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This paper explores the combined influence of an axial electric field and a perpendicular magnetic field imposed on rotating micro-parallel plates immersed in an electrolyte solution. A specialized computer program was developed to solve the velocity as well as the EDL potential fields using the finite difference method, employing the Debye-Hückel (DH) approximation to linearization the EDL potential. The study examines the influence of various non-dimensional parameters, including rotational speed (ω), Hartmann number (Ha), Debye-Hückel parameter (κ), and the non-dimensional parameter ' S', on axial, and transverse velocities, wall shear stress, and net flow rate. Results demonstrate that, both velocity components decrease with increased rotational speed and Hartmann number, while the net flow rate increases with the Debye-Hückel parameter for both rotating and non-rotating systems. The impact of these parameters on shear stress was also analyzed. Analysis of Ekmann spirals in the velocity plane revealed closed spirals at a higher rotational speed and open spirals at lower speeds, with spiral size reducing as rotational speed increases. [ABSTRACT FROM AUTHOR]

AbstractA precisely controlled solution-phase approach was employed to synthesize copper nanofluid through the reduction of copper sulfate by fructose in the presence of cetyltrimethylammonium bromide, utilizing a mixture of water and ethylene glycol in 1:1 ratio as the base fluid. We delved into the nanofluid’s thermal conductivity and rheological properties, with a keen interest on particle size and reaction rates that exhibited significant sensitivity to variations in reaction parameters. The homogeneous dispersion of nanoparticles in the base fluid resulted in an augmentation of thermal conductivity to 2.31 Wm−1K−1 for particle loading fraction of 0.19%, with a never before achieved stability of 9 months. This method has proven to be not only straightforward and dependable but also efficient for the rapid synthesis of highly stable Newtonian nanofluids, underscoring the nanofluid’s potential for highly powerful cooling applications. [ABSTRACT FROM AUTHOR]

The investigation of entropic variations in the thermal transport mechanism produced by buoyantly driven temperature gradients has attracted significant attention because of excellent physical significance. Therefore, the prime consent to manipulate the current investigation is to explore the impact of change in the aspect ratio of the trapezoidal cavity in the optimization of the entropy phenomenon. After attaining motivation from its practical essence different entropies including thermal, viscous, and local are estimated. Additionally, global quantities such as average Bejan and Nusselt numbers calculated along with total entropy are measured against flow concerning parameters (aspect ratio (AR), Rayleigh number (Ra) and irreversibility ratio (ϕ )). Numerical experiments are performed by implementing a finite element approach using open-source software renowned as COMSOL Multiphysics. Before the accomplishment of the outcomes, confirmation of the numerical technique is assured by establishing grid sensitivity testing. Comparison of results between present and previous studies is also demonstrated. A wide range of involved sundry parameters varying from 10 - 4 ≤ ϕ ≤ 10 - 2 , 10 2 ≤ Ra ≤ 10 5 and 0.25 ≤ AR ≤ 0.75 are accounted. It is concluded that by escalating the aspect ratio from 0.50 to 0.75, the magnitude of the local entropy enhances from 3370 to 3424. It is revealed that the highest value of viscous entropy that is, 45, is achieved at Ra = 105 and by keeping the aspect ratio of enclosure equal to 0.75, whereas, the thermal entropy approaches 2 for the same situation of parameters. The magnitude of the average Bejan number reaches unity at AR = 0.5 and Ra = 105, whereas for low and high aspect ratios it depicts a magnitude less than 1 for the same Rayleigh number. [ABSTRACT FROM AUTHOR]

The heat transfer analysis and time dependent magneto hydrodynamics boundary layer flow of three dimensional viscous incompressible Newtonian fluid in rotating frame across the extending surface subject to microgravity g∗(t)(=go[1+ϵcos(πωt)]k) is investigated. The gravity modulation and gradient of fluid temperature typically generate buoyant convective flows in case of various situation, most likely in environment of low gravity or microgravity, the systems can operate under purely diffusive conditions in this environment since buoyancy-driven fluid flows and sedimentations are significantly diminished. Recent years have seen a growing interest of researchers in mixed convection that is regulated by microgravity environment due to highly extensive modern technological applications. The innovative aspect of the current study is the consideration of the impacts of gravity jitters (g-jitter) in rotating Newtonian fluid. The leading governing equations of elaborated fluid flow problem transformed into form of non dimensional coupled non-linear PDEs (partial differential equations) by the help of appropriate similarity functions. For seek of numerical solution, a very powerful technique, finite element method is used via MATLAB. The flexibility, robustness, and exactness of this technique make it a strong tool for solving fluid flow problems. The magnitude of average Nusselt number exhibits 16% & 17% decline against 46.31% increment in Coriolis and magnetic forces. Rising the amplitude of modulation results in proportional rise and decline in skin friction and heat transfer. By increasing strength of rotating parameter, magnetic parameter and frequency modulation parameter, the velocity profile declined while, temperature field has opposite trend against these parameters. The comparison of current results with existing results is given and found a very good agreement between them.

Several different industries and disciplines can benefit from heat transfer in peristaltic flow in curved ducts, including biomedical engineering, industrial processes, microfluidics etc. In this study, the thermal aspects of peristaltic flow are thoroughly examined, with a particular focus on the impact of entropy generation in a symmetric curved duct. Notably, the curvature of the duct introduces additional complexity, enhancing the significance of this research. The resulting system of equations is then analytically solved using homotopy perturbation method (HPM). It is observed that fluid’s temperature is increasing directly with aspect ratio but amplitude ratio and curvature exhibit inverse impact on it. It is also evaluated that the fluid’s peristaltic pressure is enhanced by large curvature. The obtained results offer valuable guidance for designing and optimizing peristaltic systems in a wide range of applications, including biomedical devices, industrial processes, and microfluidic systems. [ABSTRACT FROM AUTHOR]

