Concentration Of Solid Particles Research Articles

Potentially hazardous elements in atmospheric precipitation during the warm season (May–September) of 2019 in Moscow

Atmospheric precipitation acts as a significant pathway for pollutants from the atmosphere to the Earth’s surface, and analyzing urban precipitation data on intensity, fallout regime, transfer patterns, and solid particle content helps identify pollution sources. For the first time in the Moscow megacity, the levels of soluble forms of potentially hazardous elements (PHEs) in atmospheric precipitation were studied during the whole summer season of May–September 2019. The concentrations of Al, As, B, Ba, Be, Bi, Cd, Ce, Co, Cu, Fe, La, Li, Mn, Ni, P, Pb, Rb, Sb, Sn, Sr, and Zn were determined using inductively coupled plasma mass spectrometry and atomic emission spectroscopy methods. The research underscores the crucial role of atmospheric precipitation in washing PHEs out of the atmosphere. In May and September, concentrations of PHEs surpass the warm-season average. Notable contamination in May stems from elevated traffic during vacations, extensive burning of plant debris and wood, and pollen transport. Summer months are characterized by reduced forest and agricultural fires, traffic, and increased vegetation, leading to lower PHE concentrations, especially in July, with typical amount of precipitation contributing to pollutant dispersion. Elevated PHE levels in September are observed due to increased traffic load, biomass burning, and the expansion of unvegetated soil areas. Rainwater is enriched with Sb, Pb, Cd, Zn, Cu, B, Bi, P, and Sr, sourced from vehicle emissions, soil particles, industry, construction dust, biomass burning, and forest fires. Moderate enrichment with Ba, Mn, Ni, Co, and Sn also occurs episodically. Regression analysis highlights solid particles’ role as a major PHE source in rainwater, with the longer antecedent dry periods and the higher acidity level of rain intensifying the accumulation of PHEs. Long-range transport plays a lesser role, with Southern and Northern Europe, Western Siberia, and the central part of European Russia contributing meaningfully.

Study on the effect of particles in oilfield produced water on the deposition process of CaCO3

In crude oil production, scale deposition significantly reduces production output and elevates operational costs, posing a severe threat to production safety. While chemical methods have been extensively explored for the scaling and inhibition of inorganic salts, the inorganic scaling triggered by solid particle scaling in complex oilfield water has largely been overlooked. This study involves the introduction of particles into a supersaturated CaCO3 solution, utilizing static scale inhibition and conductivity techniques to examine their influence on the scaling process and crystallization rate. It is evident that solid particles expedite the deposition process of CaCO3. Moreover, the deposition rate of CaCO3 is influenced by factors such as the solid particle content, particle size, and stirring speed. It is noteworthy that the presence of solid particles solely impacts the formation rate of CaCO3 crystals, without altering the total deposition. Specifically, under conditions of 70°C, 250/min stirring speed, and 0.08% SiO2 addition, the deposition rate of CaCO3 is enhanced by 13.5%. The nucleus growth rate constant increases from 11.10 × 10-3min-1 to 14.52 × 10-3min-1 and the crystal growth rate constant increases from 3.02 × 10-3min-1 to 3.36 × 10-3min-1 at most. Observations made through scanning electron microscopy (SEM) and polarized light microscopy reveal that scaling occurs predominantly on the added solid particles in later stages, indicating that solid particles in supersaturated solutions serve as crystal nuclei, inducing the growth of CaCO3 crystals and thus accelerating scaling. This research provides valuable insights for the study of scaling in complex water environments.

