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Owing to the technology growth, especially in Microsystems technology and Nanotechnology, new products will provide new ways to sense variables that are crucial for product improvement and system reliability. A big concern of the scientific community is the measurement of low level flow measurements, especially for the biomedical and/or systems on a chip approaches.Design/methodology/approach – A new flow meter concept design consists of a surface micromachined sensor having an optical high reflective mirror made of gold, which is attached to unique cantilever designs that bend due to the drag force of mass flow. The bending of the cantilevers produces the mirror to approach/depart from an optical fiber end‐tip. The reflective light to fiber is modulated using a Fabry‐Perot interferometry technique to determine the mirror separation to the fiber, which corresponds to the mass flow.Findings – The new concept design shows a big potential approach to measure low flow measurements for air, gas and liquids of low viscosity. The results of this concept, through finite element analysis, show that the material used to build the sensor, makes them excellent candidates for fabrication. The stresses of the materials and allowable (readable) bending are among the tolerances of such materials/construction‐design. The sensor is not affected by electromagnetic interference and does not require electrical currents to sense, i.e. it is perfectly suited for biomedical and low mass‐flow sensing such as lab‐on‐chip applications.Originality/value – Among all approaches to sense low flow measurements, most of them need either “big” turbine approaches (dimensions over 1 cm diameter), or the need of an electrical approach needed in the end measurement sensor. This work proposes a non‐electrical approach.

The purpose of this paper is to show how simulation of the flow of particulates and fluids using discrete element modelling (DEM) and smoothed particle dynamics (SPH) particle methods, offer opportunities for better understanding the dynamics of flow processes.

DEM and SPH methods are demonstrated in a broad range of computationally‐demanding applications including comminution, biomedical, geophysical extreme flow events (risk/disaster modelling), eating of food by humans and elite water‐based sports.

DEM is ideally suited to predicting industrial and geophysical applications where collisions between particles are the dominant physics. SPH is highly suited to multi‐physics fluid flow applications in industrial, biophysical and geophysical applications. The advantages and disadvantages of these particle methods are discussed.

Research results are limited by the numerical resolution that can currently be afforded.

The paper demonstrates the use of particle‐based computational methods in a series of high value applications. Enterprises that share interests in these applications will benefit in their product and service development by adopting these methods.

The ability to model disasters provides governments and companies with the opportunity and obligation to use these to render knowable disasters which were previously considered unknowable. The ability to predict the breakdown of food during eating opens up opportunities for the design of superior performing foods with lower salt, sugar and fat that can directly contribute to improved health outcomes and can influence government food regulatory policy.

The paper extends the scale and range of modelling of particle methods for demanding leading‐edge problems, of practical interest in engineering and applied sciences.

Numerous researchers have probed the peristaltic flows because of their immense usage in industrial engineering, biomedical engineering and biological sciences. However, the investigation of peristaltic flow in two-phase fluid of a rotating frame in the presence of a magnetic field has not been yet discussed. Therefore, to fulfill this gap in the existing literature, this paper will explicate the peristaltic flow of two-phase fluid across a rotating channel with the effect of wall properties in the presence of a magnetic field. The purpose of this study is to investigate the two-phase velocity distribution and rotation parameter when magneto-hydrodynamics is applied.

The constituent equations are solved under the condition of low Reynolds number and long wavelength. The exact method is used to attain the subsequent equations and a comprehensive graphical study for fluid phase, particulate phase velocity and flow rates are furnished. The impacts of pertinent parameters, magnetic field and rotation are discussed in detail.

It is witnessed that the velocity profile of particulate phase gets higher values for the same parameters as compared to the fluid phase velocity. Moreover, the axial velocity increases with different values of particle volume fraction, but in case of magnetic field and rotation parameter, it shows the opposite behavior.

The outcomes of study have viable industrial implementations in systems comprising solid-liquid based flows of fluids involving peristaltic movement.

The investigation of peristaltic flow in two-phase fluid of a rotating frame in the presence of a magnetic field has not been yet discussed. Therefore, to fulfill this gap, the present study will explicate the peristaltic flow of two-phase fluid across a rotating channel with the effect of wall properties in the presence of magnetic field.

This study aims to investigate the impact of different heater geometries (flat, rectangular, semi-elliptical and triangular) on hybrid nanofluidic (Cu–Al₂O₃–H₂O) convection in novel umbrella-shaped porous thermal systems. The system is top-cooled, and the identical heater surfaces are provided centrally at the bottom to identify the most enhanced configuration.