In order to investigate the diffusion mechanism of slurry in post-pile grouting, this study develops a formula for calculating the diameter and the climb height of the cement core of jet grouting (CCJG). This research conducts field orthogonal tests using a self-developed grouting nozzle to analyze the effects of disturbance pressure (DP), disturbance time (DT), grouting pressure (GP), and the water–cement ratio (W/C) on the dimensions and strength of the CCJG. The findings revealed that the theoretical formula for calculating the diameter of the CCJG deviates by approximately 8% from the field test results, confirming the formula's validity. In addition, the DP and DT significantly influence the volume of the CCJG, displaying a linear increase with their augmentation. Conversely, the W/C and DP predominantly affect the CCJG's strength. Notably, an increase in the W/C results in diminished strength, whereas an increase in the DP enhances it. In addition, soil reinforcement is achieved through replacement, mixing, and compaction as the grout flows outward from the center of the grouting hole. These insights offer a theoretical foundation and technical support for effective grouting construction practices. [ABSTRACT FROM AUTHOR]

Nanofluids are used in heat exchangers, radiators, and other cooling system to improve its efficiency and enhance the thermal conductivity. Therefore, this study is carried out to inspect the influence of bioconvected Williamson fluid flow in the manifestation of nanoparticles. Furthermore, the impact of activation energy and magnetic field is part of this study. For motivation of problem, the effects of velocity and thermal slips are taken into account. Similarity approximation is used to transform the set of PDEs of governing equations of current flow model into a couple of nonlinear ODEs. The resulting set of equations of Williamson Buongiorno's model is numerically solved with help of MATLAB using bvp4c built-in solver. The inspiration of evolving parameters like Lewis number, thermophoresis, Schmidt number, Brownian motion, Prandtl number, Bioconvected Peclet number, and slips parameters on velocity, temperature, concentration, and density field is graphically analyzed. The notable thing is that a very good comparison for both Williamson and Newtonian fluids is obtained for various parameters. In addition, the effect of physical quantities is computed in the form of tables. This research offers a comprehensive exploration of the interrelated domains of Williamson fluids, Newtonian fluids, MHD effects, activation energy, bioconvection, and dual slip effects. The improvement in the values of the activation energy E is enriched in concentration field. Thermal boundary layer increased with thermal slip; opposite behavior is noted for velocity slip. Furthermore, investigation shows a 25% augmented transport efficiency in non-Newtonian fluids, further boosted by 15% with microorganisms and nanoparticles. These findings presented herein contribute to a deeper understanding of these phenomena and pave the way for further advancements in diverse fields, from fluid mechanics to bioengineering. [ABSTRACT FROM AUTHOR]

Abstract\nHIGHLIGHTSA Newtonian nanofluid containing suspended nanoparticles can substantially improve heat transfer due to enhanced energy transport mechanisms. This theoretical study investigates heat and mass transfer in biological tissues using such a nanofluid under a magnetic field. These properties have promising medical and engineering applications. The nonlinear governing equations were transformed into ordinary differential equations using similarity variables and numerically solved with MATLAB boundary value problem solver bvp4c, subject to appropriate boundary conditions. Results demonstrated increasing the heat source parameter dramatically raised tumor interstitial temperature. This heating, along with improved nanoparticle accumulation within the tumor due to the thermal effects, are together essential for effective hyperthermia treatment. The model provides new insights into tuning heat and mass transport mechanisms in biological tissues via nanofluids for therapeutic applications. Therefore, the findings of this study may improve the efficacy of thermal therapy in treating cancer.This work examined magnetic field effects on heat transfer and nanoparticle (NP) transport in a Newtonian nanofluid within tissue surrounding a blood vessel.Elevating the external heat source power distributes NPs and increases tumor temperature.Boosting the thermophoresis coefficient enhances NP dispersion into tissue.Tuning heat and mass transport mechanisms via nanofluids shows promise for advancing hyperthermia cancer treatment.This work examined magnetic field effects on heat transfer and nanoparticle (NP) transport in a Newtonian nanofluid within tissue surrounding a blood vessel.Elevating the external heat source power distributes NPs and increases tumor temperature.Boosting the thermophoresis coefficient enhances NP dispersion into tissue.Tuning heat and mass transport mechanisms via nanofluids shows promise for advancing hyperthermia cancer treatment. [ABSTRACT FROM AUTHOR]

The Newtonian fluid flowing across a semi-infinite plate with variable velocity and pressure is considered in this work. The dimensionless governing equation is obtained by introducing the dimensionless quantities. For infinite region, the artificial boundary approach by using the Laplace transform is applied to gain the absorbing boundary condition (ABC) in a finite region which we call the inner region. The approach differs from the traditional approximation method for infinite boundaries with large values and is first applied to the research. And the stability of the ABC is verified by considering the same point of the outer region and inner region. The numerical difference scheme by using the L1-scheme to approximate the fractional derivative is used to get solutions, and the feasibility assessments, such as stability and convergence, are developed. Three numerical examples are given. In the first example, the exact solution is gained by importing a source term. Through the comparison of numerical solution with exact solution verifies the accuracy of difference method. A comparison between the velocity distribution of the ABC and the infinite boundary approximated by a large value is also discussed and graphically analyzed. In the following two examples, by analyzing the fluid flow over the plate with assorted speeds or pressure gradient, the impact of correlative parameters on the velocity distribution and the flow mechanism are thoroughly analyzed. [ABSTRACT FROM AUTHOR]

This study envisions the hydrothermal characteristics of a viscous fluid in a homogenously permeable hexagonal enclosure. Permeability aspects in the flow domain are described by employing the Brinkman-extended Darcy law. A corrugated hexagonal enclosure along with the placement of a star-shaped fin is taken into account. Heated rectangular blocks at horizontal extremities are installed and sliding sides of the enclosure are considered to be cold to provide convegtive potential to the flow. In addition, adjoining portions of the heated rectangular blocks are supposed to be adiabatic. The dimensionless governing .quations of the resultant problem are derived initially and then solved numerically by implementing the Galerkin finite element approach, and COMSOL is obliged. For this purpose, first, domain discretization is demonstrated in view of 2D elements by performing hybridized meshing. Then, the system of non-linear equations is resolved by a non-linear solver (PARADISO). The grid convergence test is performed to confirm the credibility of the carried out simulations by calculating the average Nusselt number at different refinement levels. A change in associated distributions against the involved physical parameters (Darcy number (Da), Rayleigh number (Ra), and Prandtl number (Pr)) for a wide range is revealed through graphs and tables. Quantities like kinetic energy and heat flux (local and average) are also evaluated through concerned parameters. The results clearly demonstrate that the Darcy number tends to reduce the heat transfer rate. In particular, it is depicted that by increasing the Rayleigh number (Ra), strengthening in the temperature potential arises in the system, thereby magnifying the heat transfer rate. Moreover, it is disclosed that by reducing the Darcy number, kinetic energy shows a decreasing trend. [ABSTRACT FROM AUTHOR]

