Multiphase Medium Research Articles

Використання регулярного теплового режиму для прогнозування інтенсивності теплообміну у відходах птахівництва

The system “environment (water in an annular volume) — a thin cylindrical metal wall — the investigated liquid medium” is being studied. Heat exchange during heating and cooling of water-diluted chicken litter under conditions of forced convection is studied. Chicken droppings represent a multiphase medium, as it consists of solid particles based on a liquid medium. The research is carried out on an experimental stand developed at the Department of Thermal Power Engineering of the National Technical University of Ukraine. Experiments are conducted under conditions of forced convection. Average temperatures are defined as arithmetic averages, based on the results of temperature measurement by thermocouples on vertical thermoprobes at a certain point in time. Processing is carried out by the method of stationary heat exchange, examining the entire period of time. After conducting an analysis of the distribution of excess temperature over time Lnϑ = f(τ) during the study of heat exchange of chicken litter under the conditions of its cooling and heating, a linear rate of cooling/heating m = const was determined, which is characteristic of a regular thermal regime during cooling/heating of a solid body (system of solid bodies) and maintaining the stability of the ambient temperature. It was experimentally established that there is a regular thermal regime in the experimental system: the rate of cooling/heating is constant, m = const; the heat transfer coefficient during the regular thermal regime is practically constant. The coefficient of heat transfer from the inner wall of the cylinder to the studied environment was determined by the method of regular thermal regime and the calculation-experimental method. After analyzing and comparing the heat transfer coefficients calculated using the calculation-experimental method and found by the method of regular thermal regime, a discrepancy of 20 % was established. It was established that, the method of a regular thermal regime can be used to determine the intensity of heat exchange in multiphase media.

Математическая модель двухфазной гиперупругой среды. «Скалярный» случай

The work is devoted to the phenomenological derivation of the multivelocity multifluid model to describe dynamics of the multiphase medium with hyperelastic phase behavior using the Coleman-Noll procedure. The proposed model can be considered as a generalization of the Baer and Nunziato type multiphase models with isotropic stress tensor. The paper presents the well-known particular cases to which the obtained multiphase model can be reduced. The resulting model is completely non-equilibrium, and the joint deformation of the phases is described by a single scalar parameter, which is the volume fraction of the phases.

Influence of the Form of Porous Insert in the Flow of a Viscous Liquid in a Plane Pipe

Filtration of an incompressible liquid (gas) in a non-deformable porous medium is investigated. The results of numerical simulation of the hydrodynamic features of the flow arising after the passage of the liquid through a layer of an immobile porous medium are presented. An interpenetrating model of multiphase media is used to describe such flows. Kozeny-Karman relations are used as the interaction force. The influence of the geometrical shape of the bulk layer on the nature and magnitude of the inhomogeneity of the flow velocity around the obstacle is shown. The shape of the porous medium significantly affects the flow parameters. Numerical simulation results are compared with experimental data. The shape of the porous medium significantly affects the flow parameters. Numerical simulation results are compared with experimental data. The effects of non-uniformity of the fluid velocity field arising due to the shape of the layer surface are investigated by the methods of a computational experiment. A qualitative comparison is made of velocity inhomogeneities when a fluid flows through a porous obstacle. For the numerical implementation of the filtration equation of the interpenetrating model, a SIMPLE-like algorithm was used.

Thermal Instabilities and Shattering in the High-redshift WHIM: Convergence Criteria and Implications for Low-metallicity Strong H i Absorbers

Abstract Using a novel suite of cosmological simulations zooming in on a megaparsec-scale intergalactic sheet (pancake) at z ∼ (3–5), we conduct an in-depth study of the thermal properties and H i content of the warm-hot intergalactic medium (WHIM) at those redshifts. The simulations span nearly three orders of magnitude in gas cell mass, ∼(7.7 × 106–1.5 × 104)M ⊙, one of the highest-resolution simulations of such a large patch of the intergalactic medium (IGM) to date. At z ∼ 5, a strong accretion shock develops around the pancake. Gas in the postshock region proceeds to cool rapidly, triggering thermal instabilities and generating a multiphase medium. We find the mass, morphology, and distribution of H i in the WHIM to all be unconverged, even at our highest resolution. Interestingly, the lack of convergence is more severe for the less-dense, metal-poor intrapancake medium (IPM) in between filaments and far outside galaxies. With increased resolution, the IPM develops a shattered structure with most of the H i in kiloparsec-scale clouds. From our lowest-to-highest resolution, the covering fraction of metal-poor (Z < 10−3 Z ⊙) Lyman-limit systems (N H I > 1017.2cm−2) in the z ∼ 4 IPM increases from ∼(3–15)%, while that of metal-poor damped Lyα absorbers (N H I > 1020cm−2) increases from ∼(0.2–0.6)%, with no sign of convergence. We find that a necessary condition for the formation of a multiphase shattered structure is resolving the cooling length, l cool = c s t cool, at T ∼ 105 K. If this is unresolved, gas “piles up” at T ≲ 105 K and further cooling becomes very inefficient. We conclude that state-of-the-art cosmological simulations are still unable to resolve the multiphase structure of the WHIM, with potentially far-reaching implications.

