Numerous Engineering Fields Research Articles

A flexible multiscale algorithm based on an improved smoothed particle hydrodynamics method for complex viscoelastic flows

Viscoelastic flows play an important role in numerous engineering fields, and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the nonlinear dynamic behaviors of viscoelastic fluids. However, traditional grid-based multiscale methods are confined to simple viscoelastic flows with short relaxation time, and there is a lack of uniform multiscale scheme available for coupling different solvers in the simulations of viscoelastic fluids. In this paper, a universal multiscale method coupling an improved smoothed particle hydrodynamics (SPH) and multiscale universal interface (MUI) library is presented for viscoelastic flows. The proposed multiscale method builds on an improved SPH method and leverages the MUI library to facilitate the exchange of information among different solvers in the overlapping domain. We test the capability and flexibility of the presented multiscale method to deal with complex viscoelastic flows by solving different multiscale problems of viscoelastic flows. In the first example, the simulation of a viscoelastic Poiseuille flow is carried out by two coupled improved SPH methods with different spatial resolutions. The effects of exchanging different physical quantities on the numerical results in both the upper and lower domains are also investigated as well as the absolute errors in the overlapping domain. In the second example, the complex Wannier flow with different Weissenberg numbers is further simulated by two improved SPH methods and coupling the improved SPH method and the dissipative particle dynamics (DPD) method. The numerical results show that the physical quantities for viscoelastic flows obtained by the presented multiscale method are in consistence with those obtained by a single solver in the overlapping domain. Moreover, transferring different physical quantities has an important effect on the numerical results.

Adaptation of nanofluids with magnetohydrodynamic Williamson fluid to enhance the thermal and solutal flow analysis with viscous dissipation: A numerical study

The Williamson nanofluid flow along with the thermal and solutal transport effects like enthalpy and viscous dissipation, has lots of applications in numerous engineering fields such as heat exchangers, automotive engineering, cooling systems, aerospace, and biomedical applications. The temperature-dependent viscosity has implications in the polymer processing, chemical processing, microfluidic devices, environmental fluid dynamics, and oil and gas industries. The current research deals with the numerical study of the magnetohydrodynamic flow of 2-dimensional Williamson nanofluid flowing on a stretched cylinder. The thermophysical property (viscosity) is assumed to depend on temperature for this flow system. The transmission analysis of solutal and heat processes, along with enthalpy and viscous dissipation, is also considered here. The boundary layer approach is used to address the main leading equations, and ODEs are generated from the main equations by assuming similarity transformations. The main novelty of this problem is the use of a multistep technique, which is the Adams-Bashforth Predictor and Corrector method, along with the RK-4 scheme and the secant method. The key parameters are used to illustrate the graphical and numerical behavior of the velocity, temperature, and concentration regions. The variations in the Williamson fluid coefficient cause the fluid velocity to increase, whereas alterations in the curvature parameter cause the velocity region to decrease. The temperature in a given area declines due to the impact of the Prandtl number. The fluids temperature shows augmented values in the occurrence of variation in the thermopherosis coefficient, Brownian motion coefficient, curvature parameter, and heat generation parameter. The curvature parameter, thermopherosis coefficient, and activation energy lead to an increase in the fluid concentration region, whereas a decrease in concentration is noted due to the Brownian motion coefficient, Damkholer number and Schmidt number.

Recent progress in low‐swellable polymer‐based smart photonic crystal sensors

AbstractLow‐swelling polymers (LSPs) generally refer to materials with a low solvent absorption ratio or volume expansion rate at swelling equilibrium. LSPs with exceptional responsiveness could be upgraded to smart sensors with structural color self‐reporting by bridging photonic crystals (PCs). Based on the regulation of swelling to effective refractive index, lattice spacing, the order‐disorder arrangement of nanostructures, and incident/detection angle, the structural color feedback of smart photonic crystal sensors (SPCSs) can quantitatively and visually reveal the stimulus, which greatly promotes the interdisciplinary development of nanophotonic technology in the fields of chemical engineering, materials science, engineering mechanics, biomedicine, environmental engineering, etc. Herein, to clarify the role of the photonic structures and polymer molecules in high‐performance SPCSs, LSP‐based SPCSs are summarized and discussed, including general swelling mechanisms, color change strategies, structural design, and typical functional applications. It aims to figure out the combination rule between PC structures and LSPs, optimize the design of PC structures, and expound the corresponding structural color sensing mechanisms, inspiring the fabrication of next‐generation SPCSs. Finally, perspectives on future structural design and sensing applications are also presented. It is believed that SPCSs are multifunctional nanophotonic tools for the interdisciplinary development of numerous engineering fields in the future.

