Fluid Dispersion Research Articles

Computational analysis of ternary nanofluid flow in a microchannel with nonuniform heat source/sink and waste discharge concentration

The investigation of waste discharge concentration with microchannel plays a significant impact on environmental applications. Microchannels are utilized in treatment facilities for wastewater to manage the concentration of pollutants and impurities. Effective waste treatment and pollution control techniques may be created by investigating waste material’s fluid flow and dispersion in microchannels. In view of the above applications, the present investigation examines the electrically conducting and incompressible ternary hybrid nanofluid movement in a microchannel with a nonuniform heat source/sink and waste discharge concentration. The governing equations are converted into a system of ordinary differential equations using appropriate similarity constraints, and the resulting equations are numerically solved using the RKF-45 (Runge Kutta Fehlberg 4th and 5th) method. The effects of different nondimensional limitations are visually displayed and thoroughly explored on flow patterns, heat distribution, and concentration profiles. The analysis is done on important engineering variables such as skin friction, heat transfer rate, and mass transfer. Magnetic and porous media shape factors directly influenced the velocity and temperature profiles. These two factors will decline the velocity and improve the temperature. Further, the improvement in local and external pollutant concentration will improve the concentration of the fluid. The rate of mass transfer improves with increasing the local external source constraint. The present work outcomes are helpful in heat exchangers, pollution control, microfluidic chip devices, wastewater treatment, and energy conversion.

Nano- and Microemulsions in Biomedicine: From Theory to Practice.

Nano- and microemulsions are colloidal systems that are widely used in various fields of biomedicine, including wound and burn healing, cosmetology, the development of antibacterial and antiviral drugs, oncology, etc. The stability of these systems is governed by the balance of molecular interactions between nanodomains. Microemulsions as a colloidal form play a special important role in stability. The microemulsion is the thermodynamically stable phase from oil, water, surfactant and co-surfactant which forms the surface of drops with very small surface energy. The last phenomena determines the shortage time of all fluid dispersions including nanoemulsions and emulgels. This review examines the theory and main methods of obtaining nano- and microemulsions, particularly focusing on the structure of microemulsions and methods for emulsion analysis. Additionally, we have analyzed the main preclinical and clinical studies in the field of wound healing and the use of emulsions in cancer therapy, emphasizing the prospects for further developments in this area.

Solute dispersion of Hershel-Bulkley fluid through an inclined artery

Different types of arteries in the human body possess inclinations that impact blood flow behavior and affect the effectiveness of medical treatments, such as intra-arterial injections that rely on accessing the bloodstream through these arteries. Hence, this present study analyses the behavior of blood flow and solute dispersion in an inclined artery while considering the Herschel-Bulkley model representing the blood rheology to investigate the influence of arterial inclination. The solutions for flow velocity and solute concentration are solved using the integration method. The Taylor-Aris method has been implemented to obtain effective axial and relative axial diffusion. This research investigates the impact of artery inclination on blood flow, solute dispersion characteristics (flow velocity, solute concentration, and axial diffusions), as well as explores the influence of gravitational acceleration on blood flow and solute dispersion behaviors. Results show that the angle of artery inclination directly influences the gravitational acceleration effect which correlates to the resulting flow velocity and solute dispersion. 90o and 270o inclination angle has the highest effect in increasing and decreasing the flow velocity, solute concentration and diffusions respectively. Meanwhile, 0o, 180o and 360o eliminate the gravitational acceleration effect on the flow behavior and dispersion process.

Modeling the rheological properties of plant‐based foods: Soft matter physics principles

AbstractThere is growing interest in the design and fabrication of next‐generation plant‐based (NG‐PB) foods that have physicochemical and functional properties that simulate those of traditional animal‐based foods, like meat, seafood, egg, and dairy products. Many of these products are colloidal materials containing particles or polymers, which means that their properties can be understood using soft matter physics concepts. The rheological properties of NG‐PB foods may vary widely, including low‐viscosity fluids (like milk), high‐viscosity fluids (creams), soft solids (like yogurt), and hard solids (like some cheeses). For manufacturers of NG‐PB foods to mimic this broad range of products it is important to have theoretical models to identify, predict, and control the key parameters impacting their textural attributes. In this article, the theoretical models developed to describe the properties of fluid, semi‐solid, and solid colloidal dispersions are summarized, and their potential for improving the design and fabrication of NG‐PB foods is highlighted. In the future, it will be important to establish the most appropriate models for different categories of NG‐PB foods and to determine their range of applications.

