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This paper aims to explore the effectiveness and mechanism of a droplet-laden flow in a microfluidic system.

Numerical approach based on the volume of fluid method is implemented for modelling the forced heat transport in a droplet-laden flow in a microchannel.

The heat transfer effectiveness of droplet-laden flow is found to be obviously superior to that of a single-phase flow because of the circulation stream between the droplets. In addition, the effectiveness will be further increased when an elongated droplet is being laden because the circulation streams within and between the droplets are more pronounced. The elongated droplet size affects the heat transfer characteristics signified by Nusselt number, and there exists an optimum value at a fixed parameter.

This paper attempts to clarify the influence on the heat transfer performance when droplet with various shape and size being laden. This work is done by none before. This research work applies a solid foundation for designing a cooling system in microelectromechanical system.

This paper aims to investigate the influence of oil–air lubrication flow behavior on point contact sliding wear characteristics.

Oil–air lubrication equations between point contact counterparts were established on the basis of volume of fluid model. The effects of oil supply and injection azimuth on oil-phase volume fraction and its pressure distribution were simulated with commercial software Fluent. Characteristics of point contact sliding wear were then tested with an MFT-3000 friction tester under oil–air lubrication condition. The influence of flow behavior on wear characteristic was investigated combined with numerical and experimental results. The wear mechanism was revealed using SEM, EDS and ferrography.

When air supply speed is constant, the oil-phase volume fraction increases with the increase in oil supply, which helps form continuous oil film and decrease the sliding wear evidently. The injection angle and distance considerably influence the oil–air flow behavior. When injecting at a certain distance and angle, the oil-phase volume fraction reaches its maximum, and the abrasion loss is minimal. Under the test conditions in this study, abrasive particles are mainly debris and a few spiral cuttings. The wear mechanism is abrasive wear.

The influence of the behavior of oil–air lubrication flow on the characteristic of point contact sliding wear is analyzed. This work provides guidance for the application of oil–air lubrication technology in point contact friction pairs.

The purpose of this paper is to investigate the impact of time-periodic thermal boundary conditions on natural convection flow in a vertical micro-annulus.

Analytical solution in terms of Bessel’s function and modified Bessel’s function of order 0 and 1 is obtained for velocity, temperature, Nusselt number, skin friction and mass flow rate.

It is established that the role of Knudsen number and fluid–wall interaction parameter is to decrease fluid temperature, velocity, Nusselt number and skin friction.

No laboratory practical or experiment was conducted.

Cooling device in electronic panels, card and micro-chips is frequently cooled by natural convection.

In view of the amount of works done on natural convection in microchannel, it becomes interesting to investigate the effect that time-periodic heating has on natural convection flow in a vertical micro-annulus. The purpose of this paper is to examine the impact of time-periodic thermal boundary conditions on natural convection flow in a vertical micro-annulus.

This paper seeks to discuss a mechanistic modeling concept for local phenomena governing two‐ and multi‐phase flows and heat transfer.

An overview is given of selected issues concerning the formulation of multidimensional models of two‐phase flow and heat transfer. A complete computational multiphase fluid dynamics (CMFD) model of two‐phase flow is presented, including local constitutive models applicable to two‐phase flows in heated channels. Results are shown of model testing and validation.

It has been demonstrated that the overall model is capable of capturing various local flow and heat transfer phenomena in general, and the onset of temperature excursion (CHF) in low quality forced‐convection boiling, in particular.

Whereas the multiphase model formulation is applicable to a large class of problems, geometries and operating conditions, the closure laws and results are focused on forced‐convection boiling in heated channels.

The proposed approach can be used to predict multidimensional velocity field and phase distribution in two‐phase flow devices and components used in thermal power plants, nuclear power plants and chemical processing plants.

A complete mechanistic multidimensional model of forced‐convection boiling in heated channels is given. The potential of a CMFD approach is demonstrated to perform virtual experiments that can be used in system design and optimization, and in safety analysis.

The purpose of this study is to present the magnetohydrodynamic (MHD) flow and heat transfer in an accelerating film of a non-Newtonian pseudo-plastic nanofluid along an inclined surface with viscous dissipation and Joule heating.

An incompressible and inelastic fluid is assumed to obey the Ostwald-de-Waele power law model and the action of viscous stresses is confined to the developing momentum boundary layer adjacent to the solid surface. Viscous dissipation and Joule heating on the flow of electrically conducting film in the presence of uniform transverse magnetic field is considered for the Carboxyl Methyl Cellulose (CMC) water-based nanofluid. The fluid is the CMC-water-based with concentration (0.1-0.4 per cent) containing three types of nano-solid particles Cu, Al₂O₃ and TiO₂. The modeled boundary layer conservation equations are transformed to dimensionless, coupled and highly non-linear system of differential equations, and then solved numerically by means of a local non-similarity approach with shooting technique. To validate the numerical results, a comparison of the present results is made with the earlier published results and is found to be in good agreement.

The effects of magnetic parameter, Prandtl number, Eckert number and Biot numbers on the velocity and temperature fields are presented graphically and discussed for various values of thermo-physical parameters. It has been found that magnetic field decelerates the fluid velocity for both cases of Newtonian nanofluid and pseudo-plastic nanofluid because of the generated drag-like Lorentz force. This is of great benefit in magnetic materials processing operations, utilizing static transverse uniform magnetic field, as it allows a strong regulation of the flow field.