Sisko nanofluid flow through exponential stretching sheet with swimming of motile gyrotactic microorganisms: An application to nanoengineering

Abstract The swimming of motile gyrotactic microorganism’s phenomenon has recently become one of the most important topics in research due to its applicability in biotechnology, many biological systems, and numerous engineering fields. The gyrotactic microorganisms improve the stability of the nanofluids and enhance the mass/heat transmission. This research investigates the MHD fluid flow of a dissipative Sisko nanofluid containing microorganisms moving along an exponentially stretched sheet in the current framework. The mathematical model comprises equations that encompass the preservation of mass, momentum, energy, nanoparticle concentration, and microorganisms. The equations that govern are more complicated because of nonlinearity, and therefore to obtain the combination of ordinary differential equations, similarity transformations are utilized. The numerical results for the converted mathematical model are carried out with the help of the bvp4c solver. The resulting findings are compared to other studies that have already been published, and a high level of precision is found. The graphical explanations for velocity, temperature, and nanoparticles volume fraction distribution are shown with physical importance. Physical characteristics like Peclet number, Sisko fluid parameter, thermophoresis and Brownian motion parameter, and Hartmann number are taken into consideration for their effects. Based on the numerical outcomes, the bioconvection Peclet number enhances the density of mobile microorganisms, whereas thermal radiation contributes to an elevation in temperature. The velocity field decreases with the enhancement of magnetic parameter; however, the temperature field increases with increased magnetic parameter and thermophoresis parameter augmentation. Our numerical findings are ground breaking and distinctive, and they are used in microfluidic devices including micro instruments, sleeve electrodes, and nerve development electrodes. This study has various applications in nanoengineering, including nanomaterial synthesis, drug delivery systems, bioengineering, nanoscale heat transfer, environmental engineering.

High accuracy key feature extraction approach for the non-stationary signals measurement based on NGO-VMD noise reduction and CNN-LSTM

The effective extraction of key features in non-stationary signals measurement is crucial in numerous engineering fields, including fault diagnosis, geological exploration, and state detection. To accomplish a more accurate and efficient extraction of key feature information from non-stationary signals, we design a novel approach based on variational mode decomposition (VMD) optimization by northern goshawk optimization (NGO) algorithm, convolutional neural network (CNN), and long short-term memory network (LSTM). First, NGO is used to optimize multiple intrinsic mode functions of VMD and reconstruct the signal according to the linear correlation method. Subsequently, the features of moving root mean square, moving kurtosis, and upper envelope are calculated, thereby constructing the feature matrix. Finally, the CNN-LSTM model is established with the chosen optimal hyperparameters prior to the training phase. The experimental results demonstrate that the proposed NGO-VMD-CNN-LSTM method, with a high accuracy reaching 98.22%, can more accurately extract the key information of typical non-stationary signals.

Elucidating Interfacial Dynamics of Ti-Al Systems Using Molecular Dynamics Simulation and Markov State Modeling.