Development of a scale-up strategy for an aerated coaxial mixer containing a non-Newtonian fluid: A mass transfer approach

Coaxial mixers have been shown to be effective in enhancing the hydrodynamic stress and shear environment inside the aerated systems. However, the scale-up study of the aerated coaxial mixing reactors based on a constant mass transfer coefficient has never been reported in the literature. In this study, for the first time, a practical technique is suggested to evaluate the scalability of these systems in terms of a constant mass transfer coefficient. The effects of impeller speed, impeller type, aeration rate, and pumping direction on the mass transfer, power consumption, gas holdup profile, fluid hydrodynamics, and energy dissipation rate were explored for gas dispersion in non-Newtonian fluids inside coaxial mixers through tomography, dynamic gassing-in, and computational fluid dynamics. It was found that a practical approach to preserve the mass transfer coefficient of the large-scale coaxial mixer the same as its small-scale counterpart was to maintain the volumetric aeration rate per working fluid volume constant.

Investigating the power consumption for the intensification of gas dispersion in a dual coaxial mixer containing yield-pseudoplastic fluids

Coaxial mixers with double central impellers and an anchor have demonstrated promising results in the intensification of gas dispersion in complex fluids. While previous studies have evaluated power consumption for gas dispersion in pseudoplastic fluids, no investigation has been conducted on aerated dual coaxial mixers containing pseudoplastic fluids with yield stress. This study aimed to evaluate the power consumption of the aerated double coaxial mixer under various operating conditions, including anchor and central impeller speed, rotational mode, pumping direction, and aeration rate. Experimental power consumption measurements were performed for both gassed and ungassed systems. Our findings showed that the anchor power contributed substantially less to overall power consumption than the central impellers. The counter-rotational mode used more power than the co-rotational mode due to the opposing flow created by the rotation of the central impellers and anchor impeller. The co-rotational mode had a higher relative power demand (RPD) than the counter-rotational mode, with the upward pumping mode of the central impellers yielding the highest RPD values. The modified Jamshidzadeh's correlation successfully predicted the impact of the anchor speed, central impeller speed, and aeration rate on power consumption for the investigated double coaxial mixers containing the xanthan gum solution.

Thermal characterization of heat source (sink) on hybridized (Cu–Ag/EG) nanofluid flow via solid stretchable sheet

Abstract The goal of this research is to consider the thermal impact on varied convection flow in hybrid nanofluids with heat generation over a two-dimensional heated flat around a stretchable sheet. The flow is considered steady and incompressible while the stretchable sheet is assumed an impermeable. Two distinctive nano-level particles are considered, namely copper (Cu) and silver (Ag) with ethylene glycol base fluid. The boundary layer was generated on a stretchable sheet surface by mixed convection flow in hybrid nanofluids. Ideally, the sink and source are thermal reservoirs of internal thermal capacities. This means you can extract or reject heat from them without changing their temperature. To make a study of thermodynamic systems like heat engines and refrigerator systems, the governing equations were solved numerically with Keller-box methodology depending on the implicit finite-difference technique. Research findings were worked with the parameters of mixed convection, Prandtl number, nanoparticle volume fraction, through various non-dimensional parameters, and heat generation. Especially for thermal generation enhancement, the fluidity and thermal dispersal get elevated. Even though the flowing behavior and the thermal dispersal of hybridity fluids with the combinations of Cu and Ag nanoparticles were similar, their values are distinct, which reflect in graphical displays. The hybrid nanofluidity gets improved with the volume variation of nanoparticles if the ϕ \phi value is 0.01 ≤ ϕ ≤ 0.05 0.01\le \phi \le 0.05 and if the flow profile value decreases ϕ h {\phi }_{{\rm{h}}} , where 0.01 ≤ ϕ h ≤ 0.05 0.01\le {\phi }_{{\rm{h}}}\le 0.05 as the dispersal of temperature enhances when the nanoparticle nanofluid constraint is improved.