Entropy Analysis in Magnetized Blood-Based Hybrid Nanofluid Flow via Parallel Disks

Magnetized hybrid nanofluid combined with ferrite and silver in a blood-based liquid presents their vital role in several aspects such as artificial heart pumping system, drug delivery process, the flow of blood in the artery, etc. This is because the high heat transportation rate of the nanofluid is caused by the inclusion of nanoparticles. The current investigation is based on the characteristic of particle concentration comprised of Fe3O4 and Ag in the base liquid blood that passed in between two infinite parallel disks filled with porous matrix. The electrically conducting fluid associated to maximum of 1.5% of volume concentration from each of the solid particles affects the flow phenomena. However, the impact of thermal radiation vis-à-vis the heat dissipation provides efficient heat transport properties with the inclusion of the effective thermal conductivity assumed from the Hamilton-Crosser model. The proposed conductivity model describes the role of particle shapes on the enhanced thermal properties. Further, numerical treatment is obtained for the transformed designed problem following similarity rules that are used for the conversion of the governing equations into their non-dimensional form. The computation of various flow profiles leads to get the entropy generation due to the irreversibility processes. Along with the fluid velocity and temperature distributions, the study is carried out for the entropy as well as the computation of Bejan number and afterwards the simulation of the shear and heat transportation rate are also depicted graphically. The main finding of the proposed study is that solid particle concentrations have a substantial impact to increasing fluid velocity in magnitude, resulting in a narrower wall thickness at both channel walls. Thermal radiation was shown to be more effective at increasing entropy generation and Bejan value.

Study on liquid-phase sintering and magnetic properties of SLA-printed Mn-Zn ferrite ceramics

To obtain Mn-Zn ferrite magnetic ceramic parts with good densification and magnetic properties, a study was conducted. Mn-Zn ferrite magnetic ceramic parts with a solid particle content of 58 vol% were prepared using stereolithography (SLA). The SLA-cured ceramic blanks were degreased and sintered. The degreasing process for Mn-Zn ferrite parts was optimized using a direct heat degreasing method, resulting in a suitable process for the ferrite magnetic ceramic paste system. The method of liquid phase sintering is proposed for sintering the degreased ferrite parts. The study investigated the impact of the content of accelerant, sintering temperature, and holding time on the density and magnetic properties of Mn-Zn ferrite parts. The optimal parameters were found to be a firing aid content of 3 wt%, a sintering temperature of 900 °C, and a holding time of 90 min. Under these conditions, the parts exhibited a density of 4.43 g/cm3, densification of 91.4 %, saturation magnetization strength of 64 emu/g, and coercivity of 10 Oe. Finally, the sintering control mechanism of SLA-printed ferrite magnetic ceramics was analyzed. The study revealed the grain growth process and magnetization principle of Mn-Zn ferrite during liquid phase sintering. This research provides guidance for the subsequent photocuring printing and degreasing sintering of Mn-Zn ferrite ceramics. Additionally, Mn-Zn ferrite magnetic ceramic parts prepared by the SLA method also hold a wide application prospect in various precision electronic components.

Assessment of the contamination by carbonaceous anthropogenic particulates and polycyclic aromatic hydrocarbons (PAHs) concentration in recreational areas of an estuary heavily industrialized in Northern Spain

The commercial management of coal and its by-products has the potential to negatively impact natural coastal environments. The coal conversion processes and coke production are sources of polycyclic aromatic hydrocarbons (PAHs) emissions that also contribute to the pollution of those aquatic environments. This research assesses the contamination by carbonaceous anthropogenic particles and by polycyclic aromatic hydrocarbons of some recreational sites (Arañón, Peña del Caballo and San Balandrán area) located in the Avilés' estuary, an area in Northern Spain that has been heavily industrialized since the 1950s. The results obtained indicate a low concentration of solid organic anthropogenic particles in the intertidal sediments of the recreational sites in the estuary, probably due to the protective measures set in place at the facilities managing bulk coal and coke, which prevents the dispersion of coal dust (and other materials) as well as the eventual failure into the estuary. The characteristics of 16 priority pollutants PAHs analyzed in two recreational sites of the estuary (San Balandrán area), their distribution by aromatic ring number together with their diagnostic ratios demonstrate a pyrogenic nature with a main source from processes of coal and coke conversion (including combustion) in the facilities around the estuary. Some contribution of PAHs derived from petroleum cannot be ruled out. This contamination by PAHS is constant and sustained over time. The majority of the considered PAHs are well above the Spanish Generic Reference Level, (GRL) established for “protection of ecosystems with aquatic organisms”, and only a few of them are notably above the corresponding Spanish GRL established for “other uses of land”, which should include lands for recreational activities. The analysis of the potential toxicity risk of PAHs for human health and the organisms of the aquatic ecosystem suggests a relatively low toxicity risk to very high toxicity risk in the San Balandrán environment according to the concentration and distribution trend of PAHs identified in this area. This trend is dependent on the coastal dynamics and the protection level of the site, which also affect the distribution of the anthropogenic carbonaceous particulates in the same way.