Due to their remarkable mechanical and chemical properties, Ti-Al-based materials are attracting considerable interest in numerous fields of engineering, such as automotive, aerospace, and defense. With their low density, high strength, and resistance to corrosion and oxidation, these intermetallic alloys and metal-compound composites have found diverse applications. However, additive manufacturing and heat treatment of Ti-Al alloys frequently lead to brittleness and severe formation of defects. The present study delves into the interfacial dynamics of these Ti-Al systems, particularly focusing on the behavior of Ti and Al atoms in the presence of TiAl3 grain boundaries under experimental heat treatment conditions. Using a combination of molecular dynamics and Markov state modeling, we scrutinize the kinetic processes involved in the formation of TiAl3. The molecular dynamics simulation indicates that at the early stage of heat treatment, the predominating process is the diffusion of Al atoms toward the Ti surface through the TiAl3 grain boundaries. Markov state modeling identifies three distinct dynamic states of Al atoms within the Ti/Al mixture that forms during the process, each exhibiting a unique spatial distribution. Using transition time scales as a qualitative measure of the rapidness of the dynamics, it is observed that the Al dynamics is significantly less rapid near the Ti surface compared to the Al surface. Put together, the results offer a comprehensive understanding of the interfacial dynamics and reveal a three-stage diffusion mechanism. The process initiates with the premelting of Al, proceeds with the prevalent diffusion of Al atoms toward the Ti surface, and eventually ceases as the Ti concentration within the mixture progressively increases. The insights gained from this study could contribute significantly to the control and optimization of manufacturing processes for these high-performing Ti-Al-based materials.

Reactor physics characterization of triply periodic minimal surface-based nuclear fuel lattices

Triply periodic minimal surface (TPMS) lattices are receiving substantial attention in numerous engineering fields due to their impressive topology-driven physical characteristics. TPMS lattices are periodic structures of two distinct intertwined volume domains separated by an area-minimizing surface or wall. TPMS lattices have been observed in nature, such as biological membranes, skeletons, block copolymers, sea urchins, butterfly wings, and equipotential surfaces in crystals. Intriguingly, the topology of TPMS lattices can be easily parametrized via level-set equations and thus are heavily numerically and experimentally studied. A significant research effort is currently applying TPMS lattices for heat exchangers and sinks. This paper extends TPMS lattice applications to nuclear reactor fuel designs, with a focus on identifying relevant TPMS geometric parameters controlling neutronics characteristics, such as reactivity, neutron spectrum, and heat removal properties. We found that fuel surface-area-to-volume ratios for TPMS lattices can be two orders of magnitude larger than current cylindrical fuel rods. Further, the selected TPMS lattice and its implicit equation, the unit cell pitch, wall thickness, and structure porosity are design parameters enabling neutronics optimization for both thermal and fast spectrum configurations, paving the way for exceptionally compact and dense nuclear core concepts.

Inverse Estimation of Transient Heat Flux Using Sequential Function Specification Method

Knowledge of surface heat flux is of great importance to numerous engineering fields. In this study, the sequential function specification method (SFSM) was employed to estimate the transient heat flux on the surface of semitransparent medium. The coupled radiation and conduction heat transfer was solved by discrete ordinate method combined with finite volume method. The temperature was used as input in estimation task which was solved by SFSM. Different types of heat fluxes were taken into account to test performance of the present technique. Retrieval results illustrated that the transient heat flux can be accurately determined using the SFSM. It was proved to be effective for different semitransparent media. For the heat flux with drastic changes, the SFSM showed some limitations. Moreover, the influences of future time step and measurement error on determination results were investigated. The SFSM was applicable even when the random deviation was increased to 1.5. The future time step of SFSM is suggested to be 3 for the estimation of transient heat flux on semitransparent medium surface.

Investigation of biphilic microgroove surface on condensation Enhancement: A 3D Lattice Boltzmann method study