Derivation of acoustical streaming equations for nonlinear and dispersive fluids

The equations of streaming generated by an acoustic mod propagating in a nonlinear dispersive medium (exhibiting absorption and dispersion of phase sound speed) are derived with an arbitrarily shaped incident acoustical field assumed. This field may be periodic or non-periodic. A general dispersion model represented by a convolution operator taking into account relaxation effects was taken into account. Making the assumption of a periodic acoustic field from the general streaming equation.The quasi-stationary flow is driven by a force given by the average value of the dispersion operator with respect to the velocity and acoustic pressure fields. In the spectral representation, it is given by the weighted spectral power density distribution of the acoustic field. The weight of the distribution is the dispersion coefficient - the eigenvalue of the dispersion operator. A new result also reveals the effect of the refractive index deviation on the driving force of streaming. The possibility of generalizing the description of streaming in the simplest case of a non-Newtonian fluid was analyzed. The Reiner-Revlin model of a simple liquid was assumed. It was also noted that the streaming model in the Maxwell liquid is analytically solvable. It was found that asymptotic states of streaming in this model and the Navier-Stokes model are identical.The derivations use new methods different from those used so far. They are based on the separation of nonlinear modes in the momentum transport equation and on the properties of the Gauss-Weierstrass function for the Fick diffusion operator. So far, the method of successive approximations has been used. The consistency of the obtained equations with the assumptions was checked. The obtained formulas generalize the known descriptions of the form of forces driving streaming and extend their application to the case of nonlinear propagation.

Influence of 4 drain configurations on fluid dispersal and retrieval in an instillation model

To describe and compare the pattern of fluid dispersal and retrieval in a novel instillation therapy system. In vitro experimental study. A 10 cm2 square model was constructed using plastic sheeting secured to plexiglass, with a wound infusion catheter and Jackson-Pratt (JP) active suction drain positioned in 4 configurations: parallel, perpendicular, diagonal, and opposite. Fluid was instilled using the wound infusion catheter, allowed to dwell for 10 min, and retrieved using the JP drain. Two surface area calculations were made using imaging software: coloration with diluted methylene blue (MB) on photos, and filling with diluted contrast on fluoroscopic images. Fluid retrieval was recorded. Statistical analysis was performed using a mixed-effects linear model (p < .05). Configuration influenced fluid dispersion within the model (p=.0001); the diagonal configuration had the greatest surface area coverage (mean ± SD; 94.5 ± 2.4%) and the parallel configuration had the lowest surface area coverage (60.2 ± 2.9%). A dwell period increased fluid dispersal by an average of 4.0 ± 0.8% (p < .0001). Fluid retrieval exceeded 16.7 ± 1.5 mL (83.5 ± 7.5% volume instilled) for all configurations and was 0.5 ± 0.1 mL (2.5 ± 0.5% volume instilled) greater for MB than contrast agent (p < .0001). Perpendicular or diagonal configurations and low-viscosity fluid maximized fluid dispersion and retrieval. Wound instillation therapy involves delivering lavage fluid or medications to a closed wound space. This is feasible using a wound-infusion catheter and active suction drain. Configuration should be considered to optimize fluid dispersal and retrieval when planning instillation therapy.

A numerical investigation to determine longitudinal dispersion coefficient in ideal and randomized reticulated porous structures using transient direct pore level simulation

The purpose of this numerical investigation is to characterize the longitudinal dispersion coefficients in open-cell reticulated porous structures. Open-cell foams are modelled using idealized Kelvin cell structures. Using the conventional Navier–Stokes equation, airflow has been calculated through various porous structures. Along with the flow, the dispersion of a tracer fluid is traced across the structures and analyzed in terms of the effective dispersion coefficient. Using direct pore level simulations (DPLS), a parametric study is performed to understand the influence of geometrical parameters on the dispersion in porous media. To evaluate the longitudinal dispersion coefficient (LDC), the analytic solution gradients were fitted into the simulated gradients. From the results, a new characteristic length correlation is proposed to calculate the Peclet number, and it is compared with experimental and numerical data that are available in the literature.

