Journal articles: 'Bubble liquid mixture'

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Gao, Xin-Yi. "Density-fluctuation symbolic computation on the (3+1)-dimensional variable-coefficient Kudryashov–Sinelshchikov equation for a bubbly liquid with experimental support." Modern Physics Letters B 30, no. 15 (June 9, 2016): 1650217. http://dx.doi.org/10.1142/s0217984916502171.

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Liquids with gas bubbles are commonly seen in medical science, natural science, daily life and engineering. Nonlinear-wave symbolic computation on the (3[Formula: see text]+[Formula: see text]1)-dimensional variable-coefficient Kudryashov–Sinelshchikov model for a bubbly liquid is hereby performed. An auto-Bäcklund transformation and some solitonic solutions are obtained. With respect to the density fluctuation of the bubble-liquid mixture, both the auto-Bäcklund transformation and solitonic solutions depend on the bubble-liquid-viscosity, transverse-perturbation, bubble-liquid-nonlinearity and bubble-liquid-dispersion coefficient functions. We note that some shock waves given by our solutions have been observed by the gas-bubble/liquid-mixture experiments. Effects on a bubbly liquid with respect to the bubble-liquid-viscosity, transverse-perturbation, bubble-liquid-nonlinearity and bubble-liquid-dispersion coefficient functions might be detected by the future gas-bubble/liquid-mixture experiments.

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ABE, H., M. MORIKAWA, T. UEDA, R. NOMURA, Y. OKUDA, and S. N. BURMISTROV. "Visual observation of the bubble dynamics in normal 4He, superfluid 4He and superfluid 3He–4He mixtures." Journal of Fluid Mechanics 619 (January 25, 2009): 261–75. http://dx.doi.org/10.1017/s0022112008004436.

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In order to compare the bubble dynamics of various quantum liquids, we performed the visual observation of a sound-induced bubble in a normal liquid 4He, pure superfluid 4He, and superfluid 3He–4He liquid mixtures of saturated and unsaturated 3He concentrations. When an acoustic wave pulse was applied to these liquids under saturated vapour pressure, a macroscopic bubble was generated on the surface of a piezoelectric transducer. For all liquids, the size of the bubble increased, as a higher voltage was applied to the transducer at a fixed temperature. In the normal 4He we observed a primary bubble surrounded with many small bubbles which ascended upward together. In contrast to normal phase, only one bubble was generated in the superfluid 4He, and its shape proved to be highly irregular with an ill-defined surface. In the 3He saturated superfluid mixture, we also observed a solitary bubble but with a nearly perfect spherical shape. The bubble in this mixture expanded on the transducer surface, grew to a maximum size of the order of 1 mm and then started shrinking. As the bubble detached from the transducer with shrinking, we clearly detected an origination of the upward jet flow which penetrated the bubble. The jet velocity in the liquid mixture was approximately 102–103 times smaller than in water. At the final stage of the process we could sometimes observe a vortex ring generation. It is interesting that, though the bubble size and time scale of the phenomenon differ from those in water, the behaviour in the collapsing process had much in common with the simulation study of the vortex ring generation in water. In addition, for the mixture with the unsaturated 3He concentration of about 25% at 600 mK, the shape of the upward jet was observed distinctly, using more precise measurement with shadowgraph method.

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Vorobyev, M. A., O. N. Kashinskiy, P. D. Lobanov, and A. V. Chinak. "Bubble flow formation regimes in viscous liquid." Proceedings of the Mavlyutov Institute of Mechanics 11, no. 2 (2016): 254–62. http://dx.doi.org/10.21662/uim2016.2.037.

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The experimental study of the process of bubble detachment from a single capillary in downward liquid flow was performed. The glycerin was used as a working liquid. In order to study the effect of physical properties of liquid on the formation of bubbles experiment was conducted at different temperatures. Presented average bubble size is depended on parameters such as gas flow rate, temperature and volume velocity of liquid, as well as the capillary diameter. The data about the most characteristic mode of formation of the gas-liquid mixture was obtained. It is shown that coalescence of bubbles near the capillary is the process that determines the type of bubbles size distribution in the fluid flow. The regimes of bubble formation most suitable for the generation of a monodisperse, and bidisperse gas-liquid mixture are presented in the study.

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Oladokun, Olagoke, Arshad Ahmad, Adnan Ripin, Tuan A. T. Abdullah, Bemgba B. Nyakuma, Nur Amira Hadi, Ali H. Al-Shatri, Murtala Ahmed, Habib Alkali, and Aliyu A. Bello. "Modelling ultrasound waves bubble formation in ethanol/ethyl acetate azeotrope mixture." E3S Web of Conferences 90 (2019): 02005. http://dx.doi.org/10.1051/e3sconf/20199002005.

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The separation of an azeotropic mixture such as ethanol/ethyl acetate in distillation process can be enhanced by ultrasound wave. The application of ultrasound wave creates bubble cavitation in the mixture and shifts the vapour-liquid equilibrium favouring the separation of the azeotropic mixture. This study investigates the formation of bubbles in the mixture through modelling and simulation. The results obtained show that bubble formation at low ultrasound frequency is favoured by the increase in intensity, which has a direct relation to sonic pressure. The optimal sonic pressure for bubble formation at equilibrium is 5 atm and conforms to the model for small bubble formation with radius of 0.14 /<m. Furthermore, the maximum possible number of bubbles at equilibrium in the ethanol/ethyl acetate azeotropic mixture of 1 L is 91 × 1015. The developed model can be used to determine the optimal sonic pressure, sound intensity, size of bubble, and possible number of bubbles formed at equilibrium.

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D'AGOSTINO, LUCA, FABRIZIO D'AURIA, and CHRISTOPHER E. BRENNEN. "On the inviscid stability of parallel bubbly flows." Journal of Fluid Mechanics 339 (May 25, 1997): 261–74. http://dx.doi.org/10.1017/s0022112097005211.

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This paper investigates the effects of bubble dynamics on the stability of parallel bubbly flows of low void fraction. The equations of motion for the bubbly mixture are linearized for small perturbations and the parallel flow assumption is used to obtain a modified Rayleigh equation governing the inviscid stability problem. This is then used for the stability analysis of two-dimensional shear layers, jets and wakes. Inertial effects associated with the bubble response and energy dissipation due to the viscosity of the liquid, the heat transfer between the two phases, and the liquid compressibility are included. Numerical solutions of the eigenvalue problems for the modified Rayleigh equation are obtained by means of a multiple shooting method. Depending on the characteristic velocities of the various flows, the void fraction, and the ambient pressure, the presence of air bubbles can induce significant departures from the classical stability results for a single-phase fluid.

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SMEULDERS, D. M. J., and M. E. H. VAN DONGEN. "Wave propagation in porous media containing a dilute gas–liquid mixture: theory and experiments." Journal of Fluid Mechanics 343 (July 25, 1997): 351–73. http://dx.doi.org/10.1017/s0022112097005983.