Hydrodynamic Evaluation of a Filtering Hydrocyclone for Solid Particle/Water Separation.

A conventional hydrocyclones is a versatile equipment with a high processing capacity and low maintenance cost. Currently, several studies aim to alter the typical structure of the conventional hydrocyclone in order to modify its performance and purpose. For this, filtering hydrocyclones have emerged, where a porous membrane replaces the conic or cylindrical wall. During the operation of this equipment, in addition to the traditionally observed streams (feed, underflow, and overflow), there is a liquid stream resulting from the filtration process, commonly referred to as filtrate. This work proposes to numerically investigate the solid particle/liquid water separation process in a filtering hydrocyclone using the commercial software Ansys CFX® 15.0. The proposed mathematical model for the study considers three-dimensional, steady state and turbulent flow, using the Eulerian-Eulerian approach and the Shear Stress Transport (SST) turbulence model. This study presents and analyzes the volume fraction, velocity, and pressure fields, along with flowlines and velocity profiles. The results indicate that the proposed model effectively captures the fluid dynamic behavior within the filtering hydrocyclone, highlighting higher pressures near the porous membrane and a higher concentration of solid particles in the conical region, with water being more concentrated in the cylindrical part of the hydrocyclone. Additionally, the findings show that the volumetric flow rate of the filtrate significantly influences the internal flow dynamics, with conventional hydrocyclones demonstrating higher pressure gradients compared to the proposed filtering hydrocyclone.

Exploring the tendency of Brownian agglomeration in polydispersed systems of solid atmospheric aerosols

Recent extensive research has focused on atmospheric aerosol systems, driven by their far-reaching implications for climate and public health, with a goal to identify optimal air quality management practices. This study employs Langevin dynamics to investigate the impact of size distribution and concentration of submicrometer solid aerosol particles on Brownian agglomeration tendencies within an isothermal, hydrostatically balanced atmosphere. To accomplish this, a Langevin dynamic model is devised, and parameters are carefully determined to ensure numerical integration precision, stability, and efficiency. Using this model, we numerically simulate the average agglomeration nucleus and overall agglomeration rate within the system while considering variations in the standard deviation of size distribution and volume fraction of aerosol particles.

A non-contact solid particle moisture sensor based on near-infrared spectroscopy technology

The detection of moisture content in solid particles has important applications in fields such as biological research, coal mine production, and medicine. This article develops a non-contact solid particle moisture sensor (NcSPMS). NcSPMS uses the multi-light source detection method based on the principle of diffuse reflection absorption to detect the moisture content of solid particles with different particle sizes, distributions and colors. Firstly, the stacked LED light source structure (SLED-LSS) was designed to achieve illumination of LED light source for measurement (M-LED) and the LED light source for reference (R-LED) at the same position and exit angle, eliminating the influence of irregular particle size and distribution on diffuse reflected light intensity. Secondly, the stacked LED array light source structure (SLEDA-LSS) was designed to improve the detection light intensity and enable NcSPMS to detect the moisture content of solid particles of different colors. Thirdly, modulated light technology is used for the transmission of moisture content information. Two modulation frequencies were set to modulate the measurement light source and reference light source, and different intensities of square wave currents were determined to drive the M-LED and R-LED to improve detection accuracy. Fourthly, the FFT-KF data processing method was designed to effectively extract the information of diffuse reflection measurement light intensity. Finally, the function expression of moisture content was obtained through cubic fitting, and the detection of moisture content by NcSPMS was achieved. In order to verify the effectiveness of NcSPMS, the NcSPMS control system was designed. The experimental results show that compared with SLED-LSS, SLEDA-LSS improves measurement accuracy; the different current pairs driving M-LED and R-LED affect the measurement accuracy of NcSPMS; NcSPMS can detect the moisture content of white, yellow, green, red, and black sand particles, with the detection range of 0.10–11.00 %. The relative uncertainty obtained by applying NcSPMS to the detection of nickel ore particles is 4.37 %.

