Laminar Fluid Flow Research Articles

Symmetrisation of Laminar Flow of Viscous fluid in a Flat Diffuser by Periodic Influence on the Inlet Flow Velocity

The technique for symmetrisation of an asymmetric flow of a viscous incompressible fluid in a flat diffuser by means of a weak periodic vibration effect on the inlet flow is shown in the paper. The results are obtained for a viscous in-compressible fluid by modelling based on the numerical solution of the Navier-Stokes equations.

Dinamik Mikroakışkan Hücre Kültürü Platformlarında Difüzyon-Konveksiyon Proseslerinin Hesaplamalı Akışkanlar Dinamiği Modellemesi

Mikroakışkan tabanlı biyokimyasal analizler, hücre ve doku mühendisliğindeki son gelişmeler, mikroakışkan sistemler içinde uzaysal-zamansal olarak kütle transferinin kontrol edilmesine dayanmaktadır. Mikroakışkan sistemler ile hücresel mikroçevrenin kontrol edilmesi ve doku benzeri yapıların taklit edilmesinin yanısıra, yüksek verimli analizlerin gerçekleştirilmesinde de oldukça kullanışlı araçlardır. Bu sistemler biyoaktif moleküllerin, nütrientlerin, büyüme faktörlerinin ve diğer hücresel regülatör moleküllerin konsantrasyon gradientlerinin zamana ve konuma bağlı olarak kontrol etme potansiyeline sahiptir. Bu nedenle mikrosistemlerde biyomoleküllerin taşınım olaylarının modellenmesi, mikroakışkan platformların tasarımını ve kantitatif biyolojik analizleri kolaylaştıran değerli ve kullanışlı bir analitik araçtır. Geliştirilen analitik model mikroakışkan sistem tasarımına rehberlik ettiğinden; maliyetli ve zaman alıcı deneyler minimuma indirilebilmekte; tasarım süreci verimliliği ve etkinliği arttırılabilmektedir. Çalışma kapsamında ilaç taşınım uygulamalarına yönelik tek kanallı mikroakışkan platformda biyomoleküllerin difüzyon ve konveksiyon proseslerine vurgu yaparak kütle transferi profilini gösteren analitik bir model oluşturulmuştur. Mikroakışkan hücre kültürü sistemlerinin hücresel fizyolojik ortamların akış dinamiğini taklit edebilmesi için pulsatil laminar sıvı akışını sağlayabilen peristaltik pompa ile sistem kurulmuştur. Dinamik akış koşulları altında hücreler üzerine etki eden biyomekanik kuvvetlerin (akış hızı, konsantrasyon, basınç dağılımı ve kayma gerilimi) etkisini sayısal olarak incelemek için COMSOL Multiphysics sonlu elemanlar yazılımı kullanılarak mikroakışkan sistemin sayısal simülasyonu yapılmıştır. Mikroakışkan sistemde hücreler minimum kayma gerilimine maruz bırakılırken, kanal uzunluğu boyunca konsantrasyon profilinin korunduğu gösterilmiştir. Akış hızının arttırılmasıyla mikro kanal boyunca çözünen konsantrasyon dağılımı değiştirilebilmektedir ve bu da hücreler üzerindeki kayma gerilimini arttırmaktadır. Simülasyonu yapılan mikroakışkan analitik modelin, hücre kültürü, biyolojik analizler ve ilaç taşıyıcı sistemler için kullanılacak mikroakışkan platformların geliştirilmesinde sistem tasarımı ve parametre seçimi için temel olarak kullanılabileceği düşünülmüştür.

Analysis of second grade hybrid nanofluid flow over a stretching flat plate in the presence of activation energy