Functional Nanocomposites in the Development of Flexible Armor

The idea of flexible body armor has been around for many years. Initial development included shear thickening fluid (STF) as a backbone polymer to impregnate ballistic fibers such as Kevlar. At the core of the ballistic and spike resistance was the instantaneous rise in viscosity of STF during impact. Increase in viscosity was due to the hydroclustering of silica nanoparticles dispersed in polyethylene glycol (PEG) through a centrifuge and evaporation process. When STF composite was dry, hydroclustering was not possible due to absence of any fluidity in PEG. However, particles embedded within the polymer, covered the Kevlar fiber and offered some resistance to spike and ballistic penetration. The resistance was meagre and hence, the goal was to improve it further. This was achieved by creating chemical bonds between particles, and by strongly attaching particles to the fiber. PEG was replaced with silane (3-amino propyl trimethoxysilane), and a fixative cross-linker, Glutaraldehyde (Gluta), was added. Silane installed an amine functional group on the silica nanoparticle surface, and Gluta created strong bridges between distant pairs of amine groups. Amide functional groups present in Kevlar also interacted with Gluta and silane to form a secondary amine, allowing silica particles to attach to fiber. A network of amine bonding was also established across the particle-polymer-fiber system. In synthesizing the armor, silica nanoparticles were dispersed in a mixture of silane, ethanol, water, and Gluta, maintaining an appropriate ratio by weight, and using a sonication technique. Ethanol was used as a dispersion fluid and was evaporated later. Several layers of Kevlar fabric were then soaked with the admixture for about 24 h and dried in an oven. Armor composites were tested in a drop tower according to NIJ115 Standard using spikes. Kinetic energy at impact was calculated and normalized with the aerial density of the armor. NIJ tests revealed that normalized energy for 0-layer penetration increased from 10 J-cm2/g (STF composite) to 220 J-cm2/g for the new armor composite, indicating a 22-fold enhancement. SEM and FTIR studies confirmed that this high resistance to spike penetration was due to the formation of stronger C-N, C-H, and C=C-H stretches facilitated by the presence of silane and Gluta.

Non‐Isothermal Mass Transfer in Fluid Drops with Internal Circulation

AbstractThe influence of internal circulation on the heat and mass transfer within dispersed fluid drops in translation was studied numerically using the computational fluid dynamics simulation tool ANSYS FLUENT. The three phases identified for heat/mass transfer are: the initial and final diffusion‐dominated phases and a middle convection‐dominated phase. Non‐isothermal mass transfer simulations using temperature‐dependent diffusion coefficients were carried out to investigate the influence of heating and cooling of the drop on the solute transfer. Mass transfer is slower compared to heat transfer and the final diffusion‐dominated mass transfer occurs at the final temperature attained by the drop. Mass transfer is faster for drop heating than for drop cooling, as the final diffusion phase is rate controlling and significant solute transfer occurs at the final higher temperature.

Wave propagation and stabilization in the Boussinesq–Burgers system

This paper considers the existence and stability of traveling wave solutions of the Boussinesq–Burgers system describing the propagation of bores. Assuming the fluid is weakly dispersive, we establish the existence of three different wave profiles by the geometric singular perturbation theory alongside phase plane analysis. We further employ the method of weighted energy estimates to prove the nonlinear asymptotic stability of the traveling wave solutions against small perturbations. The technique of taking antiderivative is utilized to integrate perturbation functions because of the conservative structure of the Boussinesq–Burgers system. Using a change of variable to deal with the dispersion term, we perform numerical simulations for the Boussinesq–Burgers system to showcase the generation and propagation of various wave profiles in both weak and strong dispersions. The numerical simulations not only confirm our analytical results, but also illustrate that the Boussinesq–Burgers system can generate numerous propagating wave profiles depending on the profiles of initial data and the intensity of fluid dispersion, where in particular the propagation of bores can be generated from the system in the case of strong dispersion.

Ultrasonic surface acoustic wave-assisted separation of microscale droplets with varying acoustic impedance.

In droplet-based microfluidic platforms, precise separation of microscale droplets of different chemical composition is increasingly necessary for high-throughput combinatorial chemistry in drug discovery and screening assays. A variety of droplet sorting methods have been proposed, in which droplets of the same kind are translocated. However, there has been relatively less effort in developing techniques to separate the uniform-sized droplets of different chemical composition. Most of the previous droplet sorting or separation techniques either rely on the droplet size for the separation marker or adopt on-demand application of a force field for the droplet sorting or separation. The existing droplet microfluidic separation techniques based on the in-droplet chemical composition are still in infancy because of the technical difficulties. In this study, we propose an acoustofluidic method to simultaneously separate microscale droplets of the same volume and dissimilar acoustic impedance using ultrasonic surface acoustic wave (SAW)-induced acoustic radiation force (ARF). For extensive investigation on the SAW-induced ARF acting on both cylindrical and spherical droplets, we first performed a set of the droplet sorting experiments under varying conditions of acoustic impedance of the dispersed phase fluid, droplet velocity, and wave amplitude. Moreover, for elucidation of the underlying physics, a new dimensionless number ARD was introduced, which was defined as the ratio of the ARF to the drag force acting on the droplets. The experimental results were comparatively analyzed by using a ray acoustics approach and found to be in good agreement with the theoretical estimation. Based on the findings, we successfully demonstrated the simultaneous separation of uniform-sized droplets of the different acoustic impedance under continuous application of the acoustic field in a label-free and detection-free manner. Insomuch as on-chip, precise separation of multiple kinds of droplets is critical in many droplet microfluidic applications, the proposed acoustofluidic approach will provide new prospects for microscale droplet separation.