Survival and mass growth of cold gas in a turbulent, multiphase medium

ABSTRACT Astrophysical gases are commonly multiphase and highly turbulent. In this work, we investigate the survival and growth of cold gas in such a turbulent, multiphase medium using three-dimensional hydrodynamical simulations. Similar to previous work simulating coherent flow (winds), we find that cold gas survives if the cooling time of the mixed gas is shorter than the Kelvin–Helmholtz time of the cold gas clump (with some weak additional Mach number dependence). However, there are important differences. Near the survival threshold, the long-term evolution is highly stochastic, and subject to the existence of sufficiently large clumps. In a turbulent flow, the cold gas continuously fragments, enhancing its surface area. This leads to exponential mass growth, with a growth time given by the geometric mean of the cooling and the mixing time. The fragmentation process leads to a large number of small droplets which follow a scale-free dN/dm ∝ m−2 mass distribution, and dominate the area covering fraction. Thus, whilst survival depends on the presence of large ‘clouds’, these in turn produce a ‘fog’ of smaller droplets tightly coupled to the hot phase which are probed by absorption line spectroscopy. We show with the aid of Monte Carlo simulations that the simulated mass distribution emerges naturally due to the proportional mass growth and the coagulation of droplets. We discuss the implications of our results for convergence criteria of larger scale simulations and observations of the circumgalactic medium.

Cosmic-Ray Transport in Simulations of Star-forming Galactic Disks

Abstract Cosmic-ray transport on galactic scales depends on the detailed properties of the magnetized, multiphase interstellar medium (ISM). In this work, we postprocess a high-resolution TIGRESS magnetohydrodynamic simulation modeling a local galactic disk patch with a two-moment fluid algorithm for cosmic-ray transport. We consider a variety of prescriptions for the cosmic rays, from a simple, purely diffusive formalism with constant scattering coefficient, to a physically motivated model in which the scattering coefficient is set by the critical balance between streaming-driven Alfvén wave excitation and damping mediated by local gas properties. We separately focus on cosmic rays with kinetic energies of ∼1 GeV (high-energy) and ∼30 MeV (low energy), respectively important for ISM dynamics and chemistry. We find that simultaneously accounting for advection, streaming, and diffusion of cosmic rays is crucial for properly modeling their transport. Advection dominates in the high-velocity, low-density hot phase, while diffusion and streaming are more important in higher-density, cooler phases. Our physically motivated model shows that there is no single diffusivity for cosmic-ray transport: the scattering coefficient varies by four or more orders of magnitude, maximal at density n H ∼ 0.01 cm−3. The ion-neutral damping of Alfvén waves results in strong diffusion and nearly uniform cosmic-ray pressure within most of the mass of the ISM. However, cosmic rays are trapped near the disk midplane by the higher scattering rate in the surrounding lower-density, higher-ionization gas. The transport of high-energy cosmic rays differs from that of low-energy cosmic rays, with less effective diffusion and greater energy losses for the latter.

Formulating Multiphase Medium Anti-wetting States in an Air-Water-Oil System: Engineering Defects for Interface Chemical Evolutions.