Bubble formation in a square microchannel having a converging shape merging junction has been studied using the Coupled Level-Set and Volume-of-Fluid (CLSVOF) method. The influence of variations in merging junction angles, fluid properties, and operating conditions on the bubble length and pressure drop has been analyzed. The results show a direct relationship between surface tension, gas-liquid flow ratio, and the inverse relation of continuous phase viscosity with the bubble length. Moreover, opposite variations of these parameters are observed for pressure drop. This work reveals a discerning influence of the angle variations of merging junction on the interplay between inertial, viscous, and surface tension forces in the bubble formation mechanism. We envisage that this numerical work will be of significant interest for the process intensification in various industries that deal with gas-liquid microfluidic systems. [ABSTRACT FROM AUTHOR]

This study aims to enhance the comprehension of the fundamental fluid behavior by comparing Newtonian fluid with second-grade fluid under the influence of periodic magnetic fields, nonlinear radiative nanomaterial, and a porous stretched surface featuring a heat source. The governing equations' dimensionless forms are generated by applying the proper transformations, and the explicit finite difference (EFD) method is used to solve the numerically-derived solution while carefully maintaining stability and convergence standards. The results include velocity, heat, and mass transfer oscillation profiles; streamlines, and isothermal lines. Nusselt and Sherwood numbers are correlated with different factors according to tabular studies, and data prediction and regression are done using graphical representations. This study revealed that, in contrast to Newtonian fluid, second-grade fluid flow elevates velocity profiles with variations in chemical reaction parameters and mass Grashof numbers. Conversely, the thermal non-linear radiation and heat source in second-grade fluid particles effectively enhance the temperature field, although the temperature increase is more pronounced in Newtonian fluid compared to second-grade fluid. Also, second-grade fluid flow exhibits a lower mass transmission rate but higher stress sharing and heat transmission rates compared to Newtonian fluid flow. The implications of this research may impact prostate cancer treatment, as cancer patients have already benefited from the use of magnetic fields to regulate drug release from nanoparticles. Although the greater stress sharing and heat transmission rates may be used for targeted therapy, the lower mass transmission rate raises the possibility of benefits in controlled release scenarios.

Abstract Current communication deals with the flow impact of blood inside cosine shape stenotic artery. The under consideration blood flow is treated as Newtonian fluid and flow is assumed to be two dimensional. The governing equation are modelled and solved by adopting similarity transformation under the stenosis assumptions. The important quantities like Prandtl number, flow parameter, blood flow rate and skin friction are attained to analyze the blood flow phenomena in stenosis. The variations of different parameters have been shown graphically. It is of interest to note that velocity increases due to change in flow parameter gamma and temperature of blood decreases by increasing nanoparticles volume fraction and Prandtl number. In the area of medicine, the most interesting nanotechnology approach is the nanoparticles applications in chemotherapy. This study provides further motivation to include more convincing consequences in the present model to represent the blood rheology.

The current problem is significant because it concerns the modeling of electroosmosis regulated peristaltic flow of hybrid Newtonian liquid as seen within a symmetric tube. This model provides an exciting mathematical formulation with unexpected features, especially when impacted by electroosmotic forces, which aids in understanding how these complex fluids behave under different conditions. It is essential for maintaining product integrity, which can help us avoid problems in the future. The manuscript focuses on the perception of copper and SIO2 hybrid nanoparticles using blood as a means of transport fluid. The theoretical formulation is based on nanoparticles having blades, platelets, and cylindrical forms. At the microscale, physiological transport phenomena generated by pressure to form a pressure gradient, velocity, and thermal slip may be used to articulately construct a theoretical treatment for rheumatoid arthritis and biomimetic thermal pumping systems. The boundary conditions for computation are generated using the proper transformations, and Euler's technique is used to produce an accurate solution of the resulting system of nonlinear ODEs raised by governing PDEs. "Mathematica" computer software applications are associated to the various physical aspects that impact flow and pumping. A comprehensive parametric study found that employing blood-infused nanoparticle blades to treat autoimmune disorders produced positive results. Trapping, a basic peristaltic pumping phenomenon, is also depicted and quickly discussed. This research could have uses in microfluidic devices, medication delivery systems, and other industries where precise fluid flow control is required. Researchers may be able to improve the efficiency and accuracy of such systems by regulating fluid flow using an electric field. [ABSTRACT FROM AUTHOR]

Current communication deals with the flow impact of blood inside cosine shape stenotic artery. The under consideration blood flow is treated as Newtonian fluid and flow is assumed to be two dimensional. The governing equation are modelled and solved by adopting similarity transformation under the stenosis assumptions. The important quantities like Prandtl number, flow parameter, blood flow rate and skin friction are attained to analyze the blood flow phenomena in stenosis. The variations of different parameters have been shown graphically. It is of interest to note that velocity increases due to change in flow parameter gamma and temperature of blood decreases by increasing nanoparticles volume fraction and Prandtl number. In the area of medicine, the most interesting nanotechnology approach is the nanoparticles applications in chemotherapy. This study provides further motivation to include more convincing consequences in the present model to represent the blood rheology. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the impact of catheterization on swallowing if esophagus suffers from a hiatus hernia. It is modeled as a partially diverging tube having a peripheral layer of different viscosity besides the core layer. The model duly considers mass conservation in the two layers separately. It is inferred that even in the presence of a catheter inside esophagus, any sliding herniation requires less pressure for flow, i.e., swallowing will be easier if the esophagus diverges more near the cardiac sphincter. However, the presence of a catheter requires esophagus to work more in order to swallow the same quantity. Pressure enhances by many folds, but its distribution remains similar. The time-averaged flow rate and the maximum pressure, restraining fluid from swallowing, give some clues about a catheterized herniated esophagus. The flow enhances for a thinner peripheral layer. A more viscous peripheral layer as well favors flow. However, the thickness of the catheter hinders swallowing. This is to be taken care of while a patient undergoes any catheterized treatment. Increasing wave amplitude and dilating parameters can enhance flow in the presence of a catheter. It is also concluded that the frictional forces exerted by the tube wall on the peripheral layer increase in the catheter's presence. [ABSTRACT FROM AUTHOR]