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The influence of a small amount of gas within the saturating liquid of a porous medium on acoustic wave propagation is investigated. It is assumed that the gas volumes are spherical, homogeneously distributed, and that they are within a very narrow range of bubble sizes. It is shown that the compressibility of the saturating fluid is determined by viscous, thermal, and a newly introduced Biot-type damping of the oscillating gas bubbles, with mean gas bubble size and concentration as important parameters. Using a super-saturation technique, a homogeneous gas–liquid mixture within a porous test column is obtained. Gas bubble size and concentration are measured by means of compressibility experiments. Wave reflection and propagation experiments carried out in a vertical shock tube show pore pressure oscillations, which can be explained by incorporating a dynamic gas bubble behaviour in the linear Biot theory for plane wave propagation.

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Kern, Ju¨rgen, and Peter Stephan. "Investigation of Decisive Mixture Effects in Nucleate Boiling of Binary Mixtures Using a Theoretical Model." Journal of Heat Transfer 125, no. 6 (November 19, 2003): 1116–22. http://dx.doi.org/10.1115/1.1622716.

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In the present paper an attempt is made to clarify the influence of mixture effects upon heat transfer in nucleate boiling of binary mixtures. The studies are based on a theoretical model that is briefly summarized. Evaluating heat and mass transfer around a single vapor bubble emphasizes a strong influence of the so-called micro region where the liquid-vapor phase interface approaches the wall. Due to the preferential evaporation of one component of the mixture, strong concentration gradients occur in the micro region. These microscale composition effects cause diffusive mass transfer, Marangoni convection, and a variation of the liquid-vapor phase equilibrium as well as a variation of the thermophysical properties. From a macroscopic point of view the bubble site density and the departure diameter vary with the composition of the liquid. By means of parameter studies decisive mixture effects are identified and their relevance in the nucleate boiling process is stated. The heat transfer coefficient crucially depends on the bubble site density and departure diameter. For increasing bubble site density, the influence of microscopic concentration gradients increases. But only the variation of liquid-vapor phase equilibrium becomes important, while diffusive mass transfer and Marangoni convection can be neglected.

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Minemura, Kiyoshi, and Tomomi Uchiyama. "Three-Dimensional Calculation of Air-Water Two-Phase Flow in Centrifugal Pump Impeller Based on a Bubbly Flow Model." Journal of Fluids Engineering 115, no. 4 (December 1, 1993): 766–71. http://dx.doi.org/10.1115/1.2910210.

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To predict the behavior of gas-liquid two-phase flows in a centrifugal pump impeller, a three-dimensional numerical method is proposed on the basis of a bubbly flow model. Under the assumption of homogeneous bubbly flow entraining fine bubbles, the equation of motion of the mixture is represented by that of liquid-phase and the liquid velocity is expressed as a potential for a quasi-harmonic equation. This equation is solved with a finite element method to obtain the velocities, and the equation of motion of an air bubble is integrated numerically in the flow field to obtain the void fraction. These calculations are iterated to obtain a converged solution. The method has been applied to a radial-flow pump, and the results obtained have been confirmed by experiments within the range of bubbly flow regime.

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Wang, Yi-Chun, and C. E. Brennen. "One-Dimensional Bubbly Cavitating Flows Through a Converging-Diverging Nozzle." Journal of Fluids Engineering 120, no. 1 (March 1, 1998): 166–70. http://dx.doi.org/10.1115/1.2819642.

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A nonbarotropic continuum bubbly mixture model is used to study the one-dimensional cavitating flow through a converging-diverging nozzle. The nonlinear dynamics of the cavitation bubbles are modeled by the Rayleigh-Plesset equation. Analytical results show that the bubble/bubble interaction through the hydrodynamics of the surrounding liquid has important effects on this confined flow field. One clear interaction effect is the Bernoulli effect caused by the growing and collapsing bubbles in the nozzle. It is found that the characteristics of the flow change dramatically even when the upstream void fraction is very small. Two different flow regimes are found from the steady state solutions and are termed: quasi-steady and quasi-unsteady. The former is characterized by large spatial fluctuations downstream of the throat which are induced by the pulsations of the cavitation bubbles. The quasi-unsteady solutions correspond to flashing flow. Bifurcation occurs as the flow transitions from one regime to the other. An analytical expression for the critical bubble size at the bifurcation is obtained. Physical reasons for this quasi-static instability are also discussed.

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10

SMEREKA, PETER. "A Vlasov equation for pressure wave propagation in bubbly fluids." Journal of Fluid Mechanics 454 (March 10, 2002): 287–325. http://dx.doi.org/10.1017/s002211200100708x.

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The derivation of effective equations for pressure wave propagation in a bubbly fluid at very low void fractions is examined. A Vlasov-type equation is derived for the probability distribution of the bubbles in phase space instead of computing effective equations in terms of averaged quantities. This provides a more general description of the bubble mixture and contains previously derived effective equations as a special case. This Vlasov equation allows for the possibility that locally bubbles may oscillate with different phases or amplitudes or may have different sizes. The linearization of this equation recovers the dispersion relation derived by Carstensen & Foldy. The initial value problem is examined for both ideal bubbly flows and situations where the bubble dynamics have damping mechanisms. In the ideal case, it is found that the pressure waves will damp to zero whereas the bubbles continue to oscillate but with the oscillations becoming incoherent. This damping mechanism is similar to Landau damping in plasmas. Nonlinear effects are considered by using the Hamiltonian structure. It is proven that there is a damping mechanism due to the nonlinearity of single-bubble motion. The Vlasov equation is modified to include effects of liquid viscosity and heat transfer. It is shown that the pressure waves have two damping mechanisms, one from the effects of size distribution and the other from single-bubble damping effects. Consequently, the pressure waves can damp faster than bubble oscillations.

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Himm, J. F., and L. D. Homer. "A model of extravascular bubble evolution: effect of changes in breathing gas composition." Journal of Applied Physiology 87, no. 4 (October 1, 1999): 1521–31. http://dx.doi.org/10.1152/jappl.1999.87.4.1521.

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Observations of bubble evolution in rats after decompression from air dives (O. Hyldegaard and J. Madsen. Undersea Biomed. Res. 16: 185–193, 1989; O. Hyldegaard and J. Madsen. Undersea Hyperbaric Med. 21: 413–424, 1994; O. Hyldegaard, M. Moller, and J. Madsen. Undersea Biomed. Res. 18: 361–371, 1991) suggest that bubbles may resolve more safely when the breathing gas is a heliox mixture than when it is pure O2. This is due to a transient period of bubble growth seen during switches to O2 breathing. In an attempt to understand these experimental results, we have developed a multigas-multipressure mathematical model of bubble evolution, which consists of a bubble in a well-stirred liquid. The liquid exchanges gas with the bubble via diffusion, and the exchange between liquid and blood is described by a single-exponential time constant for each inert gas. The model indicates that bubbles resolve most rapidly in spinal tissue, in adipose tissue, and in aqueous tissues when the breathing gas is switched to O2 after surfacing. In addition, the model suggests that switching to heliox breathing may prolong the existence of the bubble relative to breathing air for bubbles in spinal and adipose tissues. Some possible explanations for the discrepancy between model and experiment are discussed.

