objective(s): this study aims to evaluate and predict the thermal conductivity of iron oxide nanofluid at different temperatures and volume fractions by artificial neural network (ann) and correlation using experimental data. methods: two-layer perceptron feedforward artificial neural network and backpropagation levenberg-marquardt (bp-lm) training algorithm are used to predict the thermal cond...

We used video microscopy and particle tracking to study the dynamics of confined hard-sphere suspensions. Our fluids consisted of 1.1-microm-diameter silica spheres suspended at volume fractions of 0.33-0.42 in water-dimethyl sulfoxide. Suspensions were confined in a quasiparallel geometry between two glass surfaces: a millimeter-sized rough sphere and a smooth flat wall. First, as the separati...

The development of nanocomposites a matrix, often polymeric, enhanced by a particle with a nanometersized dimension has expanded dramatically in recent years with a particular focus on materials with complex microstructure and nanostructure. Such composites rely on formation of a connected network of particles throughout the sample volume in order to enhance the polymer’s mechanical and electri...

We present an in-depth analysis of the geometrical percolation behavior in the continuum of random assemblies of hard oblate ellipsoids of revolution. Simulations were carried out by considering a broad range of aspect ratios, from spheres up to aspect-ratio-100 platelike objects, and with various limiting two-particle interaction distances, from 0.05 times the major axis up to 4.0 times the ma...

The reactive and diffusive dynamics of a single chemically powered Janusmotor in a crowded medium of moving but passive obstacles is investigated using molecular simulation. It is found that the reaction rate of the catalytic motor reaction decreases in a crowded medium as the volume fraction of obstacles increases as a result of a reduction in the Smoluchowski diffusion-controlled reaction rat...

The absorbance and circular dichroism (CD) of suspensions is lower than if the same amount of chromophore were uniformly distributed throughout the medium. Several mathematical treatments of this absorption flattening phenomenon have been presented using various assumptions and approximations. This article demonstrates an alternative simulation approach that allows relaxation of assumptions. On...

The degree of dispersion of short microfibers in cement, as assessed by electrical resistivity measurement for the case of electrically conductive fibers at a volume fraction below the percolation threshold, is improved by the use of admixtures ~namely, silica fume, acrylic particle dispersion, methylcellulose solution, and silane! and fiber surface treatment ~such as ozone treatment!. Acrylic ...

Gas holdup and bubble size are important parameters for simulation and designing in bubble column reactors. Because based on these parameters, the available gas-liquid interfacial area is defined for mass transfer. In this paper, the results of applying magnetic fields on the velocity field and volume fraction of gas holdup are reported. Hydrodynamics of the bubble column in the reactors is inv...

A description of the steps taken to produce a massively parallel code for particle suspension problems using the lattice Boltzmann method is presented. A number of benchmarks based on a binary fluid lattice Boltzmann model are used to assess the performance of the code in terms of the computational overhead required for the particle problem compared with the fluid-only problem, and for the scal...