• A 3D LBM model with novel boundary scheme is developed. • Droplet critical sliding radius is adopted for optimum microgroove design. • Suction and bridging mode are analyzed to unravel the enhancement mechanisms. • Biphilic microgroove surfaces enhance suction mode and inhibit bridging mode. Condensation heat transfer enhancement is valued in numerous engineering fields for the goal of carbon neutrality. Surface modification provides a passive approach for sustainable dropwise condensation, which is crucial for the enhancement. Microgroove surfaces have received much attention among various modified surfaces due to their excellent droplet nucleation and removal ability. Therefore, to elucidate the enhancement mechanisms and determine the optimum microgroove geometry design, a 3D Lattice Boltzmann Method model is developed in this study. A three-layered hybrid boundary scheme is proposed with better numerical stability. The effect of wettability, groove geometry, and orientation are studied for mechanism analysis. Results show that suction and bridging modes are two major droplet behaviors on microgroove surfaces. The suction mode can accelerate the droplets’ sliding-off process and lead to a smaller departure radius, while the bridging mode could deteriorate the enhancement performance by causing strip-like liquid films. Based on theoretical and simulation results, optimum geometry is proposed under the range of 1 ≤ W G ∗ ≤ 2 , 0 ≤ S G ∗ ≤ 2 , sin ( π - θ ) W G ∗ + S G ∗ > 2 sin ( π - θ ) , and D G ∗ ≅ 1 + sin ( θ - π / 2 ) . The heat flux of the best case is enhanced by 126.9% compared with the result of a plain hydrophobic surface. Furthermore, the enhancement performance of biphilic microgroove surfaces with hydrophilic grooves is discussed. It is found that the suction mode is enhanced while the bridging mode is inhibited, which leads to superior enhancement performance of 140.4% even compared with pure hydrophobic microgroove surface. Finally, surface orientation is studied to analyze the biphilic microgrooves’ condensation enhancement. The downward-facing surface can suppress the suction mode inside the hydrophilic regions and enhance direct departure behaviors on the hydrophobic ridge regions. These conclusions provide a valuable guide for surface modification design and unraveling the enhancement mechanisms.

The 100th Anniversary of the Timoshenko–Ehrenfest Beam Model

The 100th Anniversary of the Timoshenko–Ehrenfest Beam Model

Cyber Secure Framework for Smart Agriculture: Robust and Tamper-Resistant Authentication Scheme for IoT Devices

Internet of Things (IoT) as refers to a network of devices that have the ability to connect, collect and exchange data with other devices over the Internet. IoT is a revolutionary technology that have tremendous applications in numerous fields of engineering and sciences such as logistics, healthcare, traffic, oil and gas industries and agriculture. In agriculture field, the farmer still used conventional agriculture methods resulting in low crop and fruit yields. The integration of IoT in conventional agriculture methods has led to significant developments in agriculture field. Different sensors and IoT devices are providing services to automate agriculture precision and to monitor crop conditions. These IoT devices are deployed in agriculture environment to increase yields production by making smart farming decisions and to collect data regarding crops temperature, humidity and irrigation systems. However, the integration of IoT and smart communication technologies in agriculture environment introduces cyber security attacks and vulnerabilities. Such cyber attacks have the capability to adversely affect the countries’ economies that are heavily reliant on agriculture. On the other hand, these IoT devices are resource constrained having limited memory and power capabilities and cannot be secured using conventional cyber security protocols. Therefore, designing robust and efficient secure framework for smart agriculture are required. In this paper, a Cyber Secured Framework for Smart Agriculture (CSFSA) is proposed. The proposed CSFSA presents a robust and tamper resistant authentication scheme for IoT devices using Constrained Application Protocol (CoAP) to ensure the data integrity and authenticity. The proposed CSFSA is demonstrated in Contiki NG simulation tool and greatly reduces packet size, communication overhead and power consumption. The performance of proposed CSFSA is computationally efficient and is resilient against various cyber security attacks i.e., replay attacks, Denial of Service (DoS) attacks, resource exhaustion.

Effects of vertical confinement on the flow of polymer solutions in planar constriction microchannels.

The flow of polymer solutions under extensional conditions is frequently encountered in numerous engineering fields. Planar contraction and/or expansion microchannels have been a subject of interest for many studies in that regard, which, however, have mostly focused on shallow channel structures. We investigate here the effect of changing the depth of contraction-expansion microchannels on the flow responses of three types of polymer solutions and water. The flow of viscoelastic polyethylene oxide (PEO) solution is found to become more stable with suppressed vortex formation and growth in the contraction part while being less stable in the expansion part with the increase of the channel depth. These opposing trends in the contraction and expansion flows are noted to have similarities with our recent findings of constriction length-dependent instabilities in the same PEO solution (M. K. Raihan, S. Wu, Y. Song and X. Xuan, Soft Matter, 2021, 17, 9198-9209), where the contraction flow gets stabilized while the expansion flow becomes destabilized with the increase of the constriction length. In contrast, the entire flow becomes less stable in deeper channels for the shear-thinning xanthan gum (XG) solution as well as the shear thinning and viscoelastic polyacrylamide (PAA) solution. This observation aligns with that of water flow, which is attributed to the reduced top/bottom wall stabilizing effects.