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Paramanantham, SalaiSargunan S., Dong-Hyun Kim, and Warn-Gyu Park. "Numerical Study of Bubble Behavior under Gradient Flows during Subcooled Flow Boiling in Vertical Flow Channel." Symmetry 12, no. 4 (April 12, 2020): 611. http://dx.doi.org/10.3390/sym12040611.

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In this study, we examined the condensing behavior of single and multiple bubbles of pure steam in a subcooled liquid phase using a fully compressible two-phase homogeneous mixture method that is solved by an implicit dual-time preconditioned technique. The interface between the liquid and vapor phases was determined by the advection equations using a compressive high-resolution interfacing capturing method. The spurious current reduced near the interface, a smoothing filter is applied to the progress curvature calculation. The sensitivity study carried out to predict the empirical constant by using Lee’s mass transfer model. A comparison of the numerical and experimental results highlighted that the proposed model accurately predicted the behavior of the definite condensing bubble. Furthermore, the single and multiple bubble condensation behaviors were investigated for different initial subcooled temperatures, and bubble diameters under various gradient flow, such as velocity gradient, temperature gradient, and velocity and temperature gradients. Subsequently, the effect of multiple bubbles flows in different bubble pattern forms, and their condensation was studied. The coalescence of bubbles depends on the subcooled temperature. Furthermore, the bubble diameter, the gap between the bubbles, and the flow rate of the bubbles were also observed.

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Mohammadein, S. A., and A. F. Abu-Bakr. "The growth of vapour bubble in a superheated liquid between two phase turbulent flow." Canadian Journal of Physics 88, no. 5 (May 2010): 317–24. http://dx.doi.org/10.1139/p10-022.

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In this paper, the growth of a vapour bubble in superheated water for two-phase turbulent flow is studied. The growth problem is formulated by mass and momentum equations under physical assumptions between two finite boundaries. The analytical solution is obtained in terms of the vapour bubble radius. The bubbly growth is affected by thermal diffusivity, superheating, and the Péclet number. The fact that the scale of the bubble is larger than the scale of the turbulence in the mixture surrounding the growing bubble is considered. The previous models of growth for laminar flow are obtained as a special cases of the present model for some values of the parameters a, b, n, and φ0, respectively.

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Zeng, Lei, Daniel Velez, Jiacai Lu, and Gretar Tryggvason. "Numerical Studies of Disperse Three-Phase Fluid Flows." Fluids 6, no. 9 (September 6, 2021): 317. http://dx.doi.org/10.3390/fluids6090317.

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The dynamics of a three-phase gas–liquid–liquid multiphase system is examined by direct numerical simulations. The system consists of a continuous liquid phase, buoyant gas bubbles, and smaller heavy drops that fall relative to the continuous liquid. The computational domain is fully periodic, and a force equal to the weight of the mixture is added to keep it in place. The governing parameters are selected so that the terminal Reynolds numbers of the bubbles and the drops are moderate; while the effect of bubble deformability is examined by changing its surface tension, the surface tension for the drops is sufficiently high so they do not deform. One bubble in a “unit cell” and eight freely interacting bubbles are examined. The dependency of the slip velocities, the velocity fluctuations, and the distribution of the dispersed phases on the volume fraction of each phase are examined. It is found that while the distribution of drops around a single bubble in a “unit cell” is uneven and depends on its deformability, the distribution of drops around freely interacting bubbles is relatively uniform for the parameters examined in this study.

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LOUISNARD, OLIVIER, FRANCISCO J. GOMEZ, and ROMAIN GROSSIER. "Segregation of a liquid mixture by a radially oscillating bubble." Journal of Fluid Mechanics 577 (April 19, 2007): 385–415. http://dx.doi.org/10.1017/s002211200700479x.

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A theoretical formulation is proposed for forced mass transport by pressure gradients in a liquid binary mixture around a spherical bubble undergoing volume oscillations in a sound field. Assuming the impermeability of the bubble wall to both species, diffusion driven by pressure gradients and classical Fick-diffusion must cancel at the bubble wall, so that an oscillatory concentration gradient arises in the vicinity of the bubble. The Péclet number pe is generally high in typical situations and Fick diffusion cannot restore equilibrium immediately, so that an asymptotic average concentration profile may progressively build up in the liquid over large times. Such a behaviour is reminiscent of the so-called rectified diffusion problem, leading to slow growth of a gas bubble oscillating in a sound field. A rigorous method formerly proposed by Fyrillas & Szeri (J. Fluid Mech. vol. 277, 1994, p. 381) to solve the latter problem is used to solve the present one. It is based on splitting the problem into a smooth part and an oscillatory part. The smooth part is solved by a multiple scales method and yields the slowly varying average concentration field everywhere in the liquid. The oscillatory part is obtained by matched asymptotic expansions in terms of the small parameter pe−1/2: the inner solution is required to satisfy the oscillatory balance between pressure diffusion and Fick diffusion at the bubble wall, while the outer solution is required to be zero. Matching both solutions yields a unique splitting of the problem. The final analytical solution, truncated to leading order, compares successfully to direct numerical simulation of the full convection–diffusion equation. The analytical expressions for both smooth and oscillatory parts are calculated for various sets of bubble parameters: driving pressure, frequency and ambient radius. The smooth problem always yields an average depletion of the heaviest species at the bubble wall, only noticeable for large molecules or nano-particles. For driving pressures sufficiently high to yield inertial oscillations of the bubble, the oscillatory problem predicts a periodic peak excess concentration of the heaviest species at the bubble wall at each collapse, lingering on several tens of the time of the characteristic duration of the bubble rebound. The two effects may compete for large molecules and practical implications of this segregation phenomenon are proposed for various processes involving acoustic cavitation.

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Ye, Yanghui, Cong Dong, Zhiguo Zhang, and Yangyang Liang. "Considering the Diffusive Effects of Cavitation in a Homogeneous Mixture Model." Processes 8, no. 6 (June 3, 2020): 662. http://dx.doi.org/10.3390/pr8060662.

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Homogeneous mixture models are widely used to predict the hydrodynamic cavitation. In this study, the constant-transfer coefficient model is implemented into a homogeneous cavitation model to predict the heat and mass diffusion. Modifications are made to the average bubble temperature and the Peclet number for thermal diffusivity in the constant-transfer coefficient model. The evolutions of a spherical bubble triggered by negative pressure pulse are simulated to evaluate the prediction of heat and mass diffusion by the homogeneous model. The evolutions of three bubbles inside a rectangular tube are simulated, which show good accuracy of the homogeneous model for multibubbles in stationary liquid.

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Ismayilov, Gafar G., Vugar M. Fataliyev, and Elman Kh Iskenderov. "Investigating the impact of dissolved natural gas on the flow characteristics of multicomponent fluid in pipelines." Open Physics 17, no. 1 (May 9, 2019): 206–13. http://dx.doi.org/10.1515/phys-2019-0021.