The research of fluid containing nanoparticles for the heat transport characteristics is very famous because of its variety of real-life applications in various thermal systems. Although the thermal efficiency of the nanofluid was effective but still the nano scientists were trying to introduce some new advance class of fluid. Therefore, an advance class of fluid is developed by the dispersion of two different nano sized particles in the conventional base fluid known as “Hybrid nanofluid” which is more effective compared to simple nanofluids in many engineering and industrial applications. Therefore, motivated from the hybrid type of nanofluids in the current research we have taken two-dimensional laminar and steady flow of second grade fluid passing through porous plate. The engine oil base fluid is widely used fluid in the engineering and industrial problems. Keeping these applications in mind the engine oil is considered and two different nanoparticles Copper and aluminum oxide are added in ordered to get the required thermal characteristics. In addition to this the thermal radiation, chemical reaction, activation energy, Brownian motion and thermophoresis are also addressed during the current research. The present proposed higher-order PDE’s is transformed to the non-linear system of ODE’s. For the solution of the proposed high non-linear model HAM method is employed. As the hybrid nanofluid are highlighted on the second-grade fluid flow over a horizontal porous flat plate. During the present analysis and experimental study, it has been proved that the performance of hybrid nanofluid is efficient in many situations compared to nanofluid and regular fluid. For physical interpretation all the flow parameters are discussed through graphs. The impact of volume fraction is also addressed through graphs. Moreover, the comparative analysis between hybrid and nanofluid is carried out and found that hybrid nanofluid performed well as compared to nanofluid and regular fluid. The engineering quantities obtained from the present research have been presented in tables.

An Approximate Method for Predicting the Friction Factor of Viscoplastic Shear-Thinning Fluids in Non-Circular Channels of Regular Cross-Sections.

The objective of this study is to provide a straightforward generalized simple and quick method for the prediction of the friction factor for fully developed laminar flow of viscoplastic shear-thinning fluids in non-circular channels of regular cross-sections. The most frequently represented substances processed under these conditions are polymers in the processing and plastics industry. A generalized approximate method was proposed to express the relationship between the friction factor and the Reynolds number for the Herschel-Bulkley rheological model. This method uses the generalized Reynolds number for power-law fluids. Moreover, an additional simplified method for rapid engineering calculations was obtained as well. The suggested method was verified by comparing experimental data for concentric annulus found in the literature and results from simulations for concentric annulus, rectangular, square duct with a central cylindrical core and elliptical cross-sections. The results showed that the suggested methods enable us to estimate the friction factor with high accuracy for the investigated geometries.

Entropy generation and characteristics of mixed convection in lid-driven trapezoidal tilted enclosure filled with nanofluid

The investigation of steady, incompressible, laminar mixed convective fluid flow within two different types of tilted lid-driven trapezoidal enclosures filled with nanofluid composed of water and Al2O3 nanoparticles has been carried out in this paper. The upper wall of the enclosure is an isothermal cold surface that travels at a constant speed, while the bottom surface of the cavity maintains a constant high temperature. Non-dimensional governing equations along with the appropriate boundary conditions are solved using Galerkin finite element technique. Parametric simulation has been conducted by varying tilt angle of the base wall from 0° to 45°, Reynolds number from 0.1 to 103, Grashof number from 10−2 to 106, and Richardson number between 0.1 and 10 for three different cases. The streamlines and the isotherms are used to describe the fluid flow and heat transfer characteristics within the enclosure. Besides, the quantitative evaluations of thermal enhancement in terms of the average Nusselt number, average fluid temperature, and Bejan number of the enclosure are presented. Effects of base wall tilt angle and the presence of nanofluid on convection heat transmission characteristics as well as Bejan number are also explored.

Viscometer for investigating the viscosity of magnetic fluid media

The rational application of magnetic fluids in various technical systems requires their stability analysis, hydrodynamic particle size, dissipative processes in the colloid control. The existing viscometers do not fully meet all requirements, in particular, they do not allow research in a magnetic field of given magnitude and certain topography. It is proposed to determine rheological properties of magnetic fluids using rotary viscometer, in which two measuring gaps are structurally designed and filled with studied fluid, which is important for calculating characteristics of low viscosity magnetic media. The device design implements practically homogeneous magnetic field, varying within wide range and directed perpendicular to liquid shear stress. The device allows to steadily maintain shear rate in medium under study, and to determine viscosity with a sufficiently large change. A small magnetic fluid volume is required to estimate rheological characteristics. The accuracy of measurements of the internal friction force, device heating temperature, coaxial cylinders rotation speed and magnetic field inside investigated medium meet the requirements of international standards. Laminar fluid flow process in the device gap is described mathematically. This made it possible to justify the construction geometrical dimensions in order to increase the measurements and determine rheological properties of low-viscosity magnetic materials. The formulas for calculation of Newtonian fluid viscosity coefficient, shear stress and shear rate based on experimental data were obtained.