Studies which regulate macroscopic wetting states on determined surfaces in multiphase media are of far-reaching significance but are still in the preliminary stage. Herein, inspired by the wettability subassembly of fish scales, Namib desert beetle shell, and lotus leaf upper side, interfaces in the air-water-oil system are programmed by defect engineering to tailor the anti-wetting evolution from double to triple liquid repellency states. By controlling the visible light irradiation and plasma treatment, surface oxygen vacancies on CuxO@TiO2 nanowires (NWs) can be healed or reconstructed. The original membrane or the membrane after plasma treatment possesses abundant surface oxygen vacancies, and the homogeneous hydrophilic membrane shows only double anti-wetting states in the water-oil system. By the unsaturated visible light irradiation time, the surface oxygen vacancy partially healed, the heterogeneous hydrophilic-hydrophobic components occupied the membrane surface, and the anti-wetting state finally changed from double to triple in the air-water-oil system. After the illumination time reaches saturation, it promotes the healing of all surface oxygen vacancies, and the membrane surface only contains uniform hydrophobic components and only maintains double anti-wetting state in the air-oil system. The mechanism of the triple anti-wetting state on a heterogeneous surface is expounded by establishing a wetting model. The wetting state and the adhesion state of the CuxO@TiO2 NW membrane show regional specificity by controlling the illumination time and region. The underwater oil droplets exhibit the "non-adhesive" and "adhesive" state in a region with unsaturated irradiation time or in an unirradiated region, respectively. Underwater oil droplet manipulation can be accomplished easily based on switchable wettability and adhesion. Current studies reveal that defect engineering can be extended to anti-wetting evolution in the air-water-oil system. Constructing an anti-wetting interface by heterogeneous components provides reference for designing the novel anti-wetting interface.

Multi-tracer analysis of straight depolarisation canals in the surroundings of the 3C 196 field

Context. Faraday tomography of a field centred on the extragalactic point source 3C 196 with the LOw Frequency ARray (LOFAR) revealed an intertwined structure of diffuse polarised emission with straight depolarisation canals and tracers of the magnetised and multi-phase interstellar medium (ISM), such as dust and line emission from atomic hydrogen (HI). Aims. This study aims at extending the multi-tracer analysis of LOFAR data to three additional fields in the surroundings of the 3C 196 field. For the first time, we study the three-dimensional structure of the LOFAR emission by determining the distance to the depolarisation canals. Methods. We used the rolling Hough transform to compare the orientation of the depolarisation canals with that of the filamentary structure seen in HI, and based on starlight and dust polarisation data, with that of the plane-of-the-sky magnetic field. Stellar parallaxes from Gaia complemented the starlight polarisation with the corresponding distances. Results. Faraday tomography of the three fields shows a rich network of diffuse polarised emission at Faraday depths between − 10 and + 15 rad m−2. A complex system of straight depolarisation canals resembles that of the 3C 196 field. The depolarisation canals align both with the HI filaments and with the magnetic field probed by dust. The observed alignment suggests that an ordered magnetic field organises the multiphase ISM over a large area (~20°). In one field, two groups of stars at distances below and above 200 pc, respectively, show distinct magnetic field orientations. These are both comparable with the orientations of the depolarisation canals in the same field. We conclude that the depolarisation canals likely trace the same change in the magnetic field as probed by the stars, which corresponds to the edge of the Local Bubble.

Simple Method for the Fabrication of Multiple Superwetting Surfaces with Photoresponse.

There have been many studies on special wetting surfaces, but most of them just stay superlyophobic in air or underwater. In this work, a membrane with photoresponse is fabricated by spraying hybrid particles of silicon and titanium dioxide. Under the combined action of hybrid particles and 1H,1H,2H,2H-perfluorodecyltrimethoxysilane, the prepared membrane is superhydrophobic in air. Because of the presence of titanium dioxide, the membrane can realize the transformation from superoleophilic underwater to superoleophobic underwater through UV irradiation and heating. Surprisingly, the membranes with superoleophobicity underwater are also superhydrophobic underoil. Thanks to this unique wettability transition, the prepared membrane can be applied to emulsion separation and fog harvesting. This is inspiring for the preparation and the multifunctional application of multiphase media superlyophobic surfaces.

Mechanism of EDM Intensification at Ultrasound Application

This paper considers some theoretical provisions on the impact ultrasonic mechanical vibrations have on the throughput of an electroerosive piercing of small-diameter holes. The approximate estimates confirm the hypothesis that the cumulative jets mechanism makes the greatest contribution to the intensification of a multiphase medium flow in the interelectrode gap. A model is proposed for a periodic localization of the cavitation region in the bottom part of the annular side gap. It allows explaining the occurrence of a multiphase medium flow during hole processing.