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Abstract The conventional equations for describing the flow characteristics of the mixtures merely consider fluid that is homogenic, if it is above the bubble point conditions but ignore that a system containing sub-micron sized gas or vapor bubbles distributed throughout the volume of the liquid, which can exhibit unexpected heterogenic and complex phase properties. In this paper, a new mathematical model for the flowing gas-liquid mixture is presented, which has been proposed considering the colloidal feature of the system above the saturation or bubble point pressure. This approach is more in line with the actual dynamic performance of the oil and gas mixture export pipeline. Experimental data, simulations and field case studies validate the new proposed mathematical model of flow characteristics in pipeline. The obtained results confirmed that the calculated data are in good agreement with the experimental data. Based on Azerbaijan oil-gas-condensate field “Guneshli” data, this new model was used for calculating the condition in which the transformation of the flow characteristics from stable into instable is occurred. It has been discovered that the flow becomes unstable at a pressure about 30% higher than Bubble Point Pressure, which causes pulsation effect in the pipeline structure. However, homogenic behavior should be observed in this hydrodynamic condition. Also, the model provides a guideline on how to optimize the flow rate by adjusting the pipeline parameters to minimize the flow resistance, liquid slugging and hydraulic hammering effects, which cause instable operation.

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Shagapov, Vladislav Sh, Marat N. Galimzyanov, and Uliana O. Agisheva. "Single Waves in a Gas-Liquid Bubble Mixture." Izvestiya of Saratov University. New Series. Series: Mathematics. Mechanics. Informatics 20, no. 2 (2020): 232–40. http://dx.doi.org/10.18500/1816-9791-2020-20-2-232-240.

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Gavrilev, Stepan, Mikhail Ivanov, and Semen Totunov. "THE MONITORING OF THE LIQUID-GAS MIXTURE PARAMETERS BY THE PASSIVE ACOUSTIC METHOD." VOLUME 39, VOLUME 39 (2021): 148. http://dx.doi.org/10.36336/akustika202139148.

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The considers the actual problem of determining the dispersed composition of the gas phase in a liquid medium. The work uses a passive acoustic method based on the interaction between the vibration frequency of bubbles and their size. On the experimental setup, acoustic waves emitted by air bubbles in water were recorded using a hydrophone. The sizes of the bubbles were determined by the spectra of the recorded signal. In the course of the experiments, the bubble radius was varied from 1.7 to 2.4 mm. The spectrogram of the signal was used to estimate the intensity of the release of bubbles in the volume of the experimental apparatus. Using the technique of synchronous filming, a video recording of the process of bubbles allocation at the apparatus was made. The analysis of the recorded video showed the correspondence of the determination of the parameters of the liquid-gas mixture. There are proposed various application scenarios of the passive acoustic method in the oil and gas industry.

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Lepikhin, S. A., and M. N. Galimzyanov. "High pressures and temperatures in the bubble liquid when it flows through the nozzle." Proceedings of the Mavlyutov Institute of Mechanics 4 (2006): 83–89. http://dx.doi.org/10.21662/uim2006.1.008.

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The stationary flow of a bubble gas-liquid mixture in a nozzle of circular cross-section is considered. The possibility of realizing superhigh temperatures and pressures in the gas phase at the nozzle site near the minimum cross section is analyzed. The effect of the parameters (the initial radius and the volume content of bubbles that determine the composition of the volume flow of liquid fed into the nozzle) on the flow pattern is studied.

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Murai, Y., and Y. Matsumoto. "Numerical Study of the Three-Dimensional Structure of a Bubble Plume." Journal of Fluids Engineering 122, no. 4 (June 20, 2000): 754–60. http://dx.doi.org/10.1115/1.1313245.

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The whole behavior and the micro scale flow characteristics of a three-dimensional bubble plume are investigated numerically. The bubble plume drives liquid convection in a tank due to strong local two-phase interaction so that the Eulerian-Lagrangian model is formulated with emphasis on the translational motions of the bubble. In this model, each bubble motion is tracked in a bubbly mixture which is treated as a continuum. The three-dimensional numerical results reveal several particular structures, such as swaying and swirling structures of the bubble plume. These simulated flow structures show qualitatively good agreement with the experimental observations. Furthermore, the detailed behavior in the bubble plume is clarified by various analysis to discuss the dominant factors causing such the strong three-dimensionality. [S0098-2202(00)00904-4]

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Vledouts, A., J. Quinard, N. Vandenberghe, and E. Villermaux. "Explosive fragmentation of liquid shells." Journal of Fluid Mechanics 788 (January 5, 2016): 246–73. http://dx.doi.org/10.1017/jfm.2015.716.

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The forced radial expansion of a spherical liquid shell by an exothermic chemical reaction is a prototypical configuration for the explosion of cohesive materials in three dimensions. The shell is formed by the capillary pinch off of a thin liquid annular jet surrounding a jet of reactive gaseous mixture at ambient pressure. The encapsulated gas in the resulting liquid bubble is a mixture of hydrogen and oxygen in controlled relative proportions, which is ignited by a laser plasma aimed at the centre of the bubble. The strongly exothermic combustion of the mixture induces the expansion of the hot burnt gas, pushing the shell radially outwards in a violently accelerated motion. That motion triggers the instability of the shell, developing thickness modulations ultimately piercing it in a number of places. The capillary retraction of the holes concentrates the liquid constituting the shell into a web of ligaments, whose breakup leads to stable drops. We offer a comprehensive description of the overall process, from the kinematics of the shell initial expansion, to the final drop size distribution as a function of the composition of the gas mixture, the initial shell radius and thickness.

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Levitsky, Semyon, Rudolf Bergman, and Jehuda Haddad. "Sound propagation in viscoelastic pipe with liquid‐bubble mixture." Journal of the Acoustical Society of America 123, no. 5 (May 2008): 3703. http://dx.doi.org/10.1121/1.2935115.

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Cai, Chang, Hong Liu, Xi Xi, Ming Jia, and Hongchao Yin. "Bubble growth model in uniformly superheated binary liquid mixture." International Journal of Heat and Mass Transfer 127 (December 2018): 629–38. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2018.07.084.

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Baidakov, Vladimir G., Sergey P. Protsenko, and Vasiliy M. Bryukhanov. "Bubble nucleation in a Lennard-Jones binary liquid mixture." Chemical Physics Letters 663 (October 2016): 57–60. http://dx.doi.org/10.1016/j.cplett.2016.09.073.

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Volnenko, А., А. Leudanski, Y. Apimakh, B. Korganbayev, and D. Zhumadullayev. "POLYMER WASTES’ FLOTATION SEPARATION RESEARCH RESULTS." NEWS of National Academy of Sciences of the Republic of Kazakhstan 6, no. 444 (December 15, 2020): 50–58. http://dx.doi.org/10.32014/2020.2518-170x.130.