This study investigates the dynamic flow of a Newtonian fluid through two coaxial cylinders, each rotating at speeds Ω 1 (t) (inner cylinder) and Ω 2 (t) (outer cylinder). We derive equations of motion for disturbances in balance, yielding a controlled system characterized by parameters such as Taylor number, wave number, frequency ratio, and interior cylinder frequency. We introduce numerical techniques for solving this system, employing spectral Chebychev collocation for spatial resolution and a combined approach of Floquet theory and Runge–Kutta method for temporal resolution. Our refined approach enables comprehensive analysis of fluid dynamics within the rotating coaxial cylinders, showcasing the interplay of various control parameters. [ABSTRACT FROM AUTHOR]

Nano and dusty fluids provide new possibilities to improve energy transfer efficiencies. Motivated by immiscible fluids duct flow framework in the filtration of hydrocarbon materials, the objective of this manuscript is to present the numerical study of three immiscible fluids namely, copper oxide-ethylene glycol (CuO-EG) water nano, Saffman dusty, and plain Newtonian fluids in the horizontal channel. For the formulation of the mathematical model, the dusty fluid is positioned between the immiscible layers of the nanofluid and Newtonian fluid. The interface between the immiscible fluids is continuous and non-deformable in nature. The flow is driven by an externally time-dependent pressure gradient. The novel radial basis function pseudospectral (RBFPS) method is employed to solve the governed partial differential equations, and the resulting outcomes are compared with cubic B-spline differential quadrature and finite difference method. The impact of several crucial fluid parameters, comprising the volume percentage of CuO nanoparticles, the dust particle concentration parameter, and various others on velocity profiles, are presented graphically. It is observed that despite being present only in the lower zone, the CuO nanoparticles have an impact on the flow velocities in other zones also. The fluid and particle velocities decrease as the volume fraction of CuO increases. [ABSTRACT FROM AUTHOR]

Efficient transport in vertical pipeline hydraulic lifting systems is vital for coarse-grained ore, necessitating a deep comprehension of the settling traits of coarse mineral particles. In this study, we conducted a series of settling experiments on individual coarse particles in Newtonian fluids with varying viscosities, employing a self-designed and manufactured settling apparatus. A total of 133 sets of experimental data on the free settling of coarse particles in Newtonian fluids were obtained by recording the particle settling process with a high-speed camera and applying image processing techniques. A mechanical model was employed to perform statistical analysis on the experimental data and establish a predictive model for the drag coefficient and an explicit predictive model for the settling terminal velocity of coarse-grained ore in Newtonian fluids. The average relative errors between the predicted values and experimental values of the drag coefficient and settling terminal velocity models are 4.26% and 7.34%, respectively. This confirms the reliability of the provided predicted model, providing a theoretical foundation for determining the hydraulic lifting speed of coarse mineral particles in vertical pipelines for deep mining. [ABSTRACT FROM AUTHOR]

In petroleum engineering, accurately predicting particle settling velocity during various stages of a well's life cycle is vital. This study focuses on settling velocities of both spherical and non-spherical particles in Newtonian and non-Newtonian fluids. Utilizing a dataset of 931 experimental observations, an artificial neural network (ANN) model with a 7-42-1 architecture is developed (one input layer, one hidden layer with 42 neurons, and one output layer). This model effectively incorporates particle settling orientation and the inclusion of the settling area ratio, enhancing its predictive accuracy. Achieving an average absolute relative error (AARE) of 8.51%, the ANN model surpasses traditional empirical correlations for settling velocities in both Newtonian and power-law fluids. Key influencing factors, such as the consistency index and particle equivalent diameter, were identified. This approach in ANN model construction and data analysis represents a significant advancement in understanding particle dynamics. [ABSTRACT FROM AUTHOR]

Investigation on the simulation effects of free convection flow from a cold and heated cone with a downward pointing tip in various stagnant fluids is presented in this study. Examining the steady-state isotherm patterns around the cone to determine heat transfer characteristics. Results are presented for friction factor and Nusselt number distributions Over the surface of the cone for distinct dimensionless quantities like Pr and Gr to deliver an extensive class of dimensionless numbers. The commercial program ANSYS CFX 16.0 was used to solve the regulating equations which governs the motion vis., momentum mass and energy were computed. The temperature as well as flow fields are coupled using the Boussinesq approximation in order to simplify the governing equations and capture natural convection. Heat transmission has a rather minimal influence on the local Nusselt number for low Grashof and Prandtl values, according to the findings. It gains strength as the Grashof and Prandtl numbers grow, because of the extreme curvature of the isotherms, the maximum value of the local Nusselt number may be found around the corner of the vertical cone in both cones. The current simulations closely match the numerical values provided in the printed matter.

ABSTRAK Dalam kasus tertentu terdapat terowongan percabangan tambang bawah tanah yang tidak teralirkan udara secara mekanis tetapi udara tetap mengalir secara alami teridentifikasi beraliran laminar. Studi ini memodelkan perpindahan momentum aliran laminar udara terowongan dengan dimensi rectangular atau Cartesian untuk memvisualisasikan profil distribusi kecepatan linier fluida dan profil tegangan geser fluida. Metode pemodelan menggunakan perhitungan analitik matematika dari persamaan gerak aliran fluida Newtonian untuk rejim laminar Navier-Stokes. Beberapa data yang dikumpulkan adalah dimensi terowongan, kecepatan linier udara, dan temperatur. Beberapa sifat fisik udara dikutip dari literatur. Hasil pengukuran kecepatan udara rata-rata diinputkan ke dalam model empiris untuk mendapatkan profil koordinat dua dimensi (x,z) untuk distribusi tegangan geser dan kecepatan udara yang mendekati keadaan sebenarnya untuk aliran laminar pada dimensi Cartesian. Hasil penelitian didapatkan pressure drop aliran sebesar 2,2 x 10-5 Pa, aliran mengandalkan perpindahan molekular bukan perpindahan secara konveksi paksa karena dilihat dari profil sebaran tegangan geser yang terlalu kecil dan laju alir sebesar 0,32 m3/s tidak memenuhi fungsi ventilasi tambang bawah. Kata kunci: perpindahan momentum; aliran laminar; fluida newtonian; ventilasi tambang. ABSTRACT In certain case there is a mine tunnel branch that is not mechanically ventilated but air still flow naturally identified as laminar flow. This study modelled the momentum transport of the tunnel air laminar flow with rectangular or Cartesian dimensions to visualize the linear velocity distribution profile of the fluid and the fluid shear stress profile. The modelling method uses analytical mathematical calculations of the Newtonian fluid flow equations of motion for the laminar regime of Navier-Stokes. Some of the data collected are tunnel dimensions, air linear velocity, and temperature. Some physical properties of air are cited from literature. The results of the average air velocity measurement are input into the empirical model to obtain two-dimensional coordinate profiles (x,z) for the shear stress distribution and air velocity that are close to the actual situation for laminar flow in the Cartesian dimension. The results of the study obtained a pressure drop of the flow was 2,2 x 10-5 Pa, the flow using molecular transport instead of forced convection transport because seen from the shear stress distribution profile was too small and the flow rate was 0,32 m3/s did not fulfill the underground mine ventilation function. Keywords: momentum transport; laminar flow; newtonian fluid; mine ventilation.