The effect of microparticles/nanoparticles surface modification on the magnetorheological fluid properties: A review

Magnetorheological fluids are considered smart materials since their properties change significantly when exposed to a magnetic field, making them interesting for a variety of industries. These fluids are composed of three main components: dispersed particles, carrier fluid, and additives. The latter of which has been the subject of various studies. Therefore, this paper reviews the characteristics and parameters of the particles dispersed in additives and their impact on fluid rheological properties and stability. Also, the surface modification of magnetic and non-magnetic micro and nanoparticles have been investigated. A detailed review of previous studies has been carried out to examine the effects of various parameters such as types of coatings, coating layers, coating thickness, density change, and change in magnetic saturation, on the stability and rheological properties of MR fluids.

Intensified gas-liquid mixing in bioreactors equipped with a dual coaxial mixer containing biopolymer solutions

One of the significant challenges in the efficient operation of bioreactors is uniform gas dispersion in very viscous non-Newtonian fluids because of the complex rheology exhibited by these fluids. The uneven gas distribution is more pronounced when large-scale aerated bioreactors with aspect ratios of higher than one are utilized. Prior studies have shown that using a close clearance anchor and two centrally positioned impellers in gas-liquid coaxial mixers can improve gas dispersion in pseudoplastic fluids. Nonetheless, despite the extensive applications of yield-pseudoplastic fluids in many industries, no research has been conducted on the gas dispersion in yield-pseudoplastic fluids within a dual coaxial bioreactor with a greater-than-one aspect ratio. In this regard, electrical resistance tomography (ERT) and computational fluid dynamics (CFD) were employed to assess the effect of operating parameters, namely central impeller speed, anchor speed, aeration rate, rotating mode, and pumping mode of central impeller on the aeration efficiency in yield-pseudoplastic fluids. The experimental measurement of the overall gas hold-up affirmed the profound impact of using a close clearance anchor. Even though the down-pumping and co-rotational mode at Na = 30 rpm provided the highest aeration efficiency, more uniform gas dispersion was observed at Na = 10 rpm owing to a greater axial velocity in the downward direction and more effective circulation loops. Compared to the downward pumping direction, lower gas hold-up values were obtained for the up-pumping configurations. Finally, the superiority of the down-pumping and co-rotational mode was demonstrated by comparing the aeration efficiency of various mixing configurations.

The weakly non-linear waves propagation for Kelvin-Helmholtz instability in the magnetohydrodynamics flow impelled by fractional theory.

The weakly nonlinear wave propagation that occurs in the presence of magnetic fields, in which energy is concentrated in a narrow band of wave-numbers in a dispersive and dissipative fluid. The main objective of this paper is to analyze the dimensional elliptic nonlinear Schrodinger equation under the influence of three different fractional operators. The generalized fractional soliton solutions and propagation of magnetohydrodynamics fluid in sort of solition will be visualized. The Conformable, and M-truncated fractional operator applied to classical evolution Schrodinger equation. In order to get the analytical closed form solution, one of the generalized approach new extended direct algebraic method is utilized. The fractional nonlinear elliptic Schrodinger equation is developed in three different fractional sense. The similarity transformation technique converted the controlling fractional system to ordinary differential equations. The fractional analytical solutions such as, plane solution, mixed hyperbolic solution, periodic and mixed periodic solutions, mixed trigonometric solution, trigonometric solution, shock solution, mixed shock singular solution, mixed singular solution, complex solitary shock solution, singular solution and shock wave solutions are obtained. The graphical 2-D and 3-D representation of the results is shown to express the propagation of fluid with the magnetic field by assuming the appropriate values of the involved parameters. The graphical performance of the obtained solution at various settings of parametric values and fractional order reveals new perspectives and fascinating model phenomena. The attained outcomes have significant applications and have opened up innovative development areas for research across numerous scientific fields.