Stability Analysis of a Planetary Gear Train Having Repeated Natural Frequencies

A Planetary gear trains (PGTs) are widely used in numerous engineering fields, such as automotive, aerospace, and wind turbines, etc. In the dynamic model of geared systems, the time-varying meshing stiffness causes parametric resonances or instability. This paper investigates the instability caused by the time changing meshing stiffness in a PGTs with three symmetrically arranged planet gears. Focus is placed on the instability related to the repeated natural frequencies. The multiple scales method is used in the analysis, and the analytical results are verified with numerical simulation based on Floquet theory.

Effects of crack location and depths for an iron bar: A Finite Element approach

Structural Health Monitoring has become a significant issue in numerous engineering fields and industries. Early detection of damage such as cracks, as well as their depth and location, could be a major research topic. In this research, the natural frequency of a cylindrical solid shapes iron bar together with two half-circle surface crack has been investigated by Finite Element Method (FEM). Vibration Analysis has been used to predict response and different crack depths are the main parameters for analysis to access structural integrity performance of the domain. It is found that lowest frequency of intact bar was higher than the lowest frequency of the cracked bar, and frequencies decreased as the crack depth increased. Using this method very small sizes crack (minimum 0.05 mm) can be defined in any structural body.

Influence of bioceramic reinforcement on tribological behaviour of aluminium alloy metal matrix composites: experimental study and analysis

Composite materials have become inevitable in many current day engineering applications. Aluminium alloy based composites were used in numerous fields of engineering and technology owing to their enormous advantages including low processing cost and broader scope of application. Developing a sustainable bio composite has become the order of the day to mitigate associated environmental issues. In line with this, current experimental work aims to develop a seashell powder reinforced aluminium alloy 2219 composites and determine their mechanical and tribological behaviour. Composites were fabricated using conventional casting with 1, 2 and 3% by weight of seashell powder in aluminium alloy matrix. Chemical constituents present in seashell powder were determined by using X-ray Diffraction studies. Cast composites were subjected to energy dispersive X-ray spectroscopy to witness the formation of any secondary elements. Influence of seashell powder content over hardness and tribological behaviour of aluminium alloy 2219 composites were analysed by conducting appropriate experiments. Hardness was found to be maximum for the composite containing 3% of seashell powder. Tribological behaviour of the composites were optimized using response surface methodology. Wear and frictional resistance of the composites increased with the content of seashell powders and it was the most influential factor according to optimization results. Surface morphology was examined through scanning electron microscopic technique to know the influence of seashell powder on the wear behaviour of the composites and the type of wear occurred.

Recent advances in nanocellulose-based different biomaterials: types, properties, and emerging applications

The research interest in sustainable and eco-friendly materials based on natural sources has increased dramatically due to their recyclability, biodegradability, compatibility, and nontoxic behavior. Nanocellulose contains chains of glucose residue and is an abundantly available green material. Recently, nanocellulose-based green composites are under extensive exploration and gained popularity among researchers owing to their lightweight, lost cost, low density, excellent mechanical and physical characteristics. These materials have also shown tremendous potential for applications in biomedical and numerous engineering fields. The mechanical properties of these materials play a vital role in effective utilization and their exploration for future applications. This review article comprehensively presents current developments, results, and findings in the arena of green and sustainable materials. Currently, the main problem is the large variability in their properties and qualities. Nanocellulose properties are influenced by various factors, including the fiber type, ecological conditions, manufacturing methods, and any alteration of the fiber surface. Finally, the review incorporates future challenges and opportunities in the field of nano cellulosic materials.