Gold nanoparticles with specialised properties have been utilised for aesthetic purposes throughout history. These nanoparticles are characterised by their size, aspect ratio, and optical features, available in both spherical and non-spherical forms. Various industries, including food, pharmaceuticals, and water purification, make use of gold nanoparticles. Due to their diverse applications, these nanoparticles are employed in addressing stenosis by managing blood flow. The analytical study focuses on blood flow through a typical catheterised artery with stenosis, considering the influence of microorganisms and gold (AU) nanoparticles. Cylindrical coordinates are employed for the examination of blood vessels, and governing equations with appropriate boundary conditions are developed for the cylindrical artery under the assumption of minor stenosis. The Cauchy-Euler technique is applied to obtain precise solutions to the analytical equations. The results indicate that AU nanoparticles enhance blood flow in arteries through heat emission, regulating the axial velocity of the flow. Graphs representing physical parameters such as velocity, temperature, resistance impedance, shear stress, nanoparticle concentration, and microorganism concentration are plotted. The impact of concentration, velocity, temperature, and other factors is illustrated through various stenoses characterised by the form parameter, stenosis height, and catheter radius. Additionally, the Peclet number and Grashof number are analysed for different physical factors. [ABSTRACT FROM AUTHOR]

The stenosis and non-Newtonian property of the fluid in the blood flow represent the behavior of Herschel-Buckley fluid. In a tapered tube model all the vessels which carry blood towards the tissues are considered as long and its one end slowly tapering cones rather than cylinders. Since the blood flow consist of two regions in which one is central region, consist of concentrated blood cells and its behavior is non-Newtonian and other region is peripheral layer of plasma which represent the Newtonian behavior of fluid motion. In present paper, we have considered the Bingham fluid model and study the flow of blood in a uniform tapered tube and obtained conditions and its variation in various graphs for shear stress and pressure gradient. [ABSTRACT FROM AUTHOR]

Non-edible oils hold great potential as a viable feedstock for bio-lubricant production. Among these oils, castor oil stands out due to its unique hydroxyl group structure. Castor oil finds applications in various fields such as lubrication, dielectrics, and heat transfer. This study focused on investigating the dynamic viscosity and thermal conductivity of castor oil and graphene nanoplatelets/castor oil nanofluids. The nanofluids were synthesized through a two-step process involving the combination of graphene nanoplatelets crystal powder with pure castor oil. Morphological and crystallographic analyses revealed platelet-shaped graphene nanoplatelets with a prominent (002) reflection. Dynamic viscosity measurements were performed using a rheometer at temperatures ranging from 40 °C to 100 °C, and thermal conductivity assessments were conducted using the Modified Transient Plane Source technique from 30 °C to 70 °C. Investigation revealed that as temperature increased, the nanofluids exhibited a significant decrease in dynamic viscosity. Conversely, the dynamic viscosity increased moderately with higher concentrations of graphene nanoplatelets. Importantly, the addition of graphene nanoplatelets did not disrupt the Newtonian flow behavior of castor oil. Furthermore, the study demonstrated a remarkable enhancement in thermal conductivity with increasing concentrations of graphene nanoplatelets. This enhancement can be attributed to the high conductivity of graphene nanoplatelets. Overall, biodegradable graphene nanoplatelets/castor oil nanofluid present promising prospects as an advanced lubricating oil with superior heat transfer properties. This research contributes to the understanding and utilization of nanofluids for effective thermal management applications. [ABSTRACT FROM AUTHOR]

In this study, we investigated the particle separation phenomenon in a microchannel with a T-shaped cross-section, a unique design detailed in our previous study. Utilizing a co-flow system within this T-shaped microchannel, we examined two types of flow configuration: one where a Newtonian fluid served as the inner fluid and a viscoelastic fluid as the outer fluid (Newtonian/viscoelastic), and another where both the inner and outer fluids were Newtonian fluids (Newtonian/Newtonian). We introduced a mixture of three differently sized particles into the microchannel through the outer fluid and observed that the co-flow of Newtonian/viscoelastic fluids effectively separated particles based on their size compared with Newtonian/Newtonian fluids. In this context, we evaluated and compared the particle separation efficiency, recovery rate, and enrichment factor across both co-flow configurations. The Newtonian/viscoelastic co-flow system demonstrated a superior efficiency and recovery ratio when compared with the Newtonian/Newtonian system. Additionally, we assessed the influence of the flow rate ratio between the inner and outer fluids on particle separation within each co-flow system. Our results indicated that increasing the flow rate ratio enhanced the separation efficiency, particularly in the Newtonian/viscoelastic co-flow configuration. Consequently, this study substantiates the potential of utilizing a Newtonian/viscoelastic co-flow system in a T-shaped straight microchannel for the simultaneous separation of three differently sized particles. [ABSTRACT FROM AUTHOR]