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For separation of plastic wastes (polyamide (PA), acrylonitrile butadiene styrene (ABS) and polystyrene (PS), a flotation method is proposed. Using this method, the effect of concentration of surface-active substances (surfactants), which were used as polidocanol, sulphanole and a mixture of surfactants containing sodium laureth sulfate and diethanolamide, was studied. The research results analysis of the flotation separation of a mixture of crushed plastic wastes was carried out according to the calculated values of the extraction of a floated component ε and the purity of a concentrate β. It was noted that the maximum extraction of the floated component depends on the polymer and surfactant type. A mixture of surfactants at lower concentrations allows to achieve greater extraction of the floated component with less foaming ability. The research results on the extraction of polystyrene from the air flow rate at various concentrations of surfactants’ mixture show that the extraction has a maximum at a certain air flow rate. At low air flow rates, the working volume of liquid is not saturated enough with gas bubbles. If the optimal value of air flow rates is exceeded, many gas bubbles are formed that are not involved in the flotation process. The research results on the extraction of polystyrene from the aerated liquid layer height at various concentrations of surfactants’ mixture show that, at a low height of the aerated liquid layer, the probability of collision of a plastic particle with an air bubble is low and some potentially floated particles seek the bottom of an apparatus without having time to collide with an air bubble. When assessing the influence of liquid temperature on the flotation process, it was found that increasing the liquid temperature above 20°C leads to a sharp decrease in ABS and PS extraction. This is explained by the fact that the dependence of the surfactants’ foaming ability on the temperature is characterized by solubility curves and for most surfactants they have an extremum.

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Levitsky, Semyon, Rudolf Bergman, and Jehuda Haddad. "Pressure Waves Propagation in an Elastic Shell with Polydisperse Liquid-Gas Mixture." Applied Mechanics and Materials 105-107 (September 2011): 259–62. http://dx.doi.org/10.4028/www.scientific.net/amm.105-107.259.

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The target of the paper is modeling of the influence of small amount of free gas on pressure wave propagation in a cylindrical elastic shell, filled with viscous liquid. Heterogeneity of the bubble population and the basic sources of wave attenuation (wall friction, heat exchange between gas in microbubbles and surrounding liquid, viscous and acoustic losses) are taken into account. The dispersion equation for the waveguide is studied numerically and effect of the bubble size distribution on the longitudinal wave propagation is discussed.

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Sehabiague, Laurent, and Badie I. Morsi. "Hydrodynamic and Mass Transfer Characteristics in a Large-Scale Slurry Bubble Column Reactor for Gas Mixtures in Actual Fischer–Tropsch Cuts." International Journal of Chemical Reactor Engineering 11, no. 1 (June 18, 2013): 83–102. http://dx.doi.org/10.1515/ijcre-2012-0042.

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Abstract The hydrodynamics (gas holdup, Sauter mean bubble diameter, d 32) and the overall volumetric liquid-side mass transfer coefficients (kLa) were measured in a large-scale (0.29 m ID, 3 m high) slurry bubble column reactor (SBCR) for He/N2 gaseous mixtures, as surrogates for syngas, in three different Fisher–Tropsch (F-T) products (liquid paraffins mixture, light F-T cut and heavy F-T cut) in the presence and absence of three different solids (spent iron oxides catalyst, alumina powder and Puralox alumina). The effects of pressure (10–30 bar), temperature (up to 500 K), superficial gas velocity (0.14–0.26 m/s), solid concentration (0–20 vol.%) and gas density on these design parameters were investigated. The experimental data revealed that increasing the reactor pressure or gas density increased the gas holdup and decreased d 32, by increasing the population of the small gas bubbles, which increased the overall kLa values for all the gas mixtures used in the three F-T cuts under most of the operating conditions employed. Increasing temperature increased the gas holdup in the three F-T cuts, except for N2-light F-T cut, where the gas holdup values remained almost constant from 400 to 500 K. Increasing the slurry concentration decreased the gas holdup and increased d 32, mainly for gaseous mixtures with high He mole fractions, which decreased the overall kLa under all conditions used. Increasing the gas superficial velocities (UG ) increased the gas holdup and kLa values, even though d 32 was found to increase or decrease with increasing UG . Increasing the He mole fraction in the He/N2 gaseous mixture at constant pressure led to low gas holdup and high d 32 which decreased kLa values, and under similar operating conditions, kLa values of He as a single gas were always lower than those of N2 as a single gas. Increasing the He mole fraction in the He/N2 gaseous mixture at constant density, however, was found to have negligible effect on the gas holdup, d 32 and subsequently on the overall kLa. The gas holdup, the overall kLa and the population of the small gas bubbles for N2 in the liquid paraffins mixture were greater than those in the light F-T cut. Operating the SBCR with the heavy F-T cut resulted in the lowest gas holdup and the largest gas bubbles size which led to the lowest gas–liquid interfacial area and consequently, the lowest kLa values. Also, under the operating conditions investigated, the behavior of overall kLa for the gases used in the three F-T cuts in the presence and absence of the three solids employed was controlled by that of the gas–liquid interfacial area (a). Using the data obtained, two novel empirical correlations for predicting the gas holdup and the overall kLa for gases specifically in F-T cuts are proposed.

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Duplat, Jérôme. "Dynamics of expansion and collapse of explosive two-dimensional bubbles." Journal of Fluid Mechanics 859 (November 22, 2018): 677–90. http://dx.doi.org/10.1017/jfm.2018.804.

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An explosive gas mixture of hydrogen and oxygen is introduced in liquid water between two horizontal walls, forming a flat cylindrical bubble. Ignition and explosion of the bubble lead to a large depressurized cavity that finally implodes. We investigate the dynamics of the bubble collapse, which is qualitatively similar to the collapse of a spherical bubble. It exhibits a slightly weaker singularity than for spherical bubbles. We also analyse the explosion process. Starting with an initial radius $R_{0}$, the bubble reaches a maximal radius $R_{max}$ that depends on the gap thickness $h$ between the two walls: for a thinner gap, the condensation of water vapour is more efficient, the overpressure consecutive to the combustion is weaker, and its duration is shorter. This leads to a smaller maximal radius $R_{max}$. An indirect measurement of the transport coefficient of hot water vapour can be inferred from this observation.

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Ribeiro, J. A., A. S. Reis, P. S. Avendaño, C. H. Ataíde, and Marcos A. S. Barrozo. "Experimental and CFD Simulation of a Bubble Column." Materials Science Forum 727-728 (August 2012): 1824–29. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1824.

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The numerical simulation in fluid mechanics has large application in chemical engineering. The objective of the present work is the analyze of a computational model for the fluid dynamics behaviour of a bubble column of the geometry cylindrical non regular with multiphase mixture. Experimental data and CFD results of the hydrodynamics of gaseous and liquid phases have been compared. Five different diameters of bubbles have been used in the CFD simulations. The comparisons between CFD simulations and experimental data show that the Eulerian-Eulerian approach provides a computational model that represents the process satisfactorily.

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Vdovenko, I. I., and N. N. Vdovenko. "Propagation of weak disturbances in warm water with air bubbles." Proceedings of the Mavlyutov Institute of Mechanics 12, no. 1 (2017): 135–42. http://dx.doi.org/10.21662/uim2017.1.019.

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The features of reflection and refraction of harmonic waves at the interface between a ”pure“ liquid and a liquid with bubbles with a vapor-gas mixture under direct and oblique incidence are studied. A numerical analysis is made of the effect of the initial volumetric gas content αg0 for two initial bubble sizes a0=10–6 m and 10–3 m. The influence of the disturbance frequencies on the reflection and refraction coefficients of sound in direct incidence and on the dependence of the angle of refraction on the angle of incidence is studied.