Effect of coal suspension concentration and gas-air medium temperature on liquid droplets collisions

Relevance. Understanding the mechanisms of liquid droplets interaction with each other is important for many industrial and technical applications related to solving a range of problems like slag removal in a high-temperature environment, obtaining components of the desired fraction in the food industry, etc. Aim. Establishment of the main patterns of suspension droplets interaction in a gas-air environment with temperature variation. Methods. Using shadow high-speed video recording, the main patterns of the binary collision of suspensions droplets were determined. The paper introduces the results of experimental studies of the characteristics of collisions of droplets of coal-water suspensions in a gas-air environment with a temperature of 90–120°C. Parameters of the generated droplets: radius 1.0–2.2 mm, velocity 0.5–2.0 m/s. Results and conclusions. The authors have determined the modes of collision of droplets of suspensions (coagulation and separation) and the main characteristics of secondary fragments and constructed the maps of the modes of interaction of drops of suspensions with each other when varying the concentration of solid particles in the suspension, the temperature of the gas-air environment and the time the target drop spent in a gas-air environment with an elevated temperature. The conditions were established for the coagulation of droplets, as well as their intensive secondary grinding to intensify their drying, ignition and combustion in boiler furnaces. It was established that an increase in the temperature of the gas-air environment leads to a significant change in the size and properties of droplets, as well as to the occurrence of oscillatory phenomena in the system. It is substantiated that collision of droplets of suspensions in a gas-air environment with elevated temperature is complex and multi-parametric. Its characteristics depend on a combination of factors (surface tension and liquid viscosity, size and shape of droplets, speed of their movement, density and viscosity of gas-air environment). The authors obtained mathematical expressions to describe the boundaries of the modes of the studied processes and schemes for using the results obtained in order to increase the efficiency of the corresponding technological processes.

Study on quantitative generation technology of bio-fluorescence calibration particles based on inkjet generator

Accurate measurements are critical for timely early warning and effective prevention of epidemics due to the continuing impact of bioaerosols on human health. In recent years, researchers have been focused on developing and calibrating online monitoring instruments. However, there is still a lack of laboratory-generated standard aerosol samples suitable for calibration. Therefore, in this study, we utilized a self-developed Ink Jet Aerosol Generator (H-IJAG) to achieve controllable generation of monodisperse aerosol standard particles. The Aerosol Particle Size Spectrometer (APSS, TOPAS 323) was employed as the particle detector. The diameter of the droplet was calculated by measuring the projected area of the droplet in the same image using Image-J software. Experimental results demonstrated that under standardized inkjet parameters, H-IJAG exhibited good reliability and reproducibility, and generated solid particles within (0.4–15) μm. To better simulate the laser-induced fluorescence emission properties of ambient bioaerosol, tryptophan (Trp) and 7-hydroxycoumarin-4-acetic acid (7-HCA) were selected as solutes of the laboratory-generated aerosol samples, which are known bio-fluorescent materials. According to the law of propagation of uncertainty, the relative uncertainty of the volume equivalent diameter of Trp and 7-HCA solid particles by H-IJAG were 0.42 %, while the relative uncertainty of the particle number concentrations of Trp and 7-HCA solid particles generated by H-IJAG were 1.4 %. This optimized IJAG technique provides a promising solution for the accurate calibration of bioaerosol monitors.