Heat transfer analysis in cylindrical polar system with magnetic field: A novel Hybrid Analytical and Numerical Technique

This article uses a new semi-analytical technique to solve the heat and mass transfer problem. The problem is a viscous, incompressible, laminar axisymmetric flow of a micropolar fluid with presence of magnetic field is considered between two stretchable disks. The governing parameters of the problem can be described better when similarity transformation is utilized to convert a set of nonlinear PDEs into a nonlinear system of ordinary differential equations (ODEs). The effect of different parameters such as radiation parameter, magnetic field, Eckert number, Reynolds number, Schmidt number, and Prandtl number on the profiles of microrotation, velocity, concentration, and temperature are shown with the corresponding graphs. To investigate the validity of this method, the obtained figures have been compared with the graphs that obtained from the numerical method of Runge Kutta and the semi-analytical techniques of the homotopy perturbation method (HPM) that was published earlier. The average error between HAN method and HPM method, for radial velocity is 3.1%, for axial velocity is 0.69%. The comparisons show that the method has high accuracy and efficiency and can be used in many engineering and thermal problems that have nonlinear differential equations.

Applicable Investigation of SPH in Characterization of Fluid Flow in Uniform and Non-Uniform Periodic Porous Media

Today, the use of numerical modeling for characterizing properties of porous media and related concepts has been widely extended, especially in subsurface flow issues such as geological CO2 storage and petroleum recovery. Therefore, in this study, the fundamental problem of laminar fluid flow through uniform or non-uniform and periodic array of cylinders was functionally investigated using the smoothed particle hydrodynamics (SPH) method as a modern and applied method of modeling in order to develop the past studies and introduce a complementary numerical tool alongside laboratory methods. All modeling processes were performed in the form of dimensionless processes for generalization and applicability at different scales. The results were used to characterize properties of porous media and to investigate basic properties such as fluid velocity, permeability, streamlines, and hydraulic tortuosity. Accuracy of modeling was shown in comparison with the results obtained in the literature. In this study, the potential of the method has been investigated in order to show the ability in modeling characteristic laboratory experiments of porous media and the possibility of using it instead of them. For this purpose, three periodic models of uniform and randomly distributed non-uniform porous media with arrays of circular, square, and diamond-shaped cylinders in a porosity range of 30–95%, with different types of cylinder distribution at the pore scale, were investigated. New equations were proposed for permeability as a function of porosity. Moreover, the method of tortuosity calculation was investigated directly through the time history of properties in the SPH method, and shape factors were obtained for the studied porous media models. The results showed that the geometry of a square cylinder with distribution in a square grid led to a higher permeability than circular and diamond-shaped grids. In contrast, diamond-shaped geometry with distribution in a hexagonal grid led to higher permeability than the other two models. Furthermore, diamond-shaped geometry had higher tortuosity, and circular and square geometries had almost identical tortuosity. Increasing the size of the modeling domain and decreasing the size of cylinders (i.e., decreasing resolution) reduces effects of the shape and the geometry of cylinders and achieves the same results. Random and non-uniform distribution of cylinders within porous media reduces fluid velocity, permeability, tortuosity, and shape factor (p) compared to the uniform models.

Analytical investigation of an incompressible viscous laminar Casson fluid flow past a stretching/shrinking sheet

This paper presents an analytical approach on capturing the effect of incompressible, non-Newtonian, viscous, Casson nanofluid flow past a stretching/shrinking surface, under the influence of heat radiation and mass transfer parameter. The governing nonlinear partial differential equations are first transformed into a series of associated nonlinear ordinary differential equations with aid of predictable transformation, while numerical computations follow. The implied nanofluid here is aluminum oxide (Al_{2} O_{3}). The analytical solution is exploited to reveal the accompanying non-dimensional boundary value problem and output results are employed to verify the method's reliability, where it is shown that they agree with current findings in the field. An incomplete gamma function is used to solve temperature equation analytically. We present various instances of the solution, depicting effects of the essential flow factor, the stretching/shrinking parameter, the mass transfer parameter, radiation parameter, and Prandtl number.

