during the course of the earth temperature field , the oil / water phase distribution , surface temperature, and the results showed that : there existed a big difference between the multiphase flow leakage process surface temperature changes and porous medium heat and mass transfer processes with the conditions of high viscosity and low viscosity conditions . Therefore, the impact of the physical properties on buried oil pipeline leak process at low temperatures is great.

scholarly journals On the orbital evolution of binaries with circumbinary discs

2020 ◽  
Vol 641 ◽  
pp. A64 ◽  
Author(s):  
R. M. Heath ◽  
C. J. Nixon
Keyword(s):  
Angular Momentum ◽  
Compact Object ◽  
High Viscosity ◽  
Orbital Evolution ◽  
Low Viscosity ◽  
Binary Evolution ◽  
Hydrodynamical Simulations ◽  
Binary Orbit ◽  
The Impact ◽  
Over Time

Circumbinary discs are generally thought to take up angular momentum and energy from the binary orbit over time through gravitational torques that are mediated by orbital resonances. This process leads to the shrinkage of the binary orbit over time, and it is important in a variety of astrophysical contexts including the orbital evolution of stellar binaries, the migration of planets in protoplanetary discs, and the evolution of black hole binaries (stellar and supermassive). The merger of compact object binaries provides a source of gravitational waves in the Universe. Recently, several groups have reported numerical simulations of circumbinary discs that yield the opposite result, finding that the binary expands with time. Here we argue that this result is primarily due to the choice of simulation parameters, made for numerical reasons, which differ from realistic disc parameters in many cases. We provide physical arguments, and then demonstrate with 3D hydrodynamical simulations, that thick (high pressure, high viscosity) discs drive sufficient accretion of high angular momentum material to force binary expansion, while in the more realistic case of thin (low pressure, low viscosity) discs there is less accretion and the binary shrinks. In the latter case, tides, which generally transfer angular momentum and energy from the more rapidly rotating object (the binary) to the less rapidly rotating object (the disc), are the dominant driver of disc-binary evolution. This causes the binary to shrink. We therefore conclude that for common circumbinary disc parameters, binaries with non-extreme mass ratios are expected to shrink over time. Expansion of the binary can occur if the disc viscosity is unusually high, which may occur in the very thick discs encountered in, for example, circumplanetary discs, super-Eddington AGN, or the outer regions of passive protostellar discs that are heated by the central protostar. We also provide discussion of the impact that some simplifications to the problem, that are prevalent in the literature and usually made for numerical convenience, have on the disc-binary evolution.

Effect of Vinyl-Terminated Silicone Oil Chain Length and Reinforcing Agent on the Properties of Silicone Rubber

2022 ◽  
Vol 905 ◽  
pp. 221-230
Author(s):  
Hong Wei Pan ◽  
Chong Guang Zang ◽  
Yu Long Zhang
Keyword(s):  
Silicone Rubber ◽  
Silicone Oil ◽  
High Strength ◽  
Compression Modulus ◽  
High Viscosity ◽  
Elongation At Break ◽  
Low Viscosity ◽  
Reinforcing Agent ◽  
Liquid Silicone Rubber ◽  
Liquid Silicone

To solve the problems of low strength and high viscosity of room temperature vulcanized liquid silicone rubber, a series of terminated vinyl silicone oil were designed and synthesized, and low viscosity and high strength silicone rubber were prepared by the mechanical reinforcing agent. the results show that the molecular structure of the vinyl-terminated silicone oil has a significant effect on the mechanical properties and viscosity of the silicone rubber, and the best performance is found when the content of vinyl-terminated silicone oil is 0.16%. The low viscosity and high strength silicone rubber prepared from it was reinforced by vinyl MQ resin and fumed silica, which had a significant effect on improving the performance. Its tensile strength increased to 5.03 MPa, elongation at break to 338.90%, and tear strength to 7.15 kN/m compared to conventional silicone rubber, while the hardness increased to 43°. The viscosity is 34.9 Pa•s. The compression modulus is 7.48 MPa.