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MASUDA, Ryo, Kiyomi KAWAMURA, Makoto NAGAOKA, Masahiko MASUBUCHI, and Keisuke KOMORI. "Numerical Study of Liquid Fuel / Cavitation Bubble Mixture Injection Technique." TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B 78, no. 793 (2012): 1584–97. http://dx.doi.org/10.1299/kikaib.78.1584.

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Matsumoto, Y. "Contribution of Homogeneous Condensation Inside Cavitation Nuclei to Cavitation Inception." Journal of Fluids Engineering 108, no. 4 (December 1, 1986): 433–37. http://dx.doi.org/10.1115/1.3242600.

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The response of a small gas bubble, so-called cavitation nucleus, to the reduction of ambient pressure is investigated theoretically and experimentally. Numerical results show that the gas mixture inside the bubble expands adiabatically and the temperature of the mixture decreases rapidly at the first stage, however the temperature recovers soon to the surrounding liquid temperature by homogeneous condensation which forms a mist inside the bubble. Consequently, the bubble grows almost isothermally. Experiments have been performed using a hydro-shock tube. The radius of a small bubble has been measured by a light-scattering method whose time resolving power is one micro-second. The experimental results are found to be in good agreement with the numerical results calculated using the ambient pressure change measured in the test section.

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34

Temkin, S. "Attenuation and dispersion of sound in bubbly fluids via the Kramers—Kronig relations." Journal of Fluid Mechanics 211 (February 1990): 61–72. http://dx.doi.org/10.1017/s0022112090001495.

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Sound propagation in a dilute bubble–liquid mixture is studied by means of the Kramers–Kronig relationships, which relate the real and imaginary parts of the general susceptibility of a linear medium. These relationships are adopted for the case of acoustic waves, where they become coupled integral equations. A simple but approximate procedure is used to obtain from these equations the phase speed of sound waves for the case when the attenuation coefficient is independently known. The procedure can be used to obtain the speed of propagation of sound waves in acoustic media having internal dissipation, but is here applied only to fluids containing radially pulsating bubbles. Approximate results for the speed of propagation and for the attenuation per wavelength are obtained for this case on the basis of a first-order estimate for the attenuation coefficient. These results are the same as those derived previously on the basis of model equations for bubbly liquids. They therefore provide additional support for those equations, while indicating some of their limitations.

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Gao, Ying, Apostolos Georgiadis, Niels Brussee, Ab Coorn, Hilbert van der Linde, Jesse Dietderich, Faruk Omer Alpak, et al. "Capillarity and phase-mobility of a hydrocarbon gas–liquid system." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 76 (2021): 43. http://dx.doi.org/10.2516/ogst/2021025.

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When oil fields fall during their lifetime below the bubble point gas comes out of solution. The key questions are at which saturation the gas becomes mobile (“critical gas saturation”) and what the gas mobility is, because mobile gas reduces the production of oil significantly. The traditional view is that the gas phase becomes mobile once gas bubbles grow or expand to a size where they connect and form a percolating path. For typical 3D porous media the saturation corresponding to this percolation limit is on the order of 20%. However, significant literature report on gas mobility below lower limits of percolation thresholds i.e. below 0.1%. A direct experimental insight for that is lacking because laboratory measurements are notoriously difficult since the formation of gas bubbles below the bubble point includes thermodynamic and kinetic aspects, and the pressure decline rates achievable in laboratory experiments are orders of magnitude higher than the decline rates in the field. Here we study the nucleation and transport of gas coming out of solution in-situ in 3D rock using X-ray computed micro tomography which allows direct visualization of the nucleation kinetics and connectivity of gas. We use either propane or a propane–decane mixture as model system and conduct pressure depletion in absence of flow finding that – consistent with the literature – observation of the bubble point in the porous medium is decreased and becomes pressure decline rate dependent because of the bubble nucleation kinetics. That occurs in single-component systems and in hydrocarbon mixtures. Pressure depletion in absence of flow results in critical gas saturations between 20 and 30% which is consistent with typical percolation thresholds in 3D porous structures. That does not explain experimentally observed critical gas saturations significantly below 20%. Also, the respective pore level fluid occupancy where pores are filled with either gas or liquid phase but not partially with both as in normal 2-phase immiscible systems rather diminishes connectivity of gas and liquid phases. This observation indicates that likely other mechanisms play a role in establishing gas mobility at saturations significantly below 20%. Experiments under flow conditions, where gas is injected near the bubble point suggest that diffusion may significantly contribute to the transport of gas and may even be the dominant transport mechanism at field relevant flow rates. The consequence of diffusive transport are compositional gradients where locally the composition is such gas nucleation may occur. That would lead to a disconnected but mobile gas distribution ahead of the convective front. Furthermore, diffusive exchange leads to ripening and anti-ripening effects which influences the distribution for which we see evidence in pressure depletion experiments but not so much at low rate gas injection. Respective relative permeability computed from the imaged fluid distributions using a lattice Boltzmann approach show distinctly different behavior between pressure depletion and flowing conditions. These findings suggest that capillarity in a gas–liquid hydrocarbon mixture is far more complex than in a 2-phase immiscible system. Capillarity is coupled to phase behavior thermodynamics and kinetics on a fast time scale and diffusion-dominated mechanisms such as ripening and anti-ripening effects at a slow time scale. While the consequences for the current experimental and field modelling approaches are not yet fully clear, this shows that more research is needed to fully understand these effects and their implications.

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Matsumoto, Y., and A. E. Beylich. "Influence of Homogeneous Condensation Inside a Small Gas Bubble on Its Pressure Response." Journal of Fluids Engineering 107, no. 2 (June 1, 1985): 281–86. http://dx.doi.org/10.1115/1.3242474.

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The response of a small gas bubble to an ambient pressure reduction is investigated theoretically. Numerical results show that the temperature inside the bubble decreases due to adiabatic expansion at the first stage, then it recovers almost to the surrounding liquid temperature because of latent heat release caused by mist formation inside the bubble. Consequently, the bubble behaves apparently isothermally. The relation between the initial bubble radius and the critical pressure for cavitation inception to stepwise ambient pressure reduction becomes close to the relation under the assumption of isothermal change in the gas mixture inside the bubble.

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Li, Qi Yao, and Ou Yongpeng. "A Numerical Study of the Effect of Bubble Layer on Propulsion Performance of Deep-Vee Hull Form Ship." Advanced Materials Research 479-481 (February 2012): 2551–56. http://dx.doi.org/10.4028/www.scientific.net/amr.479-481.2551.

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A numerical study of the effect of Bubble Layer on Propulsion performance is carried out by using the Air-Liquid Mixture Model. The effect of factors, such as air flow rate, air injected positions on propulsion performance are investigated. The following findings are obtained: (1) In the open water conditions, the air injected inlet is farther away from the propeller center, the little more effect on the propulsion performance; Along with the increase of air flow, the effect of bubbly layer on the propulsion performance increases slightly. (2)Because of the hull form and the clearance between the bottom and the blades tip, bubble layer has small effect on propulsion performance of deep-vee hull form ship propelled by propeller.

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Castro, H. O. S., J. L. Gasche, W. P. Conti, and E. D. R. Vieira. "FLOW PATTERNS OF THE ESTER OIL-REFRIGERANT R134A MIXTURE FLASHING FLOW THROUGH A SMALL DIAMETER TUBE." Revista de Engenharia Térmica 7, no. 1 (June 30, 2008): 41. http://dx.doi.org/10.5380/reterm.v7i1.61740.