Gaseous slip flow in a porous two-dimensional rectangular microchannel subjected to inclined magnetic field

In this study, two-dimensional, steady, laminar, and compressible gaseous flow of Newtonian fluid in a rectangular porous microchannel affected by an electromagnetic field, and under local thermal equilibrium condition was analytically investigated in the slip flow region (0.001<Kn < 0.1). The porous microchannel is entirely affected by uniform inclined magnetic field with an angle α from the positive x-axis, the range of this angle is 0 ≤ α ≤ 90°. Also, the porous microchannel effected by uniform electric field which points in the positive z-direction. Thermophysical properties of the fluid were assumed to be constant. The normalized governing equations were asymptotically solved and expressions of the flow velocity components, the pressure, and the temperature were provided using first-order velocity slip and temperature jump boundary conditions. The effects of various parameters on the flow were studied, such as Darcy number, the porosity, the thermal conductivity ratio, the electrical conductivity ratio, Hartmann number, Knudsen number, the electric field to magnetic field ratio (0 ≤ K ≤ 1), and the magnetic field inclination angle. It was found that increasing the permeability of the porous medium increases the flow velocity but decreases its temperature. Further, the results reveal that applying a stronger magnetic field in absence of electric field decreases the flow velocity but increases its temperature. On the other hand, the stronger the electric field, the higher the flow velocity and its temperature. Also, as the magnetic field inclination angle increases the flow velocity decreases. The effects of Darcy number and the electrical conductivity ratio on the heat flux were studied as well. A comparison of the analytical solutions with the numerical results were presented as a validation for this study. The comparison showed that the analytical results were in good agreement with the numerical results.

Numerical investigation of heat transfer enhancement in microchannel heat sink with fan cavities using secondary channels and ribs

A computational three-dimensional modeling of microchannel heat sink (MCHS) with fan cavity and four different rib configurations along with secondary channels (SCs) has been performed in detail to identify the influence of geometrical parameters on characteristics of heat transfer and provide insight into optimum configuration. The adverse effect of high processing speed and heat flux demands lower operational temperature at the expense of high pumping power in order to increase the lifespan of electronic equipment. Single phase, laminar flow of fluid is considered in the Reynolds number range from 136 to 588. The novel design of the SC benefits heat transfer enhancement by the increase in flow area, originates secondary flows subsequently transforms into symmetric counter-rotating vortices on the basis of rib, however, the influence of the rib blocking effect also depletes, resulting in minimal pressure drop. The comparison between various rib structures confirms that the FC-FTR-SC configuration acquired superior heat transfer performance with a TP of 2.07, at Re = 261. The FC-FTR-SC configuration has a great deal of evidence that pumping power decreases by 10.1% and TP increases by 11.7% as β increases from 0.5 to 1.25. The influence of four geometric parameters: relative width of rib ( α), relative width of the SC ( β), relative length of cavity ( γ), and relative angle of the SC ( ϕ) on heat transfer enhancement and pressure drop have been performed using parametric optimization, response surface methodology.

Stepwise mathematical derivation of the Herschel–Bulkley laminar fluid flow equations—in pipes

Stepwise derivation of flow equations of the Herschel–Bulkley (HB) model is not available in the literature. These equations are crucial for mechanical, chemical and petroleum engineering academia and industries where fundamental works on non-Newtonian fluids may be done to reach future models and estimation methods. Therefore, this work focuses on derivation of laminar flow equations and estimation methods of HB fluids through pipes. In this work, first, stepwise derivation of the HB fluid flow parameters consisting of fluid velocity, flow rate, average velocity and relative velocity equations is presented, followed by a straightforward mathematical model for use in numerical solution. Next, stepwise mathematical derivation of the laminar pressure drop equations by Merlo et al. (An innovative model for drilling fluid hydraulics. Paper presented at the SPE Asia Pacific oil and gas conference, Kuala Lumpur, Malaysia, 1995) and Gjerstad and Time (SPE J 20:1–18, 2014) is presented, and finally practical and user-friendly calculation procedures for different estimation methods are presented. The step-by-step derivation procedures presented in this work contribute to effective learning for engineering students and practitioners in addition to providing a clear example derivation guideline for future researchers to reach other more accurate non-Newtonian hydraulics models and estimation methods.