In this article, we investigate the motion of two-phase immiscible fluids in the channel with the porous medium in the presence of a magnetic field. Depending on the different levels of permeability, the channel is classified into two regions. The lower region (region-I) consists of non-conducting modified Casson fluid and the upper region (region-II) consist of conducting Newtonian fluid. The external electric field is applied in the region-II and the electroosmotic effect is produced at the wall and the interface region. Due to the interfacial effect, the non-conducting fluid was driven by conducting fluid. To compute the flow dynamic and electric potential nature, the momentum equation and Poisson–Boltzmann equation have been solved analytically in the state of periodic vibrations. The impact of physiological parameters such as Debye–Hückel parameter, electric field, magnetic field, Darcy numbers, viscosity ratio, Casson parameter and Womersley number has been investigated and the various behaviours were characterised. Based on numerical computations performed on the aforementioned parameters, we found that the Casson parameter, Darcy numbers and electric double layer (EDL) effects are predominant features. In the velocity profiles, we identified the flow of the fluid was enhanced by the augmented values of Darcy numbers, electric field (wall zeta potential), Debye–Hückel parameter and Casson parameter. The retardation flow occurred for the higher values of the magnetic field, viscosity ratio and electric field (interface zeta potential). Based on the conditional cases, the Womersley number possesses inconsistent behaviour. The depletion nature was found in the percentage flow rate of the Casson parameter. By increasing the value of the electric field and Casson parameter, the magnitude of wall shear stress to Darcy number increases and decreases for higher values of the magnetic field, viscosity ratio and pulsatile Reynolds number. It is first noticed that for any value of M1 and M2, Darcy number (Da2) plays a dual role in the upper wall shear stress. The present study leads to the pumping effect of gas pipelines or designing the microfluidic devices which are manipulated in biosensors/biochips. [ABSTRACT FROM AUTHOR]

In order to investigate the diffusion mechanism of slurry in post-pile grouting, this study develops a formula for calculating the diameter and the climb height of the cement core of jet grouting (CCJG). This research conducts field orthogonal tests using a self-developed grouting nozzle to analyze the effects of disturbance pressure (DP), disturbance time (DT), grouting pressure (GP), and the water–cement ratio (W/C) on the dimensions and strength of the CCJG. The findings revealed that the theoretical formula for calculating the diameter of the CCJG deviates by approximately 8% from the field test results, confirming the formula’s validity. In addition, the DP and DT significantly influence the volume of the CCJG, displaying a linear increase with their augmentation. Conversely, the W/C and DP predominantly affect the CCJG’s strength. Notably, an increase in the W/C results in diminished strength, whereas an increase in the DP enhances it. In addition, soil reinforcement is achieved through replacement, mixing, and compaction as the grout flows outward from the center of the grouting hole. These insights offer a theoretical foundation and technical support for effective grouting construction practices.

This article investigates the effect of cylindrical obstacles with different dimensions inside the triangular cavity on natural convection heat transfer. This study considers three cavities, each of which has one, two, and three-cylinder barriers embedded inside it. The use of one or two cylindrical barriers has been investigated in many research, but in this research, in addition to the number of cylindrical barriers, their dimensions and sizes have been changed, and an alternating temperature function has been used at the base of the cavity. The considered nanofluid is Al2O3H2O, which contains aluminum oxide nanoparticles with a concentration of 5 %. In all three cavities, the velocity of the nanofluid in the walls is zero. The temperature in the lateral sides of the cavity has low-temperature faces. Instead of being constant or adiabatic, the temperature at its base is an alternating function (sinusoidal function with a frequency of 1.0 Hz.). In contrast, it is considered that the surfaces of the obstacles of the cylinders have zero velocity and are adiabatic. In this study, the governing equations of nanofluid flow behavior have been solved using the Galerkin finite element method and analyzed in the Rayleigh number range of 103 to 105. Because triangular cavities with different ratios are used to optimize multiple objectives and increase thermal performance in microchannels, the results show that the multiplicity of cylindrical obstacles in the triangular cavity causes the expansion of the nanofluid velocity range in the whole area, which itself causes the increase of the heat transfer surface, and with the increase of the Rayleigh number and the buoyancy force, the magnitude of the velocity inside the triangular cavity increases. In the triangular cavity containing three cylindrical barriers, the nanofluid's velocity range is low, but according to the velocity contours, its extent is greater than the other two cavities. Also, the average Nusselt number in this cavity is higher than other cavities.

This study compared the behavior of food boluses describing Newtonian and non-Newtonian fluids through a validated human swallowing simulator based on moving particle simulation. The simulation was qualitatively and quantitatively validated through comparisons with videofluorography images. The positions and configurations of the food boluses and normalized brightness of the simulated and videofluorography images during every timestep were similar, and we thought that the simulator can be used to study the mechanism of food bolus behavior. The validated swallowing simulator results show that the key factors for the optimal design of the thickener are the control of the bolus inflow velocity, which is influenced by rheological and tribological properties, prevention of small splash particles, and bolus discharge flow rate from the epiglottis to the esophagus. In addition, we propose an evaluation index for the degree of bolus coherence based on the bolus flow rate and velocity. [ABSTRACT FROM AUTHOR]

This article aims to introduce a numerical study of two different incompressible Newtonian fluid flows. The first type of flow is through the straight channel, while the second flow is enclosed within a square cavity and the fluid is moved by the upper plate at a specific velocity. Numerically, a Taylor-Galerkin\ pressure-correction finite element method (TGPCFEM) is chosen to address the relevant governing equations. The Naiver-Stoke partial differential equations are usually used to describe the activity of fluids. These equations consist of the continuity equation (conservation of mass) and the time-dependent conservation of momentum, which are preserved in Cartesian coordinates. In this study, the effect of Reynolds number (Re) variation is presented for both problems. Here, the influence of Re on the convergence rate and solution behavior is provided. Findings display that, there is a significant impact of Re upon the temporal convergence rates of velocity and pressure. As well, the rate of convergence increases as the values of Re are risen. For the cavity problem, one can infer that, as the Reynolds number rises, the size of the vortex is reduced. [ABSTRACT FROM AUTHOR]

