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This article intends to conduct an analytical simulation for the electroosmosis modulated peristaltic transport of ionic hybrid nano-liquid with Casson model through a symmetric vertical microchannel occupying a homogeneous porous material in the existence of the dominant magnetic field, Hall, and ion-slip currents. The hybrid nano-liquid is acquired by the suspension of silver and silicon dioxide nanoparticles into pure water. The wall slip and convective heating impacts are imposed. The Casson fluid (CF) model is adopted to mimic the rheological behaviour accounting for hybrid nano-liquid. Darcy’s law is applied to evaluate the impact of a porous medium. The Poisson-Boltzmann equation is engaged to accommodate the electric double layer (EDL) in the microchannel. Assumptions of low Reynolds number (LRN), long wavelength (LWL), and Debye-Hückel linearization (DHL) are undertaken to simplify the normalized constitutive equations. Closed-form solutions for the linearized dimensionless resulting equations are achieved by ND-solve code in Mathematica. For a comprehensive physical investigation of the problem under simulation, several graphs are furnished to evaluate the role of emerging thermal and physical parameters in developing the flow patterns and thermal characteristics. Outcomes envisage that Hall, ion-slip, and electro-osmotic parameters have a marked impact on the velocity of the ionic liquid. A decrement in the EDL thickness corresponds to an augmentation in the axial velocity profile in the locality of the channel walls. An increment in radiation parameter results in a demotion in the temperature profile. The pressure gradient is elevated with higher Hall and ion-slip parameters, thermal Grashof number, and electro-osmotic parameter, whereas it is dropped due to higher estimates of Hartmann number. The trapping phenomena under the flow factors are also outlined in brief. The bolus formation is deeply affected by Hall, ion-slip, and electro-osmotic parameters. Outcomes achieved here are expected to shed light on the design and analysis of electro-osmotic pumps, microchannel devices, water filtration and purification processes, DNA analyzers, nanoscale electro-fluid thruster designs in-space propulsion, and many more.

The nanocomposites of monodisperse polystyrene (PS) particles and multi-walled carbon nanotubes (MWNTs) were prepared by latex technology to provide good dispersion of nanotubes in polymer matrix. Two kinds of monodisperse PS particles were synthesized either by emulsion polymerization or by dispersion polymerization. The MWNTs were dispersed in deionized water and mixed with the PS particles, and then PS/MWNT nanocomposites were prepared by freeze-drying and subsequent compression molding. Rheological and electrical properties of these nanocomposites were investigated. Pronounced effect of MWNT incorporation was observed, resulting in larger modulus at lower frequencies when compared to neat PS. The nanocomposite prepared under ultrasonication showed the optimum results providing good dispersion of MWNTs and high electrical conductivity. The effect of PS particle size on electrical conductivity was found to be dependent on the MWNT content incorporated.

This paper presents a numerical simulation of the developing flow and heat transfer of a viscoelastic fluid in a rectangular duct. In fully developed flow of a viscoelastic fluid in a non-circular duct, secondary flows normal to the flow direction are expected to enhance the rate of heat and mass transfer. On the other hand, properties such as viscosity, thermal conductivity, specific heat and relaxation time of the fluid are a function of temperature. Therefore, we developed a numerical model which solves the flow and energy equation simultaneously in three dimensional form. We included several equations of state to model the temperature dependency of the fluid parameters. The current paper is one of the first studies which present a 3D numerical simulation for developing viscoelastic duct flow that takes the dependency of flow parameters to the temperature into account. The rheological constitutive equation of the fluid is a common form of the Phan-Thien Tanner (PTT) model, which embodies both influences of elasticity and shear thinning in viscosity. The governing equations are discretized using the FTCS finite difference method on a staggered mesh. The marker-and-cell method is also employed to allocate the parameters on the staggered mesh, and static pressure is calculated using the artificial compressibility approach during the numerical simulation. In addition to report the results of flow and heat transfer in the developing region, the effect of some dimensionless parameters on the flow and heat transfer has also been investigated. The results are in a good agreement with the results reported by others in this field.

The electrorheological (ER) response of polypyrrole(PPy)-tin oxide nanocomposite ER fluids increased with the increase in the tin oxide/pyrrole weight ratio, particle volume fraction, and electric field strength. The dielectric properties and direct current (dc) conductivity of PPy-tin oxide nanocomposite particles and the dielectric properties of PPy-tin oxide nanocomposite ER fluids agreed with the ER behaviors. The ER behavior of PPy-tin oxide nanocomposite ER fluids was well fitted to τ = 0.0248ϕE 1.5 and showed a transition from that of the polarization model (τ ∼ E 2) to that of the conduction model (τ ∼ E 1.5) depending on the tin oxide/pyrrole weight ratio.

Powder injection molding (PIM) is a promising manufacturing technology for the net-shape production of small, complex, and precise metal or ceramic components. In order to manufacture high quality magnets using PIM, the magneto-rheological (MR) properties of the PIM feedstock, i.e. magnetic powder-binder mixture, should be investigated experimentally and theoretically. The current research aims at comprehensive understanding of the rheological characteristics of the PIM feedstock. The feedstock used in the experiment consists of strontium ferrite powder and paraffin wax. Steady and oscillatory shear tests have been carried out using a plate-and-plate rheometer, under the influence of a uniform magnetic field applied externally. Rheological properties of the PIM feedstock have been measured and characterized for various conditions by changing the temperature, the powder fraction and the magnetic flux density.

In this study, we investigate how the initial solvent concentration can influence the final structure and property of the polymer nanocomposites (PNCs). To produce the PNCs, nanoparticles (NPs) and polymers are first required to disperse in a good solvent and then the dispersing solvent quickly evaporates. Previous studies found that controlling the evaporation rate of solvents or drying conditions of solution can change the structure of PNCs; however, the colloidal stability of the NP-polymer mixtures depending on the solvent concentrations has not been much considered. In the NP-polymer colloidal mixture as a precursor system of PNC, the microstructure of the NP dispersion is determined by the net interaction between particles, which may sensitively vary depending on the polymer/solvent concentration. The evaporation of the solvent accompanying the PNC manufacturing process results in a continuous change in the component concentration, which means that the interaction between particles can be continuously changed. We found that the varying initial concentrations in NP-polymer mixtures with different amount of the solvent indeed changes the initial dispersion state of the NPs, which ultimately determined the final microstructure and the physical properties of the PNCs.