Laminar Viscous Fluid Flow with Micro-rotation Capabilities through Cylindrical Surface

Viscous fluid can micro-rotate due to collisions between particles that affect viscous fluid's velocity and temperature.This study aims to determine the effect of viscosity parameters, micro-rotation materials, and heat sources on fluid velocity and temperature. The model of the laminar flow equation for viscous fluid in this study uses the laws of physics, namely, the law of conservation of mass, Newton II, and Thermodynamics I. The formed dimensional equations are converted into non-dimensional equations by using non-dimensional variables. Then, the non-dimensional equations are converted into similarity equations using stream function and similarity variables. The formed similarity equation was solved numerically by using the Gauss-Seidel method. The results of this study indicate that the velocity and temperature of the viscous fluid flow can be influenced by the parameters of viscosity, micro-rotation material, and heat source. The presence of collisions between particles causes heat to cause an increase in the variance of viscosity parameters, micro-rotation materials, and heat sources. Therefore, the viscous fluid's velocity decreases and its temperature increases.

Subdomain method for unsteady flow of ZnO − SAE50 nano-lubricant through expanding/contracting walls in an asymmetric porous horizontal channel

The laminar time-dependent fluid flow of an engine oil (Zinc Oxide−Society of Automotive Engineers 50 alias ZnO − SAE50 nano-lubricant) through a rectangular channel is presented. The channel is made up of permeable walls that can expand or contract. It is also under the impact of thermal radiation and magnetic field is dominant enough to be ignored. The lower and upper walls of the channel bear different permeabilities and temperatures. Hence, a system of governing nonlinear partial differential equations is setup by means of conversation laws and aforementioned assumptions. By the implementation of suitable similarity transformations and conservation of mass, the equations for momentum, and energy are reduced to relatively simpler system of ordinary differential equations. The resulting system is solved by employing a semi analytical technique named as Subdomain Method (SDM). The results are further supported by another numerical scheme (a duos of shooting method along with Runge-Kutta-Fehlberg algorithm). The functioning of flow and temperature profiles under the variation in significant physical parameters is demonstrate upon the description of graphs and tables. Thorough discussions and concluding results are also presented at the end of the manuscript.

Drag reduction and the Vogel exponent of a flexible beam in transient shear flows

Interactions between a flexible beam and a fluid in a channel are of great relevance to biological hairy surfaces, aquatic vegetation, marine life (e.g., fish gills), and many industrial systems alike. While steady state response of a beam to such flows is fairly well-explored, their behavior in the transient regime is not fully understood. A series of numerical simulations are performed to study the laminar Couette flow of an incompressible viscous fluid past an elastic beam in a two-dimensional channel. The flexible beam is perpendicular to the direction of flow, and its base is fixed to the stationary bottom of the channel. We measure the evolution of the Vogel exponent, drag reduction, and reconfiguration number during the transient and steady-state response of the fluid–structure system for different geometrical and physical properties. Our benchmark shows a good agreement between numerical and experimental observations. Our results show that the system's steady-state response at different bulk-fluid velocities can be reproduced by investigating the shear flow response during the transient regime. We define a new variable that characterizes the evolution of the local velocity profile in the proximity of the free end of the beam and use that to characterize the transient-regime response. The analysis yields insight into the competing effects of elasticity of the beam and non-linear flow response.

Mixed electroosmotic/pressure-driven flow for a generalized Phan–Thien–Tanner fluid in a microchannel with nonlinear Navier slip at the wall

This work derives an approximate solution of the laminar viscoelastic fluid flow through a parallel flat plate microchannel, driven by electroosmotic and external pressure forces. In contrast to other works published in the past, in the present analysis, the fluid’s rheology obeys the generalized Phan–Thien–Tanner model that has been proposed recently, which uses the Mittag-Leffler function instead of linear or exponential functions of the trace for the stress tensor. The hydrodynamic analysis considers a non-linear Navier slip law at the wall that follows a power-law behavior on the shear stress. For the electric potential in the electric double layer, the Debye–Hückel approximation was used, and it is assumed that the wall’s zeta potentials are symmetric. The solution obtained in this work depends on several dimensionless parameters that allow controlling the flow: ɛWi2 characterizes the fluid’s viscoelasticity, the electrokinetic parameter κ̄, the dimensionless slip coefficient L̄, the slip-power exponent m, and the ratio between pressure and electroosmotic forces, G. Besides, the influence of two parameters of the Mittag-Leffler function, α and β, notably affects the flow’s characteristics. Our results evidence the important consequences of considering the generalized Phan–Thien–Tanner model and the slippage effect on the flow field compared to that described by the Phan–Thien–Tanner model.