Double diffusive thermogravitational convection in a convex U-shaped porous chamber filled with radiative ternary hybrid nanoliquid

This research deals with the intricate dynamics of double diffusive thermogravitational convection within a convex U-shaped porous chamber and sheds light on the use of a radiative ternary hybrid nanoliquid. In this configuration, the lower flat boundary is assumed to be thermally hot and densely concentrated while the curved lateral boundaries remain cold and dilute. The other boundaries of the enclosure are kept under adiabatic conditions. The governing Navier–Stokes equations along with thermal and species equations are effectively solved by employing a higher order compact technique. The developed in-house program has been rigorously verified against experimental and computational benchmark results. The research meticulously examines the impact of several pivotal parameters, including the Lewis number (1≤Le≤20), buoyancy ratio (0≤N≤10), Darcy number (10−4≤Da≤10−2), Rayleigh number (104≤Ra≤106), volumetric heat source/sink coefficient (−10≤q≤10), radiation parameter (1≤Rd≤5), aspect parameter of the U-shaped chamber (0.2≤AR≤0.6), and solid particles concentration (0.0≤ϕthnp≤0.04) of the ternary hybrid nanofluid. The findings are eloquently portrayed through graphical representations by showcasing streamlines, iso-solutals, isotherms, and the dimensionless Nusselt (Nuavg) and Sherwood (Shavg) parameters. Our investigation demonstrates that the ternary hybrid nanofluid outperforms both hybrid and mono nanofluids in facilitating double diffusion processes. Moreover, optimal heat transfer efficiency is achieved under conditions characterized by an aspect ratio of AR = 0.2, Rayleigh number Ra=106, Darcy number Da=10−2, buoyancy ratio N = 10, Lewis number Le = 1, and solid volume fraction ϕthnp=0.04.

Обоснование криогенной технологии осветления сапонитсодержащей оборотной воды хвостохранилища обогатительной фабрики № 1 АО «Севералмаз»

Experience in the operation of the tailings pond of the processing plant No. 1 of Severalmaz JSC has established the impossibility of achieving the conditions for natural (gravitational) sedimentation of solid particles and the necessary effect of clarification of recycled saponite-containing water, the content of solid particles in which currently exceeds 300 g/l (at a rate of 10 g/l). IPKON RAS has developed and tested cryogenic methods for clarification of saponite-containing circulating water from the Plant No. 1 of Severalmaz JSC. The experimental substantiation of the technological effectiveness of cryogenic methods for clarification of saponite-containing circulating water was carried out in three stages: 1) laboratory experiments, the results of which substantiate the cryogenic method as the most effective for the sedimentation of saponite particles in samples of circulating water of a tailings pond; 2) pilot testing with assessment of the technological efficiency of the process of freezing saponite-containing circulating water using two variants of cryogenic technology in the conditions of an existing tailings pond; 3) semi-industrial testing with assessment of the technological efficiency of the process of thawing frozen saponite-containing circulating water and the stability of the saponite-containing sediment formed during their clarification of circulating water. The results of pilot industrial tests established the technological efficiency of two options for implementing cryogenic technology for clarification of saponite-containing recycled water using the method of freezing and subsequent thawing due to the established possibility of obtaining a layer of clarified water with a depth of 0.5 to 1 m with a solid content of less than 1 g/l: – with the use of thermal stabilizers due to the possibility of obtaining an ice mass with a thickness of up to 2.5 m and a volume of up to 213 m3 (37 % of the original volume); – using the layer by-layer freezing method due to the possibility of obtaining an ice mass with a thickness of up to 2 m. Based on the results obtained, cryogenic technology for clarification of saponite-containing recycled water using developed options for using methods of its sequential freezing and thawing is recommended for industrial testing for a preliminary assessment of technical and economic indicators in the natural conditions of the tailings pond No. 1 of Severalmaz JSC.