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This work presents an experimental investigation of the ester oil ISO VG10-refrigerant R134a mixture flashing flow with foam formation through a straight horizontal 3.22 mm-diameter-6.0 m- long tube. An experimental apparatus was designed to allow the measurement of both pressure and temperature profiles along the tube as well as the visualization of the flow patterns. Tests were performed at different mass flow rates, several refrigerant mass fractions at the inlet of the flow, and inlet mixture temperatures around 28 and 39 °C. A liquid mixture flow with constant temperature and pressure gradient could be noticed at the inlet of the tube. As the flow proceeded towards the exit of the tube the pressure drop produced a reduction of the refrigerant solubility in the oil yielding to formation of the first bubbles. Initially, small and few bubbles could be noticed and the flow behaved as a conventional two-phase flow. Eventually, the bubble population increased and foam flow was observed at the exit of the tube. Due to the great formation of bubbles, both the temperature and pressure gradient of the mixture were greatly reduced in this region of the flow.

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Agisheva, U. O., R. Kh Bolotnova, and M. N. Galimzianov. "Investigation of shock-wave processes in a bubble liquid during the interaction with a barrier." Proceedings of the Mavlyutov Institute of Mechanics 8 (2011): 17–24. http://dx.doi.org/10.21662/uim2011.1.001.

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The parametric analysis the process of reflection a shock wave in a gas-liquid mixture from solid wall is conducted. The results are compared with the experimental data for mixture of water and nitrogen bubbles.

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Ma, Jun-Xian, Xue-Feng Lei, Sha Jiang, Jian-Chun Wang, and Yue-Hui Wang. "Bubble-Liquid Membrane Method for Preparing Spherical Calcium Carbonate Nanoparticles." Journal of Nanoscience and Nanotechnology 21, no. 10 (October 1, 2021): 5241–46. http://dx.doi.org/10.1166/jnn.2021.19332.

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In this work, we describe the principle and operation of a bubble-liquid membrane reactor, and use of the reactor to prepare spherical calcium carbonate nanoparticles. The products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and laser particle size analysis. The effects of additives to control crystal morphology, coating agents, and the stirring speed of the bubble-liquid membrane reactor were investigated. Spherical calcium carbonate nanoparticles with uniform dispersion and no agglomeration were obtained when a disodium hydrogen phosphate/ethylenediaminetetraacetic acid disodium salt mixture (1:1 mass ratio) was used as the additive, oleic acid was used as the coating agent (1.5 wt%), and the stirring speed was 5000–6000 r/min. The results indicate that the bubble-liquid membrane reactor may be suitable for continuous industrial production of calcium carbonate nanoparticles.

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Shalaby, Gamiel, and Ali Abu-Bakr. "Growth of N-dimensional spherical bubble within viscous, superheated liquid: Analytical solution." Thermal Science, no. 00 (2019): 380. http://dx.doi.org/10.2298/tsci190330380s.

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In this paper, we present the study of the bevaiour of spherical bubble in N-dimensions fluid. The fluid is a mixture of vapour and superheated liquid. The mathematical model is formulated in N-dimensions fluid on the basis of continuity and momentum equations, and solved its analytically. The variable viscosity is taken in an account problem. The obtained results show that the radius of bubble increases with the decreasing of the value of N-dimensions.

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EVDOKIMOV, Sergey, Tatyana GERASIMENKO, and Azamat MARZOEV. "APPLICATION OF THE JET SCHEME AND FLOTATION MODE WITH A VAPOR-AIR MIXTURE DURING GOLD-BEARING ORES ENRICHMENT." Sustainable Development of Mountain Territories 13, no. 1 (March 27, 2021): 84–93. http://dx.doi.org/10.21177/1998-4502-2021-13-1-84-93.

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Increasing the economic efficiency of enrichment of refractory gold-bearing ores is possible by reducing the cost of opening sulphide gold-bearing concentrates by reducing the yield of flotation concentrate sent to pyro- or hydrometallurgical processing. It is important to maintain the achieved level of gold recovery into concentrate with a lower concentrate yield. In order to achieve this goal, the gold content in the main flotation operation is increased by mixing the rough concentrate separated from ½ part of the ore feed with another ½ part of it. Mixing in the flotation operation of products with a high level of wash ability (ability to separate) – initial feed and rough concentrate – is identical to an increase in the content of the extractable component in the original ore. In accordance with the new regime of flotation, the process is carried out in cold slurry with bubbles filled with hot steam. The physical basis of the new flotation regime is the dependence of the surface properties of air bubbles and surface forces that determine the stability of the liquid film separating the bubble and the particle on the temperature, which increases due to the heat of the vapor-liquid phase transition. Radial oscillations of the bubble surface as a result of pressure pulsations during condensation and vapor evaporation and surface thermal flows of liquid in the wetting film are factors that provide an increase in the completeness of gold recovery and the selectivity of flotation adhesion obtained in ore flotation experiments. In laboratory conditions, a comparison was made of the indicators obtained during the dressing of gold-bearing ores according to the factory and new schemes. It was revealed that the use of the developed technology allows, with a lower concentrate yield, to obtain an increase of 7.06% abs. extraction of gold into a concentrate of the best quality. A decrease in gold losses with flotation tailings is a consequence of an increase in the number of particles reaching the bubble surface due to radial oscillations of its surface and a weakening of the stability of the wetting film by the thermo-capillary mechanism. An increase in adhesion selectivity can be interpreted using the concept of surface forces of structural origin – an increase in the forces of hydrophobic attraction and hydrophilic repulsion with increasing temperature. The interaction of vapor bubbles with nanobubbles on the surface of the solid phase (wetting by the Cassie-Baxter mechanism) ensures efficient particle recovery by the coalescence mechanism of flotation.

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Paramanantham, SalaiSargunan S., Thanh-Hoang Phan, and Warn-Gyu Park. "Numerical analysis of bubble condensation behavior under high-pressure flow conditions." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, no. 18 (April 8, 2020): 3725–41. http://dx.doi.org/10.1177/0954406220916496.

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Heat transfer during subcooled flow boiling has a pivotal role in pressurized water reactors; it also occurs in boiling water reactors prior to the onset of saturated nucleate boiling. We examined the condensation behavior of vapor bubbles in the subcooled liquid phase using the fully compressible two-phase homogeneous mixture method, solved by an implicit dual-time preconditioned method. The continuous surface force method was applied to determine the surface tension between the phases in the simulation. To predict the empirical coefficient, we conducted a sensitivity study using Lee’s mass transfer model. For nuclear applications, we simulated high-pressure vapor–water conditions under higher mass flow conditions. The comparison of the numerical simulation and experimental results showed that the proposed model accurately predicted the condensation behavior of the bubble. Additionally, we investigated single bubble condensation behavior at different operating pressures, subcooling temperatures, bubble diameters, and bulk velocities. We also investigated the effects of high-pressure condensation on bubble shape. At lower subcooling temperatures, the condensation rate increased as pressure increased; however, at higher subcooling temperatures, pressure had no significant impact on the condensation rate.