Fractional Modeling and Characteristic Analysis of Hydro-Pneumatic Suspension for Construction Vehicles

The motion differential equation of hydro-pneumatic suspension is established to describe the vibration characteristics for a certain type of construction vehicle. The output force was deduced from the suspension parameters. Based on the suspension characteristics of a multi-phase medium, fractional calculus theory was introduced, and its fractional Bagley–Torvik equation was formed. The numerical computation by a low-pass filter of the Oustaloup algorithm was performed. The numerical solution of a nonlinear fractional equation was obtained to investigate the vibration characteristics of the suspension fractional system. Through the building of an equal-ratio test platform and simulation model, the fractional- integer-order model simulation and experimental data were compared. When the fractional order is 0.9, it better describes the motion characteristics of suspension system. The experiments show that the experimental data can fit the fractional-order system model well, and thereby prove the model on a hydro-pneumatic suspension system.

Cosmological Simulations of Quasar Fueling to Subparsec Scales Using Lagrangian Hyper-refinement

Abstract We present cosmological hydrodynamic simulations of a quasar-mass halo (M halo ≈ 1012.5 M ⊙ at z = 2) that for the first time resolve gas transport down to the inner 0.1 pc surrounding the central massive black hole. We model a multiphase interstellar medium including stellar feedback by supernovae, stellar winds, and radiation, and a hyper-Lagrangian refinement technique increasing the resolution dynamically approaching the black hole. We do not include black hole feedback. We show that the subpc inflow rate (1) can reach ∼6 M ⊙ yr−1 roughly in steady state during the epoch of peak nuclear gas density (z ∼ 2), sufficient to power a luminous quasar, (2) is highly time variable in the pre-quasar phase, spanning 0.001–10 M ⊙ yr−1 on Myr timescales, and (3) is limited to short (∼2 Myr) active phases (0.01–0.1 M ⊙ yr−1) followed by longer periods of inactivity at lower nuclear gas density and late times (z ∼ 1), owing to the formation of a hot central cavity. Inflowing gas is primarily cool, rotational support dominates over turbulence and thermal pressure, and star formation can consume as much gas as provided by inflows across 1 pc–10 kpc. Gravitational torques from multiscale stellar non-axisymmetries dominate angular momentum transport over gas self-torquing and pressure gradients, with accretion weakly dependent on black hole mass. Subpc inflow rates correlate with nuclear (but decouple from global) star formation and can exceed the Eddington rate by ×10. The black hole can move ∼10 pc from the galaxy center on ∼0.1 Myr. Accreting gas forms pc-scale, rotationally supported, obscuring structures often misaligned with the galaxy-scale disk. These simulations open a new avenue to investigate black hole–galaxy coevolution.

Fractal Properties of a Falling Particle Curtain in Air

Abstract The formation of a gravity-driven falling particle curtain is important for many problems, including solar tower particle receivers and setting the correct initial conditions for modeling shock interaction with multiphase media. One important characteristic of the curtain is the time history of its fractal dimension that characterizes the evolutionary growth of perturbations along the curtain's extent. For multiphase flows, fractal dimension can be used to help predict the types of instabilities that will occur within the flow. Our experiment aimed to establish the transient and stationary-value fractal dimension of a dense particle curtain with varying thickness containing particles with a density of 1.44 gm/cm3 and nominal diameter of 40 μm. High-speed video of the curtain was captured and analyzed. This data from this experiment, besides providing insights into the relevant physical processes, will be used to validate numerical models for multiphase flows.

Improving the mechanical-mathematical model of pneumatic vibration centrifugal fractionation of grain materials based on their density

This paper has substantiated the mechanical-mathematical modeling of the process of fractionation of grain material into fractions. It has been established that this could optimize the process parameters and would make it possible to design new or improve existing working surfaces of centrifugal separators. A mechanical-mathematical model of the pneumatic vibratory centrifugal separation of grain material by density has been improved. This research is based on the method of hydrodynamics of multiphase media. The improved mechanical-mathematical model takes into consideration the interaction between the discrete and continuous phases of grain material by introducing conditions of interaction at the interface of these phases. In the hydrodynamic modeling of the movement of the circular layer of seeds, the coefficient of dynamic viscosity of discrete and continuous phases was taken into consideration. It was established that the pneumatic vibratory centrifugal separation process parameters are critically affected by the circular frequency of rotation of the cylindrical working surface, the frequency and amplitude of its oscillations. As well as such process characteristics as the airflow rate, dynamic viscosity coefficient, the average thickness of a grain material layer, and the mean density of its particles. Rational values for the technical parameters of the grain material pneumatic vibratory centrifugal fractionation process in terms of density have been determined by using the improved mechanical-mathematical model. The amplitude and oscillation frequency of the working surface are in the ranges A=(35…50)·10–5 m, ω=15.0...15.6 rad/s. The circular rotation frequency of the working surface, ω=24...25 rad/s. The airflow rate, V=2 m/s. It was established that using the improved mechanical-mathematical model of fractionation makes it possible to improve the performance of a pneumatic vibratory centrifugal separator by 9 %. At the same time, the effectiveness of grain material separation could reach 100 %.