scholarly journals The rheological behavior of fracture-filling cherts: example of Barite Valley dikes, Barberton Greenstone Belt, South Africa

2014 ◽  
Vol 6 (1) ◽  
pp. 1227-1264 ◽  
Author(s):  
M. Ledevin ◽  
N. Arndt ◽  
A. Simionovici
Keyword(s):  
South Africa ◽  
Rheological Behavior ◽  
Greenstone Belt ◽  
Colloidal Particles ◽  
Country Rock ◽  
Fluid Velocity ◽  
High Viscosity ◽  
Barberton Greenstone Belt ◽  
Low Viscosity ◽  
The Impact

Abstract. A 100 m-thick complex of near-vertical carbonaceous chert dikes marks the transition from the Mendon to Mapepe Formations (3260 Ma) in the Barberton Greenstone Belt, South Africa. Fracturing was intense in this area, as shown by the profusion and width of the dikes (ca. 1 m on average) and by the abundance of completely shattered rocks. The dike-and-sill organization of the fracture network and the upward narrowing of some of the large veins indicate that at least part of the fluid originated at depth and migrated upward in this hydrothermal plumbing system. Abundant angular fragments of silicified country rock are suspended and uniformly distributed within the larger dikes. Jigsaw-fit structures and confined bursting textures indicate that hydraulic fracturing was at the origin of the veins. The confinement of the dike system beneath an impact spherule bed suggests that the hydrothermal circulations were triggered by the impact and located at the external margin of a large crater. From the geometry of the dikes and the petrography of the cherts, we infer that the fluid that invaded the fractures was thixotropic. On one hand, the injection of black chert into extremely fine fractures is evidence for low viscosity at the time of injection; on the other hand, the lack of closure of larger veins and the suspension of large fragments in a chert matrix provide evidence of high viscosity soon thereafter. The inference is that the viscosity of the injected fluid increased from low to high as the fluid velocity decreased. Such rheological behavior is characteristic of media composed of solid and colloidal particles suspended in a liquid. The presence of abundant clay-sized, rounded particles of silica, carbonaceous matter and clay minerals, the high proportion of siliceous matrix and the capacity of colloidal silica to form cohesive 3-D networks through gelation, account for the viscosity increase and thixotropic behavior of the fluid that filled the veins. Stirring and shearing of the siliceous mush as it was injected imparted a low viscosity by decreasing internal particle interactions; then, as the flow rate declined, the fluid became highly viscous as the inter-particulate bonds (siloxane bonds, Si-O-Si) were reconstituted. The gelation of the chert was rapid and the structure persisted at low temperature (T < 200 °C) before fractures were sealed and chert indurated.

scholarly journals Effect of extreme cold temperatures on quasi-static indentation and impact behavior of woven carbon fiber epoxy composite sandwich panels with nomex honeycomb core

2021 ◽  
pp. 109963622199387
Author(s):  
Mathilde Jean-St-Laurent ◽  
Marie-Laure Dano ◽  
Marie-Josée Potvin
Keyword(s):  
Epoxy Composite ◽  
Impact Behavior ◽  
Effect Of Temperature ◽  
Cold Temperatures ◽  
Composite Sandwich Panels ◽  
Composite Sandwich ◽  
Static Indentation ◽  
Nomex Honeycomb ◽  
Extreme Cold ◽  
The Impact

The effect of extreme cold temperatures on the quasi-static indentation and the low velocity impact behavior of woven carbon/epoxy composite sandwich panels with Nomex honeycomb core was investigated. Impact tests were performed at room temperature, –70°C, and –150°C. Two sizes of hemispherical impactor were used combined to three different impactor masses. All the impact tests were performed at the same initial impact velocity. The effect of temperature on the impact behavior is investigated by studying the load history, load-displacement curves and transmitted energy as a function of time curves. Impact damage induced at various temperatures was studied using different non-destructive and destructive techniques. Globally, more damages are induced with impact temperature decreasing. The results also show that the effect of temperature on the impact behavior is function of the impactor size.

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