Coupled resonance via localized surface plasmon polaritons in Iridium-based refractory metamaterials

Plasmonic metamaterials (MMs) have enabled their novel applications across numerous engineering fields ranging from photodetecting to bio-imaging, cancer diagnosis, and photovoltaics. However, as a vast majority of reported plasmonic MMs are based on materials with a relatively low melting point such as Au or Ag, their utilities are limited for lower-temperature applications. Thus, realizing plasmonic resonance based on refractory materials will further extend their applications to higher-temperature environments. In this work, we numerically report plasmonic MMs built with Ir and HfO2, which are well-known highly refractory materials. These plasmonic MMs resonate selectively based on the excitation of localized surface plasmon polaritons and magnetic resonances. The wavelength where resonance occurs can be modulated by changing the width of the top metal of the structure. Moreover, we find that the resonance wavelength and the top metal’s width are in a polynomial relationship over the wavelength range studied. Therefore, with the tunable properties, the refractory plasmonic MMs in this work present a potential to extend the utilities of plasmonic devices for higher-temperature applications.

The analysis on electrical conductivity of AA6061/rice husk ash composites

Metal matrix composites are demanded broadly in numerous fields of engineering and industrial sectors . In the current study, the effects of rice husk ash on AA6061 was considered by altering RHA at 2%, 4%, 6% and 8% by weight at a stirring speed of 300 rpm. In the present situation, a pattern of aluminium alloy strengthened with RHA particles fabricated by stir casting method at 600 °C and 750 °C pouring temperatures are formed and analysed. Microstructural analysis was carried out for aluminium alloy and aluminium/RHA composites using an optical microscope. The research shows that as the percentage of reinforcement increases, there is an increase in crystallite size and micrographs results indicate the presence of silica from rice husk ash on aluminium alloy. From the electrical properties examination, The RHA reinforcement increased the conductance of the AA6061 metal matrix thereby, increasing the capacity of the metal matrix to conduct electricity because of the presence of RHA in the developed composites.

Investigation of cutting mechanisms in the machining of Ceramic Matrix Composites (CMCs)

Ceramic Matrix Composites (CMCs) are increasingly used in numerous engineering fields, e.g. the aerospace, automotive, energy & nuclear industry due to their higher permissible material temperature and their lower weight compared to metallic materials. Thanks to the quasi-ductile material behaviour, it is possible to carry out time- and cost-efficient finishing with a geometrically defined cutting edge.In this study the cutting mechanisms are analysed in fundamental cutting tests on an orthogonal cutting test bench by variance of the undeformed chip thickness. For the evaluation cutting force measurements, high-speed recordings, surface qualities measurements and chip analyses were conducted.

The Effects of Internal Heat Generation or Absorption on Mixed Convection in a Lid-Driven Rectangular Cavity using Finite Volume Method

Mixed convection heat transfer in cavities is a significant phenomenon in numerous engineering fields, such as nuclear reactors, solar energy storage, and heat exchangers. Despite acknowledging that a square is a basic shape found in these systems, not all the figures are geometrical. Less attention was given to the rectangle cavity even though it could be found in these systems. Various internal reactions could occur inside the systems, especially in geothermal heat exchangers. Therefore, this research aims to analyze the effect of internal heat generation or absorption in a two-dimensional (2D) horizontal cavity to the fluid flow and heat transfer process numerically. The vertical walls are well insulated. Meanwhile, the top and bottom walls are kept at and , respectively, where . The top wall moves at a constant speed from left to right. The finite volume method (FEM) and SIMPLE algorithm are employed to discretize the governing equations. Next, the algebraic equations are solved iteratively using the tri-diagonal matrix algorithm (TDMA). The influences of heat generation or absorption parameters are investigated in terms of the flow, heat transfer, and Nusselt number. The numerical results are plotted in the form of streamlines and isotherms. It is found that the presence of heat generation or absorption has a significant effect on the fluid flow and heat transfer process in the horizontal cavity. Overall, for internal heat generation, the heat transfer rate decreases, while the opposite pattern can be observed for the case of internal heat absorption. However, for Ri = 10.0, as the heat generation's value increases from 2 to 4, the heat transfer rate is the same.