The numerical study is valid for two-dimensional, steady, laminar film flow of Ostwald-de-Waele power law non-Newtonian nanofluid along an inclined plate. A uniform transverse magnetic field of strength B₀ is applied perpendicular to the wall. Assume that the base fluid and the nano-solid particles are in thermal equilibrium with no slip effects. The interaction of magnetic field with nanofluid has several potential implications and may be used to deal with the problems such as cooling nuclear reactors by liquid sodium and inducting the flow meter which depends on the potential difference in the fluid along the direction perpendicular to the motion and to the magnetic field.

The study has significant applications in magnetic field control of materials processing systems.

The results of the present study may be attentiveness to the engineers and applied mathematicians who are interested in hydrodynamics and heat transfer enhancement associated with film flows.

The purpose of this paper is to propose an attitude determination and control scheme for a low‐cost Micro‐satellite with defective inertia. Restricted by the payload design, the z‐axis inertia of this satellite is larger than the x and y axes, which is unstable for natural attitude dynamics.

An original operation mode is designed to avoid z axis from long‐time pointing to the sun during damping, which avoids some unexpected damage. In attitude determination design, EKF and UKF algorithms are compared on estimation accuracy, convergence time and computation complexity in attitude estimation design, which is referred to determine the final estimation scheme. A DSP‐based hardware solution is achieved and a semi‐physical testing and simulation system is built.

Simulation results show the 3‐axis stable mode can be built with the proposed scheme, and the unprotected facet of the satellite can be kept away from long‐time pointing to the sun.

The proposed ADCS scheme can be a reference for the future Micro‐satellite programs which share the similar configuration.

The small dimensions of future device designs also imply a stronger effect of material boundary resistance. For nanoscale devices and structures, especially, interface phenomena often dominate their overall thermal behavior. The purpose of this paper is to propose molecular dynamics (MD) simulations to investigate the mechanical and thermal properties at Cu‐Al interface.

The two‐temperature model (TTM)‐MD model is used to describe the electron‐phonon scattering at interface of different metals. Before the simulation of heat transfer process, a non‐ideal Cu‐Al interface is constructed by simulating diffusion bonding.

According to the simulation results, in unsteady state, the temperature distribution and the displacements of atoms near the interface tend to generate stress and voids. It reveals the damage mechanics at the interface in heat transfer.

The atomic model proposed in this paper is computationally efficient for interfacial heat transfer problems, and could be used for investigation of other interfacial behaviors of dissimilar materials.

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

This paper aims to explore the mechanism of the slip phenomenon at macro/micro scales, and analyze the effect of slip on fluid flow and heat transfer, to reduce drag and enhance heat transfer.

The improved tangential momentum accommodation coefficient scheme incorporated with Navier’s slip model is introduced to the discrete unified gas kinetic scheme as a slip boundary condition. Numerical tests are simulated using the D2Q9 model with a code written in C++.

Velocity contour with slip at high Re is similar to that without slip at low Re. For flow around a square cylinder, the drag is reduced effectively and the vortex shedding frequency is reduced. For flow around a delta wing, drag is reduced and lift is increased significantly. For Cu/water nanofluid in a channel with surface mounted blocks, drag can be reduced greatly by slip and the highest value of drag reduction (DR) (67.63%) can be obtained. The highest value of the increase in averaged Nu (11.78%) is obtained by slip at Re = 40 with volume fraction φ=0.01, which shows that super-hydrophobic surface can enhance heat transfer by slip.

The present study introduces and proposes an effective and superior method for the numerical simulation of fluid/nanofluid slip flow, which has active guidance meaning and applied value to the engineering practice of DR, heat transfer, flow control and performance improvement.

The purpose of this paper is to study the integration between fused deposition modeling (FDM) technology and abrasive flow machining process to improve the surface quality of FDM printed parts. FDM process has some limitations in terms of accuracy and surface finish. Hence, post-processing operations are essential to increase the quality of the part.

Initially, a sustainable polymer abrasive gel-based media (SPAGM) using natural polymer and natural additives (waste vegetable oil) was prepared using different combinations of (abrasive mesh size, percentage of abrasives and percentage of liquid synthesizer); then the characterization of media was done to check various properties. As media is an essential part in the process which helps in increase the surface finish, it needs to have some desired characteristics such as the following: the developed SPAG needs to hold the abrasives; its viscosity has to be medium so that it can easily flow through the machine; and its thermal stability caused by the increase in the temperature during various cycles of operation. For that, it is characterized rheologically as well as thermally to find its various properties.

Experiments were performed on FDM-printed parts using an L9 orthogonal array with different parameters to find their effect on the workpiece. Scanning electron microscope images of SGAPM showed sharp edges of abrasive particles and bonding pattern between polymer chain molecules. Good surface finish and material removal rate (MRR) was observed at high pressure and long finishing time with 50 per cent abrasive concentration.

The authors confirm that this work is original and has neither been published elsewhere nor is it currently under consideration for publication elsewhere.