The thermal-fluid flow analysis is performed using a finite volume-based indigenous code, solving the nonlinear coupled transport equations with the Darcy number (10^–5 ≤ Da ≤ 10^–1), modified Rayleigh number (10 ≤ Ra_m ≤ 10⁴) and Hartmann number (0 ≤ Ha ≤ 70) as the dimensionless operating parameters. The semi-implicit method for pressure linked equations algorithm is used to solve the discretized transport equations over staggered nonuniform meshes.

The study demonstrates that altering the heater surface geometry improves heat transfer by up to 224% compared with a flat surface configuration. The triangular-shaped heating surface is the most effective in enhancing both heat transfer and flow strength. In general, flow strength and heat transfer increase with rising Ra_m and decrease with increasing Da and Ha. The study also proposes a mathematical correlation to predict thermal characteristics by integrating all geometric and flow control variables.

The present concept can be extended to further explore thermal performance with different curvature effects, orientations, boundary conditions, etc., numerically or experimentally.

The present geometry configurations can be applied in various engineering applications such as heat exchangers, crystallization, micro-electronic devices, energy storage systems, mixing processes, food processing and different biomedical systems (blood flow control, cancer treatment, medical equipment, targeted drug delivery, etc.).

This investigation contributes by exploring the effect of various geometric shapes of the heated bottom on the hydromagnetic convection of Cu–Al₂O₃–H₂O hybrid nanofluid flow in a complex umbrella-shaped porous thermal system involving curved surfaces and multiphysical conditions.

This paper aims to simulate the steady laminar mixed convection incompressible viscous and electrically conducting hybrid nanofluid (CuO-Cu/blood) flow near the plane stagnation-point over a horizontal porous stretching sheet along with an external magnetic field and induced magnetic field effects that can be applicable in the biomedical fields like the flow dynamics of the micro-circulatory system and especially in drug delivery.

The basic partial differential equations (PDEs) are altered to a set of dimensionless ordinary differential equations (ODEs) with the help of suitable similarity variables which are then solved numerically using bvp4c scheme from MATLAB. Inasmuch as validation results have shown a good agreement with previous reports, the present novel mass-based algorithm can be used in this problem with great confidence. Governing parameters are both nanoparticle masses, base fluid mass, empirical shape factor of both nanoparticles, suction/injection parameter, magnetic parameter, reciprocal magnetic Prandtl number, Prandtl number, heat source parameter, mixed convection parameter, permeability parameter and frequency ratio. The effect of these parameters on the flow and heat transfer characteristics of the problem is discussed in detail.

It is shown that the use of CuO and Cu hybrid nanoparticles can reduce the hemodynamics effect of the capillary relative to pure blood case. Moreover, as the imposed magnetic field enhances, the velocity of the blood decreases. Besides, when the blade shapes for both nanoparticles are taken into account, the local heat transfer rate is maximum that is also compatible with experimental observations.

An innovative mass-based model of CuO-Cu/blood hybrid nanofluid has been applied. The novel attitude to one-phase hybrid nanofluid model corresponds to considering nanoparticles mass as well as base fluid mass to computing the solid equivalent volume fraction, the solid equivalent density and also solid equivalent specific heat.

A precise and rapid temperature cycling of a small volume of fluid is vital for an effective DNA replication process using the polymerase chain reaction (PCR). The purpose of this paper is to study the velocity and temperature fields inside a rotating PCR‐tube during cooling of the enclosed liquid.

The velocity and temperature fields inside a rotating PCR‐tube during cooling of the enclosed liquid are studied. By using computational fluid dynamics, the time development of the flow can be investigated in detail. Owing to the rotation, the flow exhibits features which could never arise in a non‐rotating system.

An intricate azimuthal boundary layer flow is presented and explained. The inherent problem of stratification of the temperature is discussed, and different methods towards a remedy are presented. By analyzing the governing equations, some properties of the flow observed in the simulations are explained. It is shown that increasing the rate of rotation does not improve temperature homogenization.

The simulations were performed for a limited number of temperature boundary conditions, as well as a specific simulation geometry.

The analytical and simulation results offer fundamental insight into the physics behind increased DNA duplication. Further simulations offer possible design improvements.

While many studies have probed the effects of buoyancy in rotating cylinders and the development of boundary layers in stratified flows in conical containers rotating around their axis of symmetry, little work has been specifically focused on the case where the axis of rotation is normal to the direction of the stratification, which is the case in the present study.

The purpose of this paper is to numerically study blood flow through a subject‐specific carotid artery with a moderately severe stenosis, also to thoroughly analyse the wall shear stress (WSS), oscillatory shear index (OSI) and WSS angular deviation (WSSAD). One of the important aspects of this study is the investigation on the influence of the extensions attached to the domain outlets.