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Abdollahzadeh Jamalabadi, Mohammad, Milad Ghasemi, Rezvan Alamian, Somchai Wongwises, Masoud Afrand, and Mostafa Shadloo. "Modeling of Subcooled Flow Boiling with Nanoparticles under the Influence of a Magnetic Field." Symmetry 11, no. 10 (October 11, 2019): 1275. http://dx.doi.org/10.3390/sym11101275.

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Subcooled flow boiling is one of the major issues in the nuclear and power generation industries. If the fluid inlet temperature in the boiling area is less than the boiling temperature, the boiling process is called subcooled boiling. The symmetry of a physical system is a constant property of the system and is fixed by deformation. Using magnetohydrodynamic (MHD) forces and broken symmetry induced by nanosized particles, fluid and thermal systems can be more controlled. In this study, the effect of a magnetic field and nanoparticles on subcooled flow boiling in a vertical tube was investigated. For this purpose, a one-dimensional numerical code was used to simulate the flow and variations of various parameters that have been investigated and evaluated. The results showed that as the flow entered the heated area, the vapor volume fraction, Froude number, fluid cross-sectional area forces, mixture velocity, fluid velocity, bubble departure diameter, liquid and vapor Reynolds numbers, squared ratio of the Froude number to the Weber number, and fluid cross-sectional area forces coefficient increased. In the same region, the Eötvös number, root mean square (RMS) of the fluid cross-sectional area force, sound velocity, liquid superficial velocity, critical tube diameter, bubble departure frequency, and density of the active nucleation site were reduced. It was also observed that after the heated area and under the influence of the magnetic field and the nanoparticles, the values of the vapor volume fraction, Froude number, fluid cross-sectional area force, mixture velocity, fluid velocity, vapor, liquid Reynolds number, and squared ratio of the Froude number to the Weber number were decreased. Moreover, there was no significant effect on the Eötvös number, liquid superficial velocity, Taylor bubble Sauter mean diameter, bubble departure diameter, critical tube diameter, bubble departure frequency, or density of the active nucleation site.

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Kobelev, Yu A., and L. A. Ostrovsky. "Nonlinear acoustic phenomena due to bubble drift in a gas–liquid mixture." Journal of the Acoustical Society of America 85, no. 2 (February 1989): 621–29. http://dx.doi.org/10.1121/1.397586.

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Deng, Xiao Gang, and Xiong Zhou. "The Simulation of the Circumfluence and Inhomogeneous Flow Field in Pulsing Electro-Floatation." Applied Mechanics and Materials 233 (November 2012): 43–46. http://dx.doi.org/10.4028/www.scientific.net/amm.233.43.

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Due to the large-scale violent circumfluence occurred in the traditional electro-floatation (TEF), the interference to the mixture of micro-bubbles and floccules should not be neglected in the floatation. In this paper, the Pulsing Electro-Floatation (PEF) using square wave impulse direct current has been presented. The circumfluence in the inhomogeneous field of the PEF would be gentler than TEF, and the energy utilization rate would be improved. Based the theory of multiphase flow continuous medium, the conservation of momentum equation in the inhomogeneous flow field of PEF has been obtained, and liquid-bubble flow field of the PEF has been simulated using the Fluent module of the ANSYS 13.0. The research result shows that the inhomogeneous flow field in PEF has more reasonable energy distribution, less extent of circumfluence in the process of the micro-bubbles floating, and more benefit for the development and floatation of the bubbles-floccules mixture compared with the TEF. With the same current density, the energy consumption of PEF is 1/4-1/3 that of TEF, but has the similar floatation effect with TEF.

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Kulikov, V. D. "The study of light-scattering intensity on the dew-bubble curve of a binary mixture in the framework of scaling theory." Actual Problems of Oil and Gas, no. 32 (April 21, 2021): 16–25. http://dx.doi.org/10.29222/ipng.2078-5712.2021-32.art2.

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In the framework of scaling theory and the principle of isomorphism of critical phenomena in mixtures, the analytical expression for the light-scattering intensity in a binary fluid mixture has been obtained in rather wide vicinity of its liquid–gas critical point. The deduced validity condition for the light-scattering intensity as an explicit function of temperature or density reveals the adequacy of the description of the obtained experimental data for the methane–pentane binary mixture. The good agreement between the theory and the experiment has been demonstrated. The critical temperature and density values were obtained as a result of optimization procedure.

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Zhong, Chao, Lulu Zhai, Jia Guo, Baoling Cui, and Guoyou Chen. "Static Characteristics and Leakage Rates of Smooth Annular Seals Based on a New Solution Method for Gas-Liquid Two-Phase Conditions." Journal of Marine Science and Engineering 9, no. 5 (May 12, 2021): 523. http://dx.doi.org/10.3390/jmse9050523.

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This paper proposes a new solution method for the leakage and static characteristics of smooth annular seal under a homogeneous gas-liquid two-phase flow based on a bulk-flow model. In this solution method, the Rayleigh–Plesset equation is introduced into the governing equations to describe the behavior of bubbles considering mixture compressibility. Detailed comparisons between Childs’ experimental leakage rates and predicted ones based on the proposed method are conducted, and the predicted results show good agreement with the experimental results, with a maximum error of 11.2%. Moreover, static characteristics of the seal, including leakage rates, gas volume fraction (GVF) distribution, pressure distribution, mixture density, and viscosity within the seals, are investigated based on the present method. The results show that as the inlet gas volume fraction increases from 0% to 10%, the local gas volume fraction of each axial position will increase, however, the seal leakage, mixture density, and mixture viscosity will decrease. Bubble radius has little effect on the leakage rates and the static characteristics of the seals. Additionally, comparisons between the characteristics of the model seals with different clearances show that the leakages of the seals with bigger clearance behave more sensitively to the inlet GVF changes.

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Palencia Muñoz, Miguel Fernando, Natalia Prieto-Jiménez, and Germán González Silva. "Liquid balance - steam for methanol mixing - Benzen using the Peng Robinson and Van-Laar models." Respuestas 24, no. 1 (January 1, 2019): 34–41. http://dx.doi.org/10.22463/0122820x.1807.

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This paper is related to the procedure for calculating curves dew point and bubble point of a binary system, consisting of the methanol and benzene mixture to 45°C, using the Peng-Robinson cubic equation to calculate the fugacity coefficient of gas i in the mixture, and Van Laar model to calculate the activity coefficient of component i in the liquid mixture. Then a comparison between the theoretical data with the experimental data and later with the commercial simulator Hysys-Aspen, which applies the model of Wilson. The simulation was validated with experimental data,in addition to comparing the results with a commercial simulator.

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Tsuda, Shinichi, Takashi Tokumasu, Kenjiro Kamijo, and Yoichiro Matsumoto. "810 Molecular Dynamics Study of Heterogeneous Bubble Nucleation in Binary Mixture Liquid Oxygen." Proceedings of the Fluids engineering conference 2001 (2001): 109. http://dx.doi.org/10.1299/jsmefed.2001.109.

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Journal articles on the topic 'Bubble liquid mixture'

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