Investigation of boiling heat transfer for improved performance of metal hydride thermal energy storage

The inherent nature concerning the intermittency of concentrating solar power (CSP) plants can be overcome by the integration of efficient thermal energy storage (TES) systems. Current CSP plants employ molten salts as TES materials although metal hydrides (MH) have proven to be more efficient due to their increased operating temperatures. Nonetheless, the heat exchange between the MH bed and the heat transfer medium used to operate a heat engine is a critical factor in the overall efficiency of the TES system. In this work, a computational study is carried out to investigate the performance of a magnesium hydride TES packed bed using a multiphase (boiling) medium instead of single-phase heat absorption methods. The boiling heat transfer behaviour is simulated by using the Eulerian two-fluid framework. The simulations are conducted at a transient state using SST-k-ω Reynolds-Averaged Navier-Stokes equations. It is observed that, unlike the single-phase heat collection method, the multiphase heat absorption method maintains a constant temperature in the heat transfer fluid throughout the reactor. Consequently, a higher temperature gradient is realised between the MH bed and heat transfer fluid (HTF), leading to improvements in the overall reaction rate of the hydrogenation process.

Preface

The XXII-th Winter School on Continuous Media Mechanics, a scientific event traditionally organized by the Institute of Continuous Media Mechanics Ural Branch of the Russian Academy of Sciences. It is a biennial meeting, which attracts researchers in the field of mechanics. The School was approved the Russian National Committee for Theoretical and Applied Mechanics, the Scientific Council of the Russian Academy of Sciences on mechanics of deformable solids of the Urals Branch of the Russian Academy of Sciences, the Technical Committee 17 (Non-Destructive Assessment) of the European Society for Structural Integrity (ESIS), and the Russian Committee of ESIS.The Schools are also attended by our foreign colleagues, who are involved in active collaboration with the scientists of the Institute. About 370 people from 9 countries (Russia, Germany, France, Israel, Italy, USA, China, UK, Azerbaijan) took part in the XXII Winter School on Continuum Mechanics. Russian participants represented 50 organizations in 15 cities (Perm, St. Petersburg, Moscow, Yekaterinburg, Krasnoyarsk, Novosibirsk, Kazan, Samara, Rostov-on-Don, etc.). Most participants are regular attendees of this scientific event. The Scope of the Conference traditionally covers the following topics:– physics and mechanics of meso- and nano-structured systems– convection, hydrodynamic stability and turbulence– hydrodynamics of multiphase media– hydrodynamics of non-Newtonian liquids and liquids with special characteristics– computational continuum mechanics– coupled problems of solid mechanics– interdisciplinary studies– mining mechanics.During the conference reports were made on fundamental and applied problems of physics and continuum mechanics, including 20 invited reports (45 minutes) of well-known experts in the relevant branches of physics and mechanics (academicians, corresponding members of the Russian Academy of Sciences, doctors of science).All the participants had 15 minutes to present their latest academic research findings one by one. Besides, there was a Q&A discussion after every of 342 presentation.Due to the severe impact of the COVID-19 outbreak and travel restrictions, it has been difficult for authors to attend the offline meeting. Therefore, the XXII-th Winter School on Continuous Media Mechanics virtual conference is a better way to achieve the goal of ensuring the safety and health of all participants. The conference was conducted virtually through the platform “Big Blue Button”. Before the official meeting, the organizing committee has opened a test room for all keynote speakers and authors to test the platform whether the operation is normal or not. The plenary reports were broadcast simultaneously on YouTube. 5-6 sections were working at the same time. The total number of views of the plenary lectures on Youtube during the School’s work reached 954, and on Big Blue Button-726. On average, 100 to 175 people were connected to the Big Blue Button platform during the breakout sessions. The participants of the School note the high scientific level, the good organization and intensity of the work, the relevance of the plenary and oral reports, the possibility of a broad and in-depth discussion of the issues presented in the program by specialists in various areas of physics and continuum mechanics. This issue contains articles on the part of the reports presented at the School. After the detailed reviewing, we have accepted 73 submissions.List of Program Committee, Organizing Committee are available in this pdf.