The fluid kinematics of Liutex decomposes a velocity gradient tensor (VGT) of ∇v into four components, including rotation (R), stretching/compressing (SC), anti-symmetric shear (Santi-sym) and symmetric shear (Ssym), as oppose to the traditional Cauchy-Stokes decomposition where a VGT was decomposed into the strain rate and vorticity tensors. The current study limpidly clarified the physical meanings of these deformations in the newly-proposed decomposition from the perspectives of both fluid kinematics and dynamics. With in-depth understanding the physical connotations of these deformations, the present study further suggests that the Ssym be the only deformation appropriately correlated to the stress tensor, leading to the establishment of a new constitutive relation for Newtonian fluids with the modified model assumptions originated from Stokes in 1845. Moreover, the present research finds that the "principal decomposition" proposed by Liu is not mathematically unique when a VGT has three real eigenvalues (TR). Within the context, a new decomposition method is introduced to avoid the non-uniqueness issue arising from using the principal decomposition to establish fluid dynamics equations. Based on the modified Stokes assumptions and the novel VGT decomposition method, a set of new fluid dynamics momentum equations are obtained for Newtonian fluid. The added stress tensor of Fadd is identified as the key difference between the newly-derived governing equations and the conventional Navier-Stokes (N-S) equations, which is caused by excluding the SC correlation to the stress tensor in the new constitutive equation. Finally, a preliminary analysis of Fadd is conducted using the existing channel turbulence direct numerical simulations (DNS) data based on the traditional N-S equations. The Fadd is found widely existing in turbulence and is of the same order of magnitude with the other force terms. Therefore, the Fadd is expected to have some nonnegligible effects on altering the current DNS data based on the traditional N-S equations, which will be further verified by performing the "DNS" simulation using the newly-derived fluid dynamics equations in near future. [ABSTRACT FROM AUTHOR]

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The energy needed to deform an elastic solid may be recovered, while in Newtonian fluids, like water and glycerol, deformation energy dissipates on timescales of the intermolecular relaxation time τM. For times considerably longer than τM the existence of shear elasticity requires long-range correlations, which challenge our understanding of the liquid state. We investigated laser- driven free surface bubbles in liquid glycerol by analyzing their expansion and bursting dynamics, in which we found a flow- dominating, rubber- like elasticity unrelated to surface tension forces. In extension to findings of a measurable liquid elasticity at even very low deformation frequencies [L. Noirez, P. Baroni, J. Mol. Struct. 972, 16--21 (2010), A. Zaccone, K. Trachenko, Proc. Natl. Acad. Sci. U.S.A. 117, 19653--19655 (2020)], that is difficult to access under increased strain, we find a robust, strain rate driven elasticity. The recovery of deformation energy allows the bursting bubble to reach Taylor--Culick velocities 20- fold higher than expected. The elasticity is persistent for microseconds, hence four orders of magnitude longer than τM. The dynamic shows that this persistence cannot originate from the far tail of a distribution of relaxation times around τM but must appear by frustrating the short molecular dissipation. The longer time should be interpreted as a relaxation of collective modes of metastable groups of molecules. With strain rates of 106 s-1, we observe a metastable glycerol shell exhibiting a rubber- like solid behavior with similar elasticity values and characteristic tolerance toward large strains, although the molecular interaction is fundamentally different. [ABSTRACT FROM AUTHOR]

The current research focuses the light on the characterization of buoyancy-driven non-linear mixed convection and non-linear radiation in a Newtonian flow over a non-linearly stretching vertical sheet, and this type of flow has useful applications in many industrial processes, such as the paper and pulp industry, polymer industry, electronic device cooling, solar collectors, gas turbine plants, and nuclear power. Using appropriate transformations, governing PDEs for non-linear mixed convection are reduced to higher-order non-linear ODEs and those are numerically solved. Along with tabular presentations of computed results, the graphical representations are generated to elucidate the effects of involved parameters on convection transport properties and their inter-relations. It demonstrates that flow velocity increases near the surface and decreases away from the surface as the non-linear convection parameter increases. Furthermore, increments in the thermal buoyancy, temperature ratio and non-linear radiation parameters result in the boost of velocity. The temperature decreases as linear and non-linear buoyancy-related parameters (non-linear convection and thermal buoyancy parameters) are of higher levels. In contrast, the temperature rises with two non-linear thermal radiation-related parameters (thermal ratio and non-linear radiation parameters). For greater values of the non-linear stretching related parameter, a lower velocity and a higher temperature are witnessed. The non-linear convection, thermal buoyancy, thermal ratio and non-linear radiation parameters contribute toward the reduction of the magnitude of surface-drag force and growth of the surface cooling rate. But, with the non-linearity in surface stretching there are significant percentage hikes of surface-drag force magnitude and surface cooling rate.

Efficient transport in vertical pipeline hydraulic lifting systems is vital for coarse-grained ore, necessitating a deep comprehension of the settling traits of coarse mineral particles. In this study, we conducted a series of settling experiments on individual coarse particles in Newtonian fluids with varying viscosities, employing a self-designed and manufactured settling apparatus. A total of 133 sets of experimental data on the free settling of coarse particles in Newtonian fluids were obtained by recording the particle settling process with a high-speed camera and applying image processing techniques. A mechanical model was employed to perform statistical analysis on the experimental data and establish a predictive model for the drag coefficient and an explicit predictive model for the settling terminal velocity of coarse-grained ore in Newtonian fluids. The average relative errors between the predicted values and experimental values of the drag coefficient and settling terminal velocity models are 4.26% and 7.34%, respectively. This confirms the reliability of the provided predicted model, providing a theoretical foundation for determining the hydraulic lifting speed of coarse mineral particles in vertical pipelines for deep mining.

In petroleum engineering, accurately predicting particle settling velocity during various stages of a well’s life cycle is vital. This study focuses on settling velocities of both spherical and non-spherical particles in Newtonian and non-Newtonian fluids. Utilizing a dataset of 931 experimental observations, an artificial neural network (ANN) model with a 7-42-1 architecture is developed (one input layer, one hidden layer with 42 neurons, and one output layer). This model effectively incorporates particle settling orientation and the inclusion of the settling area ratio, enhancing its predictive accuracy. Achieving an average absolute relative error (AARE) of 8.51%, the ANN model surpasses traditional empirical correlations for settling velocities in both Newtonian and power-law fluids. Key influencing factors, such as the consistency index and particle equivalent diameter, were identified. This approach in ANN model construction and data analysis represents a significant advancement in understanding particle dynamics.