Nano-hydroxyapatite Pickering emulsions as edible mayonnaise-like food sauce templates: A novel approach for food design

Pickering emulsions have the potential to enhance product stability and provide opportunities to create functional solutions that align with labelling requirements. The present work aims to develop Pickering emulsions stabilised by nano-hydroxyapatite (n-HAp) particles to replace traditional mayonnaises. The study addresses the effect of n-HAp solid particle concentration (5–15 wt%) and oil-water ratio (50:50, 60:40, 70:30, and 80:20, v/v) on emulsion stability, rheological properties, and oxidative stability. The results indicate that the produced Pickering emulsions have good stability for the tested period of 90 days, except for the 80:20 o/w emulsion that undergone a prompt quick phase separation. The Pickering emulsions produced with higher n-HAp concentration or oil content have a semi-solid structure, rendering them desirable options for replicating the texture of traditional mayonnaises. Regarding oxidative stability, the Pickering emulsions showed considerably improved stability compared to commercial mayonnaises (∼13 times higher), suggesting higher resistance to peroxidation and a longer shelf-life.

Numerical simulation study on erosion characteristics of desulfurization slurry using shell-and-tube heat exchanger for low-grade waste heat utilization

The wet desulfurization yields slurry with a moderate temperature and stable supply and thus holds promise for waste heat utilization. However, the corrosive nature and solid particle content of desulfurization slurry from the wet desulfurization process pose potential erosion challenges in waste heat utilization heat exchangers, which is an aspect scarcely explored in the existing literature. The present study aimed to investigate the erosion characteristics in desulfurization slurry heat exchangers using numerical simulation approaches, which can offer crucial insights for practical application in low-grade energy recovery. The result identified slurry mass flow rate and composition as essential factors of erosion distribution. Higher mass flow rates enhance heat transfer efficiency. Still, paradoxically, lower flow rates lead to more pronounced erosion, with a slurry mass flow rate of 35 kg/s resulting in nearly double the erosion compared to the benchmark condition of 56 kg/s. This phenomenon is ascribed to lower fluid velocities in the heat tubes, where the influence of changed velocity diminishes, but slurry exhibits more stable flow at higher mass flow rates. Furthermore, it is also observed that both elevated solids content and particle size lead to an increase in erosion rates. The difference in erosion caused by solid particles with particle sizes in the range of 200–350 µm is marginal. The heat exchanger structure and arrangement also impact fluid flow and erosion. While the difference in fluid flow between vertically and horizontally arranged heat exchangers is negligible, the erosion was significantly reduced to 1/10 in the vertical arrangement. The no-tube-in-window heat exchangers, designed to minimize vibration, exhibit reduced heat transfer capacity alongside diminished and more uniform erosion. The augmentation of tube passes reduces overall erosion but focalizes severe erosion at the slurry inlet, which presents a potential design solution.

Research of the Wear Rate of Elements of the Flow Part of Centrifugal and Axial Pumping Units

The paper presents the results of a theoretical and experimental study of the wear rate of the elements of the flow part of centrifugal and axial pumps. Theoretical formulas recommended by various authors, obtained for models with flat samples based on energy theory, do not take into account the features of hydraulic machines. Considering the movement of solid particles in the inter-blade channels of the impellers of centrifugal and axial pumps, calculation schemes were chosen that correspond to the hydraulic and physical wear processes. The analysis shows that the influence of centrifugal and inertial forces in the inter-blade channel of the impellers of centrifugal and axial pumps causes separation and redistribution of solid particles in the flow. As a result, in centrifugal pumps in the end part of the blade and axial pumps in the end gap of the impeller, the local concentration of solid particles increases compared to the average. The work also provides dependencies for calculating the intensity of water-abrasive wear of pump working parts.