Features of modeling multiphase media in problems of electromagnetic generation of flows

The study of the electromagnetic force acting on a medium with inhomogeneous electrical conductivity has been carried out. The electrical conductivity changes abruptly which simulates the liquid–solid interface during the crystallization of a pure metal. The electromagnetic force is created by a traveling field inductor with one of the most demanded in metallurgy construction. The results showed a significant dependence of the electromagnetic force on the position of the interface with respect to the inductor. Consequently in the mathematical modeling of the directional crystallization process under the influence of an electromagnetic force created by an inductor of this type it is necessary during the movement of the interface, either to do the calculation of the electrodynamic part of the problem anew or to use the method of canonical domains.

XII Scientific Technical Conference On Low Temperature Plasma During The Deposition Of Functional Coatings

In the city of Kazan from November 10 to November 12, 2020 on the basis of the Kazan Federal University hosted the XII Scientific Technical Conference on Low Temperature Plasma during the Deposition of Functional Coatings.One of the main tasks of the conference is to discuss and develop the fundamental principles of plasma deposition of functional coatings. Conference papers were presented in the following areas:– Physics of gas discharge;– Physical processes in low-temperature plasma when applying functional coatings;– Thermodynamic, portable and optical properties of low-temperature plasma in coating processes;– Interaction of plasma and high-energy ion beams with a solid;– Combustion processes and heat and mass transfer in multiphase media;– Dusty plasma;– Plasma chemistry. Electrochemistry;– Diagnostics of low-temperature plasma;– Characteristics of coatings obtained using low-temperature plasma;– Application of ion-plasma coatings.Within the framework of the conference, a school for young scientists is held, lectures by leading scientists and specialists in the field of low-temperature plasma application are held.Gas-discharge plasma is widely used in various fields of science and technology. Plasma is used in industry, medicine, ecology and is the basis of various devices and technologies, for example, it is used in the technology of applying functional coatings.The friendly atmosphere at the XII Scientific Technical Conference on Low Temperature Plasma during the Deposition of Functional Coatings allowed it to become an excellent platform for the exchange of experience and generation of new ideas in the field of physics and the use of low-temperature plasma.List of Organizing Committee are available in this pdf.

Capillary-absorbed moisture transfer in a multiphase soil medium considering the load potential

The work presents an analytical solution to the equation of moisture permeability of structural varieties of capillary-absorbed moisture in a multiphase soil system with incomplete water saturation considering the influence of load potential. Researches were carried out and the influence of external load on the moisture profile in a multiphase system, the rate of moisture transfer of a discontinuous flow in general, and the rate of moisture propagation of the wetting boundaries have been shown. For a comparative analysis of the indicators of moisture transfer, functional relationships between the potential and pressure of the structural varieties of capillary-absorbed ground moisture are presented: capillary-gravity, proper-capillary and capillary-osmotic components of ground moisture. In the interval of incomplete water saturation, an attempt was made to create the foundations of capillary moisture transfer in the soil environment considering both the external distributed load and the own weight of the soil.

The Source of Leaking Ionizing Photons from Haro11: Clues from HST/COS Spectroscopy of Knots A, B, and C*

Abstract Understanding the escape of ionizing (Lyman continuum) photons from galaxies is vital for determining how galaxies contributed to reionization in the early universe. While directly detecting the Lyman continuum from high-redshift galaxies is impossible due to the intergalactic medium, low-redshift galaxies in principle offer this possibility but require observations from space. The first local galaxy for which Lyman continuum escape was found is Haro 11, a luminous blue compact galaxy at z = 0.02, where observations with the FUSE satellite revealed an escape fraction of 3.3%. However, the FUSE aperture covers the entire galaxy, and it is not clear from where the Lyman continuum is leaking out. Here we utilize Hubble Space Telescope/Cosmic Origins Spectrograph spectroscopy in the wavelength range 1100–1700 Å of the three knots (A, B, and C) of Haro 11 to study the presence of Lyα emission and the properties of intervening gas. We find that all knots have bright Lyα emission. UV absorption lines, originating in the neutral interstellar medium, as well as lines probing the ionized medium, are seen extending to blueshifted velocities of 500 km s−1 in all three knots, demonstrating the presence of an outflowing multiphase medium. We find that knots A and B have large covering fractions of neutral gas, making LyC escape along these sightlines improbable, while knot C has a much lower covering fraction (≲50%). Knot C also has the the highest Lyα escape fraction, and we conclude that it is the most likely source of the escaping Lyman continuum detected in Haro 11.