The segmentation of the carotid artery is carried out using a deformable model based on a level set method. A geometric potential force (GPF) is employed to deform the level set to obtain the carotid artery geometry. The initial surface meshing is generated using an advanced marching cubes (MC) method, before improving the quality of the surface mesh via a number of mesh cosmetic steps. The volume mesh generation has two parts. In the first part, a quasi‐structured, boundary layer mesh is generated in the vicinity of the geometry walls. The second part of the meshing involves unstructured tetrahedral meshing of the inner part of the geometry. After the meshing stage, the flow boundary conditions are generated by numerically solving the Helmholtz equation in both space and time. Finally, the explicit characteristic‐based split (CBS) method is employed in a parallel environment to produce a detailed analysis of wall quantities.

In general, WSS is very high in the vicinity of the carotid artery apex and in the proximity of the stenosis. From the results obtained, it is clear that the influence of outlet domain extension is marginal. While the peak instantaneous WSS differs by a maximum of 5.7 per cent, the time‐averaged WSS difference due to extended domain is only 1.3 per cent. Two other derived parameters are also examined in the paper, the oscillating shear index and the WSSAD. Both these quantities also display minor or negligible differences due to domain extension.

It has been perceived that domain extension is essential to avoid wrong application of boundary conditions. The results obtained, however, conclusively show that the outlet domain extension has only a moderate influence on WSS. Thus, outlet extension to the domains may not be essential for arterial blood flows. It is also observed that the dramatic values of peak WSS obtained near the stenosis is the result of high resolution mesh along with boundary layers used in this study. Both the outcomes represent the originality of this paper.

The performance of three frequently used level set-based segmentation methods is examined for the purpose of defining features and boundary conditions for image-based Eulerian fluid and solid mechanics models. The focus of the evaluation is to identify an approach that produces the best geometric representation from a computational fluid/solid modeling point of view. In particular, extraction of geometries from a wide variety of imaging modalities and noise intensities, to supply to an immersed boundary approach, is targeted.

Two- and three-dimensional images, acquired from optical, X-ray CT, and ultrasound imaging modalities, are segmented with active contours, k-means, and adaptive clustering methods. Segmentation contours are converted to level sets and smoothed as necessary for use in fluid/solid simulations. Results produced by the three approaches are compared visually and with contrast ratio, signal-to-noise ratio, and contrast-to-noise ratio measures.

While the active contours method possesses built-in smoothing and regularization and produces continuous contours, the clustering methods (k-means and adaptive clustering) produce discrete (pixelated) contours that require smoothing using speckle-reducing anisotropic diffusion (SRAD). Thus, for images with high contrast and low to moderate noise, active contours are generally preferable. However, adaptive clustering is found to be far superior to the other two methods for images possessing high levels of noise and global intensity variations, due to its more sophisticated use of local pixel/voxel intensity statistics.

It is often difficult to know a priori which segmentation will perform best for a given image type, particularly when geometric modeling is the ultimate goal. This work offers insight to the algorithm selection process, as well as outlining a practical framework for generating useful geometric surfaces in an Eulerian setting.

The purpose of this paper is to numerically model forced convection heat transfer within a patient‐specific carotid bifurcation and to examine the relationship between the temperature and wall shear stress.

The procedure employs a parallel, fully explicit (matrix free) characteristic based split scheme for the solution of incompressible Navier‐Stokes equations.

The arterial wall temperature, rather than the blood temperature dominates the regions of low wall shear stress and high oscillating shear stress. Additionally, negligible temperature gradient was detected proximal to the arterial wall in this locality.

The presented results demonstrate a possible mechanism for cold air temperature to influence the atherosclerotic plaque region proximal to the stenosis. The proposed patient‐specific heat transfer analysis also provides a starting point for the investigation of the influence of induced hypothermia on carotid plaque and its stability.

The purpose of this paper is to investigate the geometric effects and pulsatile characteristics during the stenotic flows in tapering arteries.

The low Reynolds number k − ω turbulence model is applied to describe the stenotic flows in the tapering arteries in this paper. The results are divided into two sections. The first section characterizes the geometric effects on the turbulent flow under steady condition. The second section illustrates the key physiological parameters including the pressure drop and wall stress during the periodic cycle of the pulsatile flow in the arteries.

The tapering and stenoses severity intensify the turbulent flow and stretch the recirculation zones in the turbulent arterial flow. The wall shear stress, pressure drop and velocity vary most intensively at the peak phase during the periodic cycle of the pulsatile turbulent flow.

This paper provides a comprehensive understanding of the spatial‐temporal fluid dynamics involved in turbulent and transitional arterial flow with stenoses. The low Reynolds number k − ω turbulence model method is applied for the analyses of the geometric effects on the arterial flow and fluid feature during the periodic cycle.