MHD peristaltic two-phase Williamson fluid flow, heat and mass transfer through a ureteral tube with microliths: Electromagnetic therapy simulation

The ureter typically experiences a frequency of one to five peristaltic contractions per minute. However, it is important to note that these contractions can be disrupted by various physical and mechanical irritants. Ionic contents in the urine make it electrically conducting and responsive to electromagnetic body forces. MHD can be deployed in bio magnetic therapy to control or mitigate symptoms associated with peristaltic pumping in the urinary system. This article therefore focuses on the hydromagnetic effects on flow patterns of urine with debris (monoliths). The mechanism of urine flow is largely coordinated by the kidneys. The flow inside the ureter is interrupted by microliths, which are generated by the sedimentation of excretory products. To simulate this, a two-phase formulation is adopted, comprising the electromagnetic urological viscous fluid phase and the particulate phase for solid grains. The peristaltic propulsion of two-phase liquid in the ureter is simulated as a sinusoidal wave propagation of incompressible non-Newtonian fluid. The Williamson viscoelastic model is deployed for the rheology. Heat transfer is also included with Soret thermo-diffusion and viscous heating effects. Long wave and low Reynolds number approximations are employed based on lubrication theory. The mass, momentum, energy and concentration conservation equations with associated boundary conditions are rendered non-dimensional via appropriate scaling transformations. A numerical solution is achieved via BVP4C MATLAB quadrature. Graphical visualizations of the velocity, temperature and concentration (solid grains) are given for the influence of suspension parameter ( ζ ), Hartmann number (M), Prandtl number (Pr), Weissenburg number (We), particle volume fraction (C), Eckert number (Ec), Soret number (Sr), Schmidt number (Sc). The novelty of the present work is therefore the simultaneous consideration of a generalized two-phase model, wall slip, non-Newtonian characteristics, cross diffusion, viscous dissipation, mass diffusion, magnetic body force and curvature effects in peristaltic urological transport, which has not been undertaken previously. The detailed simulations reveal that the flow velocity is reduced due to the presence of solid particles and the channel curvature, in comparison to the flow in an unobstructed channel devoid of solid particles. Enhancing the hydrodynamic slip parameter speeds up the movement of particles and fluid near the channel walls, boosts wall skin friction, raises pressure difference in the pumping area, and amplifies bolus magnitudes.The rise in peristaltic pumping results in a reduction in solid particle concentration, which is significant phenomena.This theoretical approach may aid in treating conditions such as Urinary Tract Infections (UTIs). The computations effectively demonstrate that significant manipulation of urological pumping characteristics can be achieved with an electromagnetic field. Some new features of two-phase ureteral dynamics are highlighted as relevant to magnetic therapy techniques, which may be beneficial to clinicians.

Numerical simulation and experimental study of hole cleaning

Insufficient hole cleaning causes tool wear and reduces drilling efficiency. Existing evaluation methods and models are limited. In this study, a universal method is proposed to assess hole cleaning efficiency (HCE). A coupled computational fluid dynamics and discrete element method (CFD-DEM) numerical model for non-Newtonian fluid simulation of cuttings transport is developed. The influence of various factors on HCE was analyzed from an energy and particle collision perspective, with a particular focus on the mechanisms of fluid viscosity and rate of penetration (ROP) on cuttings settling. Results show that increased fluid viscosity improves HCE, while excessive viscosity negatively affects it. Higher ROP results in increased solid particle concentration and collision probability, leading to energy loss and reduced efficiency. Lower HCE was observed when the inclination deviated from the vertical. The HCE can be significantly improved by increasing the fluid velocity and reducing the eccentricity. A comprehensive prediction model for HCE is established using Design of Experiment (DOE), dimensional analysis, and nonlinear regression. This model incorporates a generalized fluid apparent viscosity, taking into account the impact of each rheological parameter. Additionally, it can be applied to predict hole cleanliness in both Newtonian and non-Newtonian fluids. By comparing the experimental results of hole cleanliness in three distinct fluids, the regression model yielded reliable predictive results. The findings enhance understanding regarding how fluid properties and the ROP affect cuttings transport and enable precise and convenient prediction and optimization of hole cleaning efficiency.