Whitham modulation theory of defocusing nonlinear Schrödinger equation and the classification and evolutions of solutions with initial discontinuity

Since the Whitham modulation theory was first proposed in 1965, it has been widely concerned because of its superiority in studying dispersive fluid dynamics and dealing with discontinuous initial value problems. In this paper, the Whitham modulation theory of the defocusing nonlinear Schrödinger equation is developed, and the classification and evolution of the solutions of discontinuous initial value problem are studied. Moreover, the dispersive shock wave region, the rarefaction wave region, the unmodulated wave region and the plateau region are distinguished. Particularly, the correctness of the results is verified by direct numerical simulation. Specifically, the solutions of 0-phase and 1-phase and their corresponding Whitham equations are derived by the finite gap integration method. Also the Whitham equation of genus &lt;i&gt;N &lt;/i&gt;corresponding to the &lt;i&gt;N&lt;/i&gt;-phase periodic wave solution is derived. The basic structures of rarefaction wave and dispersive shock wave are given, in which the boundaries of the regions are calculated in detail. The Riemann invariants and density distributions of dispersive fluids in each case are discussed. When the initial value is fixed as a special one, the vacuum point is considered and analyzed in detail. In addition, the oscillating front and the soliton front in the dispersive shock wave are considered. In fact, the Whitham modulation theory has many wonderful applications in real physics and engineering. The dam problem is investigated as a special Riemann problem, the piston problem of dispersive fluid is analyzed, and the novel undular bores are found.

The Interference of Monoclonal Anti-Cluster of Differentiation 47 on Transfusion Compatibility Testing

Hu5F9-G4 and AK117, novel cluster of differentiation 47 blockers, are used to treat solid tumors and hematoma. Because cluster of differentiation 47 is expressed on erythrocytes, treatment with monoclonal anti-cluster of differentiation 47 may interfere with the results of transfusion compatibility testing. This study analyzed the interference and treatment of Hu5F9-G4 and AK117 on transfusion compatibility testing. Saline and microcolumn gel methods were used to identify the blood types of the patients. To screen irregular antibodies, salt water, indirect antiglobulin test and polyamine methods were used. Various methods were used to identify antibodies, including saline, indirect antiglobulin test, polyamine and acid diffusion. This paper explores current methods for removing interference caused by monoclonal anti-cluster of differentiation 47. Hu5F9-G4 interferes with reverse typing of ABO blood groups, resulting in agglutination of all reagents used in antibody screening and identification. Patients’ erythrocyte acid dispersive fluid reacted positively with spectrum cells and erythrocytes treated with papain reacted positively with serum. In saline and coagulant amine media, AK117 did not agglutinate with screening cells, but it did with antihuman globulin media. Pre-transfusion testing can be interfered with by anti-cluster of differentiation 47 antibodies. To ensure safe blood transfusions, patients should have their blood type tested and antibodies screened before treatment.

THERMAL CONDUCTIVITY, RHEOLOGY AND ELECTRICAL CONDUCTIVITY OF WATER AND ETHYLENE GLYCOL BASED NANOFLUIDS WITH COPPER AND ALUMINUM PARTICLES

Nanoparticles are mesoobjects that occupy an intermediate position in size between ordinary molecules and macroscopic particles. Suspensions with nanoparticles, called nanofluids, are also specific mesoscopic suspensions. Today it is known that their thermophysical and mechanical properties are not described by classical theories. The unusual properties of these dispersed fluids make them extremely popular in a wide variety of applications. However, successful use of nanofluids involves the prediction of their properties, which in turn requires systematic studies. This paper presents an experimental study on the thermophysical properties of water and ethylene glycol based nanofluids with aluminum and copper particles. The thermal conductivity, rheology and electrical conductivity of nanofluids were systematically studied. The weight concentration of nanoparticles varied from 2.5 to 20%. It was shown that the thermal conductivity of these nanofluids significantly exceeds that of nanofluids with oxide particles. Its higher values are determined by the size of the nanoparticles and the thermal conductivity of the base fluid. The nanofluids studied are either pseudoplastic or viscoplastic. Their rheology is determined by the concentration and size of nanoparticles. The smaller the size of nanoparticles and the higher their concentration, the more likely the change in rheology is. Correlation curves were constructed for the rheological parameters of nanofluids versus the concentration and size of nanoparticles. It was found that the electrical conductivity of nanofluids increases almost linearly with increasing nanoparticle concentration and strongly depends on the nanoparticle size. The electrical conductivity mechanisms of nanofluids were discussed. The speed of sound in a nanofluid and its dependence on particle size were measured.