Effect of fluid velocity and particle size on the hydrodynamic diffusion layer thickness

The aim of this study was to determine the thickness of the hydrodynamic diffusion layer (hHDL) of three poor water-soluble compounds under laminar fluid flow using a single particle dissolution technique. The single particle dissolution experiments were performed in a flowing aqueous medium using four different fluid velocities (v), ranging from 46 to 103 mm/s. The particles used had an initial radius (r) of 18.8 to 52.3 μm. The determined hHDL values were calculated from both dissolution experiments and computational fluid dynamics (CFD) simulation. In this study, single particle dissolution experiments gave, with one exception, hHDL values in the range of 2.09 to 8.85 µm and corresponding simulations gave hHDL values in the range of 2.53 to 4.38 µm. Hence, we found a semi-quantitative concordance between experimental and simulated determined hHDL values. Also, a theoretical relation between the dependence of hHDL on particle radius and flow velocity of the medium was established by a series of CFD simulations in a fluid velocity range of 10–100 mm/s and particle size (radius) range of 5–40 µm. The outcome suggests a power law relation of the form hHDL∝r3/5v-2/5. In addition, the hHDL seems to be independent of the solubility, while it has a diffusion coefficient dependence. In conclusion, the hHDL values were determined under well-defined conditions; hence, this approach can be used to estimate the hHDL under different conditions to increase the understanding of the mass transfer mechanisms during the dissolution process.

Kinematic Properties of a Twisted Double Planetary Chaotic Mixer: A Three-Dimensional Numerical Investigation.

In this study, a numerical investigation based on the CFD method is carried out to study the unsteady laminar flow of Newtonian fluid with a high viscosity in a three-dimensional simulation of a twisted double planetary mixer, which is composed of two agitating rods inside a moving tank. The considered stirring protocol is a “Continuous sine squared motion” by using the dynamic mesh model and user-defined functions (UDFs)to define the velocity profiles. The chaotic advection is obtained in our active mixers by the temporal modulation of rotational velocities of the moving walls in order to enhance the mixing of the fluid for a low Reynolds number and a high Peclet number. For this goal, we applied the Poincaré section and Lyapunov exponent as reliable mathematic tools for checking mixing quality by tracking a number of massless particles inside the fluid domain. Additionally, we investigated the development of fluid kinematics proprieties, such as vorticity, helicity, strain rate and elongation rate, at various time periods in order to view the impact of temporal modulation on the flow properties. The results of the mentioned simulation showed that it is possible to obtain a chaotic advection after a relatively short time, which can deeply enhance mixing fluid efficiency.

Hydraulic properties of capillary mats used for low-energy cooling and heating of buildings

The article deals with the hydraulic behaviour of capillary mats most often used for high-temperature cooling or low-temperature heating of buildings. On the basis of experimental measurements, the dependences of the pressure loss of the capillary mats on the water flow rate in relation to their geometrical arrangement were obtained. The measured values were compared with the manufacturer's data and it was found that the measured values differ significantly. The CFD simulation method was used to model the pressure losses of the capillary mats. The main emphasis was placed on the friction losses in the capillary during laminar fluid flow and local losses during the branching and coupling of the flows for the changing flow regime. Based on the simulation calculations, the dependences of the local loss coefficient during the flow diverging and converging and the relationship for the calculation of the coefficient of friction in the unsteady region of laminar flow were obtained. Based on the obtained results, an analytical computational model was built to determine the pressure losses of the capillary mats based on an iterative and approximate solution. The example shows the differences between the different approaches to the solution. The results of the presented model are compared with the experimentally obtained data. The article presents the share of partial components in the total pressure loss of the mats.

Numerical study on the inhomogeneity of the contact layer between solid oxide electrolysis cell anode and the interconnect

AbstractAlthough the anode‐side contact layer plays a vital role in the performance improvement of solid oxide electrolysis cell (SOEC) stacks, it is hard to prevent defect formation in the process of cell manufacture. Due to the difficulty of in situ observation, in this study, a 2D SOEC model was built to investigate the defects' impacts on the cell regarding laminar fluid flow, steady‐state heat transfer, and electrochemistry. The finite element method was employed to solve the governing equations. The parameters in the calculating field in terms of gas velocity, current density, and temperature were evaluated to identify the impacts of the defects on the contact layer. This evaluation showed that numerically computed temperatures around the defects substantially differ from the main cell, which can lead to stress maldistribution and ultimately result in the delamination between the contact layer and anode.