Thermal and mass exchange in a multiphase peristaltic flow with electric-debye-layer effects and chemical reactions using machine learning

The present investigation delves into the analysis of mass and thermal transmission during the peristalsis of a two phase flow of a Prandtl fluid, within a symmetric channel by considering entropy generation and minimization. The considered flow is examined by taking into account the impacts of electroosmotic effects through Electric Debye Layer (EDL) and chemical reactions followed by the lubrication theory approximation. Numerical solutions are acquired for the consequential differential equations through artificial neural networks (ANN) based fitness functions. The artificial neural networks (ANN) based fitness function optimized through hybrid evolutionary algorithms especially ABC (artificial bee colony) and NNA (neural network algorithm) like ANN-ABC-NNA. For the efficiency and validation of the algorithm we conduct the one hundred (100) independent runs. The obtained results through ANN-ABC-NNA are compared with the exact solutions for validation of results. In the present examination, the velocity profile is noticed to increase by the rise in the electroosmotic factor and solid particles concentration, while it decreases for the Prandtl fluid parameter. This research holds practical significance in diverse applications, particularly in the design and optimization of microfluidic devices.

Influence of mechanical impurities composition on formation of organic deposits

Relevance. The need to study the effect of solid particles in the oil stream on formation, composition and structure of deposits. Modern models of formation of asphalt-resin-paraffin deposits, based on correlation dependencies or empirical data, do not take into account the influence of the content of solid particles in oil to the proper extent. Recent studies show that various solid particles in oil can affect both the critical velocity and the structure of the formed deposits, but the effect of various particles on the intensity of formation of asphalt-resin-paraffin deposits remains unexplored. Aim. To study the effect of various sand fractions on the intensity of formation, composition and structure of asphalt-resin-paraffin deposits Methods. Modeling of formation of asphalt-resin-paraffin deposits at the laboratory installation “Cold Finger” when adding various sand fractions to oil; studying composition and structure of deposits after the conducted investigations using a microscope. Results. According to the research results, there is a significant increase in the intensity of formation of asphalt-resin-paraffin deposits when large fractions of sand are added to oil at a concentration of 5% or higher. It is worth noting that small fractions have almost no effect on the amount of deposits formed. Also, if various fractions are added to oil in equal proportions, there is almost no effect on the intensity of formation of asphalt-resin-paraffin deposits. When analyzing the deposits images from a microscope, it can be concluded that paraffin molecules, when interacting with sand particles of a dimension greater than 0.05 mm, form homols, and with an increase in the fraction, their structural strength grows. Conclusions. The study of modern models of formation of asphalt-resin-paraffin deposits and current articles made it possible to understand that the issue of studying the factors of formation of asphalt-resin-paraffin deposits, in particular the effect of the presence of solid particles in oil, remains open. The results of this article can be aimed at improving existing technologies in the field of modeling paraffin formation, as well as contribute to the further work of researchers in this direction.

Implementasi Sistem IoT Pada Akuakultur Dan Hydroponik (Akuaponik) Modern Untuk Pertumbuhan Ikan Nila

In modern times, there are many types of agricultural and fish farming systems, one of which is the modern aquaculture system which has been recognized as an innovative method of sustainable food production that combines fish cultivation with agriculture simultaneously. Modern aquaponics is able to overcome problems in urban areas which require land for growing crops and cultivating fish. Good fish cultivation means always monitoring the growth and health of fish to reduce the risk of crop failure, therefore this research aims to implement an Internet of Things (IoT) system in modern aquaponics to increase the growth of tilapia. IoT parameters consisting of pH sensors, Total Dissolved Solids (TDS) sensors, and temperature sensors are used to monitor water quality conditions in modern aquaponics. Through IoT systems, data collected in real-time enables more effective environmental monitoring. The creation of an IoT system in modern aquaponics shows that the implementation of IoT can increase the efficiency of modern aquaponic environmental management, resulting in better fish growth and plant productivity. This was verified through the pH sensor test results with a value of 7.2 indicating optimal conditions of acid-base balance in the water, which is essential for the health of tilapia fish. The TDS sensor test with a value of 300 ppm confirmed that the concentration of solid particles in the water was at an optimal level, which is also an indicator of the health of the tilapia fish. Temperature measurement using a temperature sensor with a value of 28°C, shows that the water temperature is within the ideal range for comfort for tilapia, which is usually comfortable at temperatures between 28-30°C