Computational fluid dynamics technique have been employed to capture the plain convective flow past from a heated cone with a tip downward in various stagnant Newtonian fluids. Using detailed isotherm patterns around the cone under steady-state conditions examine the heat transfer characteristics that have been reported. The findings illustrate the distribution of the friction factor, average Nusselt number and local Nusselt number around the cone surface over a wide range of dimensionless values such as Grashof and Prandtl numbers. The guiding PDEs such as conservation of mass, momentum and energy are solved by finite volume method using commercial software of ANSYSCFX16.0. To simplify the governing equations while capturing the natural convection, Boussinesq approximation has been adopted to coupling the flow and temperature fields.This study reveals the contribution of various angles (φ = 15°,300and45°), diverse Prandtl numbers (Pr = 0.71,5,10,20,50) and distinct Grashof numbers (GrL = 104, 105, 106) for the efficacy of them over the slant surface of the cone. The heat transmission and parametric features of these processes have been discussed for how heat can be transferred from a heated cone when it is submerged in a liquid. Visualization of the effects of different parameters for different cone apex angles was done by displaying the results graphically. The present simulations are in a near match to the numeric values appeared in the literature.

Numerical simulation was conducted in this study to calculate the agitating torque of the high viscosity Newtonian fluid by the explicit-MPS method using virtual boundary particles for the agitating container and the agitating flapper. At first, a calculation of the resting hydraulic pressure was carried out to confirm the pressure of fluid particles in the vicinity of the flapper. As a result, it was confirmed that the average of the pressure distribution of the fluid particles corresponded with a theoretical value of the resting hydraulic pressure. Considering this result, trial calculation of flapper agitating torque was calculated from the pressure of the fluid particles in the vicinity of the rotated flapper. The flapper agitating torque was calculated from the torque caused by the differential pressure between front and back faces of the flapper and the torque caused by the shear stress of the fluid particle near the flapper edges. From this calculation, stable agitating torques were obtained for each time step at each flapper speed, and consistent with the high viscous Newtonian fluid agitating test results which showed the linear relationship between the number of flapper speed and agitation torque. Furthermore, it was confirmed that the agitation torques were dominated by the torque caused by the pressure between the front and back faces of the flapper.

The present study is established on a simulation using CFD analysis in COMSOL. Blood acted as the base fluid with this simulation. The taken flow is been modeled as incompressible, unsteady, laminar and Newtonian fluid, which is appropriate at high rates of shear. The characteristic of flow of blood is been studied in order to determine pressure, velocity and temperature impact caused by an abdominal aortic aneurysm (AAA). This work employs nanoparticles of the Iron Oxide (Fe3O4) type. The CFD technique is utilized to evaluate the equations of mass, momentum, and energy. The COMSOL software is utilized to generate a normal element sized mesh. The findings of this study demonstrate that velocity alters through aneurysmal part of the aorta, that velocity is higher in a diseased segment, and that velocity increases before and after the aneurysmal region. For the heat transfer feature, the reference temperature and general inward heat flux is taken as 293.15K and 800W/m2. The nanoparticles altered blood's physical properties, including conductivity, dynamic viscosity, specific heat, and density. The inclusion of Iron Oxide (Fe3O4) nanoparticles managed to prevent overheating because taken nanoparticles have significant thermal conductivity. These findings will be extremely beneficial in the treatment of abdominal aortic aneurysm.

Blood is indeed a suspension of the different type of cells along with shear thinning, yield stress and viscoelastic characteristics, which can be expressed by Newtonian and a lot of non-Newtonian models. Choosing Newtonian fluid as a sample, an unsteady solver for Newtonian fluid is constructed to determine the transient flow of blood in the obscure region. In this probe, the computational unsteady flow of blood in artery with aneurysm and symmetric stenosis has been considered, which is novelty of current research. The results of this investigation can be applied to detect stenotic-aneurysmal diseases and enhance knowledge of the stenotic-aneurysmal artery, which may increase the understanding of medical science. The blood artery is modeled as a circular tube having a 0.3-m radius and a 2-m length along the horizontal axis. The velocity of blood is taken at 0.12 ms−1 so that the geometry satisfies the characteristics of the blood vessel. The governing mass and momentum equations are then solved by finite difference technique of discretization. In this research, important variations in blood pressure and velocity at stenosis and aneurysms in the artery are found. The significant influences on blood flow of the stenotic-aneurysmal artery for pressure and velocity profiles of blood are displayed graphically for the Newtonian model.

The escalation of zeta potential by the influence of wall slip for the electrokinetically modulated flow through a microchannel motivates to consider the impact of hydrodynamic slippage upon the zeta or surface potential. The reported study undergoes an analytical exploration of the pulsatile electroosmosis and shear-actuated flow characteristics of a fluid with a Newtonian model through a microchannel with parallel plates by invoking the reliance of a zeta or surface potential on slippage. The linearized Poisson-Boltzmann and momentum equations are solved analytically to obtain the explicit expression of the electrical potential induced in the electrical double layer (EDL), the flow velocity field, and the volumetric flow rate for an extensive span of parameters. The velocity field proximal to the microchannel wall is observed to enhance by an apparent zeta potential, and is further escalated for a thinner EDL and an oscillating electric field with a higher amplitude. However, near the core region of the microchannel, the flow velocity becomes invariant with the EDL thickness. The result shows that the lower wall velocity contributes to the flow velocity along with the electroosmotic body force and the impact of the velocity of the wall underneath diminishes proximal to the upper wall. Moreover, the volumetric flow rate increases when the thickness of the EDL decreases, owing to the influence of the wall slip. However, for thinner EDLs and medium and higher oscillating Reynolds numbers, the volumetric flow rate varies non-monotonously, correlative to the slip-free and slip cases. [ABSTRACT FROM AUTHOR]

The intricate morphology of porous media can considerably affect the progression of penetration and the diffusion of grouting slurry. In this study, a Newtonian fluid's refined seepage motion equation was proposed to incorporate the impact of tortuosity on the grouting process into gravel soil, and the column-hemispherical penetration grouting mechanism was analyzed using the method of theoretical analysis. Utilizing secondary-development programming techniques, a numerical simulation program was developed with COMSOL Multiphysics to model the penetration grouting mechanism of a Newtonian fluid in a column-hemispherical pattern, considering a medium's tortuosity. The penetration grouting process of Newtonian cement into gravel soils was then simulated. Finally, the theoretical analysis, experimental values, and numerically simulated values were compared.The findings suggested that incorporating the tortuosity of porous media is more efficacious in depicting the penetration and diffusion behavior for Newtonian fluid grouting in porous media, as compared to omitting the tortuosity. The findings of this study contribute to a better understanding of grouting engineering in porous media strata, guiding practical design and construction. [ABSTRACT FROM AUTHOR]